USB-5203
Multi-sensor Measurement and Data Logger

User's Guide

Document Revision 14A
January 2015
© Copyright 2015

Trademark and Copyright Information
Measurement Computing Corporation, InstaCal, Universal Library, and the Measurement Computing logo areeither trademarks or registered trademarks of Measurement Computing Corporation. Refer to the Copyrights &Trademarks section on mccdaq.com/legal for more information about Measurement Computing trademarks.
Other product and company names mentioned herein are trademarks or trade names of their respective
companies.
© 2015 Measurement Computing Corporation. All rights reserved. No part of this publication may be
reproduced, stored in a retrieval system, or transmitted, in any form by any means, electronic, mechanical, by
photocopying, recording, or otherwise without the prior written permission of Measurement Computing
Corporation.
NoticeMeasurement Computing Corporation does not authorize any Measurement Computing Corporation product for
use in life support systems and/or devices without prior written consent from Measurement Computing
Corporation. Life support devices/systems are devices or systems that, a) are intended for surgical implantation
into the body, or b) support or sustain life and whose failure to perform can be reasonably expected to result ininjury. Measurement Computing Corporation products are not designed with the components required, and are
not subject to the testing required to ensure a level of reliability suitable for the treatment and diagnosis ofpeople.

HM USB-5203

2

Table of Contents
Preface

About this User’s Guide ....................................................................................................................... 5
What you will learn from this user's guide ......................................................................................................... 5
Conventions in this user's guide ......................................................................................................................... 5
Where to find more information ......................................................................................................................... 5
Chapter 1

Introducing the USB-5203 .................................................................................................................... 6
Logging data with the USB-5203 ..................................................................................................................................... 6

Functional block diagram ................................................................................................................................... 7
Chapter 2

Installing the USB-5203 ........................................................................................................................ 8
Unpacking........................................................................................................................................................... 8
Installing the software ........................................................................................................................................ 8
Installing the hardware ....................................................................................................................................... 8
Firmware revision 2.12 and earlier ................................................................................................................................... 8
Firmware revision 3.0 and later ........................................................................................................................................ 8

Configuring the hardware ................................................................................................................................... 9
Configuring data logging options...................................................................................................................................... 9

Calibrating the hardware..................................................................................................................................... 9
Factory calibration ............................................................................................................................................................ 9
Field-calibration ................................................................................................................................................................ 9
Chapter 3

Sensor Connections ........................................................................................................................... 10
Screw terminal pin out ...................................................................................................................................... 10
Sensor input terminals (C0H/C0L to C7H/C7L) ..............................................................................................................10
Current excitation output terminals (±I1 to ±I4) ..............................................................................................................11
Four-wire, two sensor common terminals (4W01 to 4W67) ............................................................................................11
Two sensor common terminals (IC01 to IC67) ................................................................................................................11
Digital terminals (DIO0 to DIO7) ....................................................................................................................................11
CJC sensors......................................................................................................................................................................11
Power terminals (+5V).....................................................................................................................................................11
Ground terminals (GND) .................................................................................................................................................11

Thermocouple connections ............................................................................................................................... 11
Wiring configuration........................................................................................................................................................12

RTD and thermistor connections ...................................................................................................................... 12
Two-wire configuration ...................................................................................................................................................13
Three-wire configuration .................................................................................................................................................14
Four-wire configuration ...................................................................................................................................................14

Semiconductor sensor measurements ............................................................................................................... 15
Wiring configuration........................................................................................................................................................15

Digital I/O connections ..................................................................................................................................... 16
Configuring the DIO channels to generate alarms ...........................................................................................................16
Chapter 4

Functional Details ............................................................................................................................... 17
Thermocouple measurements ........................................................................................................................... 17
Cold junction compensation (CJC) ..................................................................................................................................17
Data linearization .............................................................................................................................................................17
Open-thermocouple detection (OTD) ..............................................................................................................................17

RTD and thermistor measurements .................................................................................................................. 18
Data linearization .............................................................................................................................................................18

External components ........................................................................................................................................ 183

USB-5203 User's Guide

Screw terminals................................................................................................................................................................18
USB connector .................................................................................................................................................................19
LED .................................................................................................................................................................................19
CompactFlash® memory card slot....................................................................................................................................19
Data logging button .........................................................................................................................................................20

External power supply ...................................................................................................................................... 21
Disconnecting the USB-5203 from the computer ............................................................................................. 21
Transferring binary data after a logging session ............................................................................................... 21
Converting binary data after a logging session ................................................................................................. 21
Chapter 5

Specifications ...................................................................................................................................... 22
Analog input ..................................................................................................................................................... 22
Channel configurations ..................................................................................................................................... 22
Compatible sensors ........................................................................................................................................... 23
Accuracy ........................................................................................................................................................... 23
Thermocouple measurement accuracy .............................................................................................................................23
Semiconductor sensor measurement accuracy .................................................................................................................24
RTD measurement accuracy ............................................................................................................................................24
Thermistor measurement accuracy ..................................................................................................................................25

Throughput rate to PC ...................................................................................................................................... 25
Digital input/output........................................................................................................................................... 26
Temperature alarms .......................................................................................................................................... 27
Memory ............................................................................................................................................................ 27
Microcontroller ................................................................................................................................................. 27
Data Logging .................................................................................................................................................... 28
Real time clock ................................................................................................................................................. 28
USB +5V voltage ............................................................................................................................................. 29
Power ................................................................................................................................................................ 29
USB specifications ........................................................................................................................................... 29
Current excitation outputs (Ix+) ....................................................................................................................... 30
Environmental .................................................................................................................................................. 30
Mechanical ....................................................................................................................................................... 30
Screw terminal connector ................................................................................................................................. 30
Declaration of Conformity .................................................................................................................. 32

4

Preface

About this User’s Guide
What you will learn from this user's guideThis user's guide describes the Measurement Computing USB-5203 data acquisition device and lists device
specifications.

Conventions in this user's guide
For more information
Text presented in a box signifies additional information related to the subject matter.
Caution! Shaded caution statements present information to help you avoid injuring yourself and others,
damaging your hardware, or losing your data.
bold text

Bold text is used for the names of objects on a screen, such as buttons, text boxes, and check boxes.

italic text

Italic text is used for the names of manuals and help topic titles, and to emphasize a word or phrase.

Where to find more information
Additional information about USB-5203 hardware is available on our website at www.mccdaq.com. You canalso contact Measurement Computing Corporation with specific questions.


Knowledgebase: kb.mccdaq.com
Tech support form: www.mccdaq.com/support/support_form.aspx
Email: techsupport@mccdaq.com
Phone: 508-946-5100 and follow the instructions for reaching Tech Support

For international customers, contact your local distributor. Refer to the International Distributors section on our
website at www.mccdaq.com/International.

5Chapter 1

Introducing the USB-5203
The USB-5203 provides eight differential input channels that are software-programmable for different sensor
categories including thermocouple, RTDs, thermistors, and semiconductor sensors.
Eight independent, TTL-compatible digital I/O channels are provided to monitor TTL-level inputs,
communicate with external devices, and to generate alarms. The digital I/O channels are softwareprogrammable for input or output.
With the USB-5203, you can take measurements from four sensor categories:

Thermocouple – types J, K, R, S, T, N, E, and B
Resistance temperature detectors (RTDs) – 2, 3, or 4-wire measurements of 100 Ω platinum RTDs
Thermistors – 2, 3, or 4-wire measurements
Semiconductor temperature sensors – LM36 or equivalent

The USB-5203 provides a 24-bit analog-to-digital (A/D) converter for each pair of differential analog input
channels. Each pair of differential inputs constitutes a channel pair.
You can connect a different category of sensor to each channel pair, but you cannot mix categories among thechannels that constitute a channel pair (although it is permissible to mix thermocouple types).
The USB-5203 provides two integrated cold junction compensation (CJC) sensors for thermocouple
measurements, and built-in current excitation sources for resistive sensor measurements.
An open thermocouple detection feature lets you detect a broken thermocouple. An on-board microprocessor
automatically linearizes the measurement data according to the sensor category.
The USB-5203 features eight independent temperature alarms. Each alarm controls an associated digital I/O
channel as an alarm output. The input to each alarm is one of the temperature input channels. The output of each
alarm is software configurable as active high or low. You set up the temperature threshold conditions to activate
each alarm. When an alarm is activated, the associated DIO channel is driven to the output state.
You can log your sensor measurements to a CompactFlash® memory card. CompactFlash is a removable nonvolatile storage device. A 512 MB CompactFlash memory card is shipped with the device to store your data.
For more information, refer to Logging data with the USB-5203 below.
The USB-5203 device is compatible with both USB 1.1 and USB 2.0 ports. The speed of the device may belimited when using a USB 1.1 port due to the difference in transfer rates on the USB 1.1 versions of the
protocol (low-speed and full-speed).
External power is required for data logging operations
Due to processing limitations, you cannot log data to the memory card when the USB-5203 is connected to yourcomputer's active USB bus. When operating as a data logger, disconnect the USB cable from the computer, andconnect the external power supply shipped with the device.
The USB-5203 is a standalone plug-and-play device. External power is required for data logging mode only. All
configurable options are software programmable. The USB-5203 is fully software calibrated.

Logging data with the USB-5203
Due to processing limitations, you cannot log data to the memory card when the USB-5203 is connected to an
active USB port. When operating as a data logger, disconnect the USB cable from the computer, and connect
the external power supply shipped with the device.
The USB-5203 has many software-selectable options for setting up data logging.
You can record:

temperature (° C) or raw data from selected input channels
timestamp data
CJC sensor readings
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USB-5203 User's Guide

Introducing the USB-5203

You can specify the number of seconds between samples. You can begin logging data at power up, when youpress the data logging button, or at a specific date and time.
Data is stored on the memory card in binary files. After logging measurements, you can transfer the files to yourcomputer. You can use InstaCal to convert the files to .csv format for use in Microsoft Excel files, or to .txt
format for use in other applications.

Functional block diagram
USB-5203 functions are illustrated in the block diagram shown here.

Figure 1. Functional block diagram

7

Chapter 2

Installing the USB-5203
UnpackingAs with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the device from its packaging, ground yourself using a wrist strap or by simply
touching the computer chassis or other grounded object to eliminate any stored static charge.
Contact us immediately if any components are missing or damaged.

Installing the software
Refer to the MCC DAQ Quick Start for instructions on installing the software on the MCC DAQ CD. Refer tothe device product page on the Measurement Computing website for information about the included andoptional software supported by the USB-5203.
Install the software before you install your device
The driver needed to run the USB-5203 is installed with the software. Therefore, you need to install thesoftware package you plan to use before you install the hardware.

Installing the hardware
To connect the USB-5203 to your system, turn your computer on, and connect the USB cable to a USB port onyour computer or to an external USB hub that is connected to your computer. The USB cable provides powerand communication to the USB-5203.
If you are connecting the USB-5203 to an external self-powered hub, connect the USB hub to the computer
before you connect the device to the hub. This ensures that the device detects the hub as an active USB port.

Firmware revision 2.12 and earlier
When you connect the USB-5203 for the first time, a Found New Hardware dialog opens when the operating
system detects the device. When the dialog closes, the installation is complete. The device LED will blink andthen remain on. This indicates that communication is established between the USB-5203 and your computer.

Firmware revision 3.0 and later
The USB-5203 installs as a composite device with separate devices attached. When you connect the USB-5203
for the first time, a Found New Hardware dialog opens as each USB-5203 interface is detected.
It is normal for multiple dialogs to open when you connect the USB-5203 for the first time. For additional
information, refer to the "Notes on installing and using the USB-5201 and USB-5203 data logging devices" thatships with the device.
When the last dialog closes the installation is complete. The LED on the USB-5203 will blink and then remain
on. This indicates that communication is established between the USB-5203 and your computer.
Caution! Do not disconnect any device from the USB bus while the computer is communicating with theUSB-5203, or you may lose data and/or your ability to communicate with the USB-5203.
If the LED turns off
If the LED is lit but then turns off, the computer has lost communication with the USB-5203. To restore
communication, disconnect the USB cable from the computer, and then reconnect it. This should restore
communication, and the LED should turn back on.

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USB-5203 User's Guide

Installing the USB-5203

Configuring the hardware
All hardware configuration options on the USB-5203 are software-selectable. The configurable options
dynamically update according to the selected sensor category. All hardware configuration options on the USB5203 are software-selectable. Settings are stored on an isolated microcontroller in EEPROM – which is nonvolatile memory on the USB-5203 – and are loaded on power-up.
Default configuration
The factory default sensor type configuration is Disabled. The disabled mode disconnects the analog inputs
from the terminal blocks and internally grounds all of the A/D inputs. This mode also disables each of thecurrent excitation sources.

Warm up
Allow the USB-5203 to warm up for 30 minutes before taking measurements. This warm up time minimizes
thermal drift and achieves the specified rated accuracy of measurements. For RTD or thermistor measurements,
this warm-up time is also required to stabilize the internal current reference.

Configuring data logging options
The following data logging options are programmable with software.







select the input channels to log
set the data format
set the start mode
set up alarm conditions
copy and convert saved binary files
delete data files

All data logging options are stored on the USB-5203 in non-volatile memory in EEPROM, and are loaded on
power up.

Calibrating the hardware
Factory calibration
The Measurement Computing Manufacturing Test department performs the initial factory calibration. Returnthe device to Measurement Computing Corporation when calibration is required. The recommended calibrationinterval is one year.

Field-calibration
The USB-5203 supports field-calibration with InstaCal. Calibrate the device whenever the ambient temperaturechanges by more than ±10 °C from the last self-calibration.
Allow the USB-5203 to operate for at least 30 minutes before calibrating.

9

Chapter 3

Sensor Connections
The USB-5203 supports the following temperature sensor types:
 Thermocouple – types J, K, R, S, T, N, E, and B
 Resistance temperature detectors (RTDs) – 2, 3, or 4-wire measurement modes of 100 Ω platinum RTDs.
 Thermistors – 2, 3, or 4-wire measurement modes.
 Semiconductor temperature sensors – LM36 or equivalentSensor selection
The type of sensor you select will depend on your application needs. Review the temperature ranges andaccuracies of each sensor type to determine which is best suited for your application.

Screw terminal pin out
The USB-5203 has four rows of screw terminals – two rows on the top edge of the housing, and two rows on
the bottom edge. Each row has 26 connections. Between each bank of screw terminals are two integrated CJC
sensors used for thermocouple measurements. Signals are identified in Figure 2.

Figure 2. USB-5203 screw terminal pin numbers

Use 16 AWG to 30 AWG wire for your signal connections.
Tighten screw terminal connections
When making connections to the screw terminals, fully tighten the screw. Simply touching the top of the screw
terminal is not sufficient to make a proper connection.

Sensor input terminals (C0H/C0L to C7H/C7L)
You can connect up to eight temperature sensors to the differential sensor inputs (C0H/C0L to C7H/C7L).
Supported sensor categories include thermocouples, RTDs, thermistors, or semiconductor sensors.
Do not mix sensor categories within channel pairs. It is permitted to mix thermocouple types (J, K, R, S, T, N,
E, and B) within channel pairs, however.

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USB-5203 User's Guide

Sensor Connections

Do not connect two different sensor categories to the same channel pair
The USB-5203 provides a 24 bit A/D converter for each channel pair. Each channel pair can monitor one sensor
category. To monitor a sensor from a different category, connect the sensor to a different channel pair (input
terminals).

Current excitation output terminals (±I1 to ±I4)
The USB-5203 has four dedicated pairs of current excitation output terminals (±I1 to ±I4). These terminals havea built-in precision current source to provide excitation for the resistive sensors used for RTD and thermistor
measurements.
Each current excitation terminal is dedicated to one pair of sensor input channels:I1+ is the current excitation source for channel 0 and channel 1
I2+ is the current excitation source for channel 2 and channel 3
I3+ is the current excitation source for channel 4 and channel 5
I4+ is the current excitation source for channel 6 and channel 7

Four-wire, two sensor common terminals (4W01 to 4W67)
These terminals are used as the common connection for four-wire configurations with two RTD or thermistor
sensors.

Two sensor common terminals (IC01 to IC67)
These terminals are used as the common connection for two-wire configurations with two RTD or thermistor
sensors.

Digital terminals (DIO0 to DIO7)
You can connect up to eight digital I/O lines to the screw terminals labeled DIO0 to DIO7. Each terminal issoftware-configurable for input or output.
If a digital bit is set up as an alarm, the bit is configured for output on power-up, and assumes the state definedby the alarm configuration.

CJC sensors
The USB-5203 has two built in high-resolution temperature sensors. One sensor is located on the right side of
the package, and one sensor is located on the left side.

Power terminals (+5V)
The two +5V output terminals are isolated (500 VDC) from the USB +5V.
Caution! Each +5V terminal is an output. Do not connect to an external power supply to these terminals or
you may damage the USB-5203 and possibly the computer.

Ground terminals (GND)
The six ground terminals (GND) provide a common ground for the input channels and DIO bits and are isolated(500 VDC) from the USB GND.

Thermocouple connections
The USB-5203 makes fully-differential thermocouple measurements without the need of ground-referencing
resistors. A 32-bit floating point value in either a voltage or temperature format is returned by software. An
open thermocouple detection feature is available for each analog input which automatically detects an open or
broken thermocouple.
Use InstaCal to select the thermocouple type (J, K, R, S, T, N, E, and B) and one or more sensor input channels
to connect the thermocouple.
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USB-5203 User's Guide

Sensor Connections

Wiring configuration
Connect the thermocouple to the USB-5203 using a differential configuration, as shown in Figure 3.

Figure 3. Typical thermocouple connection

The USB-5203 GND pins are isolated from earth ground, so connecting thermocouple sensors to voltages
referenced to earth ground is permissible as long as the isolation between the GND pins (9, 19, 28, 38) and earth
ground is maintained.
When thermocouples are attached to conductive surfaces, the voltage differential between multiple
thermocouples must remain within ±1.4 V. For best results, we recommend the use of insulated or ungrounded
thermocouples when possible.
Maximum input voltage between analog input and ground
The absolute maximum input voltage between an analog input and the isolated GND pins is ±25 VDC when theUSB-5203 is powered on, and ±40 VDC when the USB-5203 is powered off.
If you need to increase the length of your thermocouple, use the same type of thermocouple wires to minimize
the error introduced by thermal EMFs.

RTD and thermistor connections
A resistance temperature detector (RTD) measures temperature by correlating the resistance of the RTD
element with temperature. A thermistor is a thermally-sensitive resistor that is similar to an RTD in that its
resistance changes with temperature – thermistors show a large change in resistance that is proportional to asmall change in temperature. The main difference between RTD and thermistor measurements is the method
used to linearize the sensor data.
RTDs and thermistors are resistive devices that require an excitation current to produce a voltage drop that canbe measured differentially across the sensor. The device has four built-in current excitation sources (±I1 to ±I4)
for measuring resistive type sensors. Each current excitation terminal is dedicated to one channel pair.
The USB-5203 makes two, three, and four-wire measurements of RTDs (100 Ω platinum type) and thermistors.
Use InstaCal to select the sensor type and the wiring configuration. Once the resistance value is calculated, thevalue is linearized in order to convert it to a temperature value. A 32-bit floating point value in either
temperature or resistance is returned by software.
RTD maximum resistanceResistance values greater than 660 Ω cannot be measured in RTD mode. The 660 Ω resistance limit includes thetotal resistance across the current excitation (±Ix) pins, which is the sum of the RTD resistance and the leadresistances.
Thermistor maximum resistanceResistance values greater than 180 kΩ cannot be measured in thermistor mode. The 180 kΩ resistance limit
includes the total resistance across the current excitation (±Ix) pins, which is the sum of the thermistor
resistance and the lead resistance.

12USB-5203 User's Guide

Sensor Connections

Two-wire configuration
The easiest way to connect an RTD sensor or thermistor to the USB-5203 is with a two-wire configuration,
since it requires the fewest connections to the sensor. With this method, the two wires that provide the RTD
sensor with its excitation current also measure the voltage across the sensor.
Since RTDs exhibit a low nominal resistance, measurement accuracy can be affected due to the lead wire
resistance. For example, connecting lead wires that have a resistance of 1 Ω (0.5 Ω each lead) to a 100 Ω
platinum RTD will result in a 1% measurement error.
With a two-wire configuration, you can connect either one sensor per channel pair, or two sensors per channel
pair.
Two-wire, single-sensor
A two-wire single-sensor measurement configuration is shown in Figure 4.

Figure 4. Two-wire, single RTD or thermistor sensor measurement configuration

When you select a two-wire single sensor configuration with InstaCal, connections to C#H and C#L are madeinternally.
Two-wire, two sensor
A two-wire, two-sensor measurement configuration is shown in Figure 5.

Figure 5. Two-wire, two RTD or thermistor sensors measurement configuration

When you select a two-wire, two sensor configuration with InstaCal, connections to C#H (first sensor) andC#H/C#L (second sensor) are made internally.
When configured for two-wire mode, both sensors must be connected to obtain proper measurements.

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USB-5203 User's Guide

Sensor Connections

Three-wire configuration
A three-wire configuration compensates for lead-wire resistance by using a single-voltage sense connection.
With a three-wire configuration, you can connect only one sensor per channel pair. A three-wire measurement
configuration is shown in Figure 6.

Figure 6. Three-wire RTD or thermistor sensor measurement configuration

When you select a three-wire sensor configuration with InstaCal, the USB-5203 measures the lead resistance on
the first channel (C#H/C#L) and measures the sensor itself using the second channel (C#H/C#L). Thisconfiguration compensates for any lead-wire resistance and temperature change in lead-wire resistance.
Connections to C#H for the first channel and C#H/C#L of the second channel are made internally.
Three-wire compensation
For accurate three wire compensation, the individual lead resistances connected to the ±I# pins must be of equal
resistance value.

Four-wire configuration
With a four-wire configuration, connect two sets of sense/excitation wires at each end of the RTD or thermistor
sensor. This configuration completely compensates for any lead-wire resistance and temperature change in leadwire resistance.
Connect your sensor with a four-wire configuration when your application requires very high accuracy
measurements. Examples of a four-wire single-sensor measurement configuration are shown in Figure 7 andFigure 8.
You can configure the USB-5203 with either a single-sensor-per-channel, or a two-sensor–per-channel pair.
Four-wire, single-sensor
A four-wire, single-sensor connected to the first channel of a channel pair is shown in Figure 7.

Figure 7. Four-wire, single RTD or thermistor sensor measurement configuration

A four-wire, single-sensor connected to the second channel of a channel pair is shown in Figure 8.

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USB-5203 User's Guide

Sensor Connections

Figure 8. Four-wire, single RTD or thermistor sensor measurement configuration

A four-wire, two-sensor measurement configuration is shown in Figure 9.

Figure 9. Four-wire, two RTD or thermistor sensors measurement configuration

When configured for two-wire mode, both sensors must be connected to obtain proper measurements.

Semiconductor sensor measurements
Semiconductor sensors are suitable over a range of approximately -40 °C to 125 °C, where an accuracy of±2 °C is adequate. The temperature measurement range of a semiconductor sensor is small when compared tothermocouples and RTDs. However, semiconductor sensors can be accurate, inexpensive and easy to interface
with other electronics for display and control.
The USB-5203 makes high-resolution measurements of semiconductor sensors. The software outputs themeasurement data as a 32-bit floating point value in either voltage or temperature.
Use InstaCal to select the sensor type (LM35, TMP35 or equivalent) and the sensor input channel to connect thesensor.

Wiring configuration
Connect the semiconductor sensor to the USB-5203 using a single-ended configuration, as shown in Figure 10.
The device provides +5V and GND pins for powering the sensor.

Figure 10. Semiconductor sensor measurement configuration

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USB-5203 User's Guide

Sensor Connections

Digital I/O connections
You can connect up to eight digital I/O lines to the screw terminals labeled DIO0 to DIO7. All digital I/O lines
are pulled up to +5V with a 47 kΩ resistor (default). You can request the factory to configure the resistor for
pull-down to ground if desired. You can configure each digital bit for either input or output.
Caution! If a digital bit is set up as an alarm, the bit will be configured for output on power-up, and assume
the state defined by the alarm configuration.
When you configure the digital bits for input, you can use the USB-5203 digital I/O terminals to detect the stateof any TTL-level input. Refer to the schematic shown in Figure 11. If you set the switch to the +5V input, DIO0
reads TRUE (1). If you move the switch to GND, DIO0 reads FALSE (0).

Figure 11. Schematic showing switch detection by digital channel DIO0

Caution! All ground pins on the USB-5203 (pins 9, 19, 28, 38) are common and are isolated from earth
ground. If a connection is made to earth ground when using digital I/O and conductive
thermocouples, the thermocouples are no longer isolated. In this case, thermocouples must not be
connected to any conductive surfaces that may be referenced to earth ground.
For general information regarding digital signal connections and digital I/O techniques, refer to the Guide to
Signal Connections (available on our web site at www.mccdaq.com/signals/signals.pdf).

Configuring the DIO channels to generate alarms
The USB-5203 features eight independent temperature alarms. All alarm options are software configurable.
When a digital bit is configured as an alarm, that bit will be configured as an output on the next power cycle andassume the state defined by the alarm configuration.
Each alarm controls an associated digital I/O channel as an alarm output. The input to each alarm is one of thetemperature input channels. You set up the temperature conditions to activate an alarm, and the output state of
the channel (active high or low) when activated. When an alarm is activated, its associated DIO channel isdriven to the output state specified.
The alarm configurations are stored in non-volatile memory and are loaded on power up. The temperature
alarms function both in data logging mode and while attached to the USB port on a computer.

16

Chapter 4

Functional Details
Thermocouple measurements
A thermocouple consists of two dissimilar metals that are joined together at one end. When the junction of themetals is heated or cooled, a voltage is produced that correlates to temperature.
The USB-5203 hardware level-shifts the thermocouple’s output voltage into the A/D’s common mode input
range by applying +2.5 V to the thermocouple’s low side at the C#L input. Always connect thermocouple
sensors to the USB-5203 in a floating fashion. Do not attempt to connect the thermocouple low side C#L to
GND or to a ground referencing resistor.

Cold junction compensation (CJC)
When you connect the thermocouple sensor leads to the sensor input channel, the dissimilar metals at the USB5203 terminal blocks produce an additional thermocouple junction. This junction creates a small voltage error
term which must be removed from the overall sensor measurement using a cold junction compensation
technique. The measured voltage includes both the thermocouple voltage and the cold junction voltage. To
compensate for the additional cold junction voltage, the USB-5203 subtracts the cold junction voltage from thethermocouple voltage.
The USB-5203 has two high-resolution temperature sensors that are integrated into the design of the USB-5203.
One sensor is located on the right side of the package, and one sensor is located at the left side. The CJC sensors
measure the average temperature at the terminal blocks so that the cold junction voltage can be calculated. A
software algorithm automatically corrects for the additional thermocouples created at the terminal blocks bysubtracting the calculated cold junction voltage from the analog input's thermocouple voltage measurement.
Increasing the thermocouple length
If you need to increase the length of your thermocouple, use the same type of thermocouple wires to minimize
the error introduced by thermal EMFs.

Data linearization
After the CJC correction is performed on the measurement data, an on-board microcontroller automaticallylinearizes the thermocouple measurement data using National Institute of Standards and Technology (NIST)
linearization coefficients for the selected thermocouple type.
The measurement data is then output as a 32-bit floating point value in the configured format (voltage ortemperature).

Open-thermocouple detection (OTD)
The USB-5203 is equipped with an open-thermocouple detection for each analog input channel. With OTD, any
open-circuit or short-circuit condition at the thermocouple sensor is detected by the software. An open channel
is detected by driving the input voltage to a negative value outside the range of any thermocouple output. The
software recognizes this as an invalid reading and flags the appropriate channel. The software continues tosample all channels when OTD is detected.
Input leakage current
With open-thermocouple detection enabled, 105 nA (max.) of input leakage current is injected into thethermocouple. This current can cause an error voltage to develop across the lead resistance of the thermocouple
that is indistinguishable from the thermocouple voltage you are measuring. You can estimate this error voltage
with the following formula:error voltage = resistance of the thermocouple x 105 nA

To reduce the error, reduce the length of the thermocouple to lower its resistance, or lower the AWG of the wireby using a wire with a larger diameter. With open-thermocouple detection disabled, 30 nA (max) of input
leakage current is injected into the thermocouple.
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USB-5203 User's Guide

Functional Details

RTD and thermistor measurements
RTDs and thermistors are resistive devices that require an excitation current to produce a voltage drop that canbe measured differentially across the sensor. The USB-5203 measures the sensor resistance by forcing a known
excitation current through the sensor and then measuring (differentially) the voltage across the sensor todetermine its resistance.
After the voltage measurement is made, the resistance of the RTD is calculated using Ohms law – the sensor
resistance is calculated by dividing the measured voltage by the current excitation level (±Ix) source. The valueof the ±Ix source is stored in local memory.
Once the resistance value is calculated, the value is linearized in order to convert it to a temperature value. The
measurement is returned by software as a 32-bit floating point value in a voltage, resistance or temperatureformat.

Data linearization
An on-board microcontroller automatically performs linearization on RTD and thermistor measurements.


RTD measurements are linearized using a Callendar-Van Dusen coefficients algorithm (you select DIN,
SAMA, or ITS-90).
Thermistor measurements are linearized using a Steinhart-Hart linearization algorithm (you supply thecoefficients from the sensor manufacturer's data sheet).

External components
The USB-5203 has the following external components, as shown in Figure 12.

1
2
3

Screw terminal pins 1 to 26
Screw terminal pins 27 to 52
LED

4
5
6

Data logging button
CompactFlash® memory card slot (with card)
USB connector

Figure 12. External component locations

Screw terminals
Use the screw terminals for connecting temperature sensors and digital I/O lines. These terminals also provide
ground and power output connections. Refer to the "Sensor Connections" chapter for screw terminal
descriptions.

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USB-5203 User's Guide

Functional Details

USB connector
When not logging data, connect the USB cable to a USB port on your computer or to an external USB hub thatis connected to your computer. When connected to an active USB bus, the USB connector provides +5 V powerand communication. The voltage supplied through the USB connector is system-dependent, and may be lessthan 5 V. No external power supply is required.
Due to processing limitations, you cannot log data when the device is attached to an active USB bus. For data
logging operations, connect the USB connector to the external power supply.

LED
The LED uses up to 5 mA of current. The function of the LED varies according to whether the USB-5203 isconnected to an active USB port, or when the device is logging data and connected to the external power
supply.
Refer to the table below for the function of the USB-5203 LED when the device is connected to an active USB
port and not logging data.
LED function when the USB-5203 is connected to an active USB port
LED Illumination

Indication

Steady green
Blinks continuously

The USB-5203 is connected to a computer or external USB hub.
Data is being transferred.
Upon connection, the LED should flash a few times and then remain lit (indicates a successful
installation).
Initial communication is established between the USB-5203 and the computer.
The USB-5203 is not connected to an active USB port.

Blinks several times
Off

Refer to the table below for the function of the USB-5203 LED when the device is connected to the external
supply and is logging data. The function of the LED varies according to the selected logging mode.
LED function when the USB-5203 is logging data
Logging mode

LED Illumination

Indication

Logging off

The LED is off.

Start Logging on Power
Up
Start Logging on Button

The LED turns on when external power isconnected, then blinks each time data is captured.
The LED stays off until the data logging button ispressed and held for approximately 1 second. Atthat time, the LED turns on and blinks each time
data is captured.
The LED is off – blinks on once per second until
the specified date/time to start logging is reached.
At that time, the LED turns on – blinks off eachtime data is captured.
Blinks rapidly (250 ms period) and continuously.

The USB-5203 is not logging data, and/or
the device is not powered
Blinks when logging data.

Start Logging at
Specified TimeAny logging mode

Blinks when logging data.

Blinks on once per second until specified
data/time to log data occurs. Then it turns
on and blinks each time data is captured.
The memory card is full.
The memory card was removed during
logging. Insert the memory card again
to stop the device blinking.

CompactFlash® memory card slot
The CompactFlash slot accepts standard memory cards. A 512 MB memory card is shipped with the device. For
extensive data logging, you can insert a higher capacity card of up to 2 GB. You must format the memory card
before logging data for the first time.

19USB-5203 User's Guide

Functional Details

Calculating the logging time for a memory card
Use the following formula to calculate the approximate amount of logging time in seconds that one of the
supported memory card allows. The USB-5203 supports 512 MB , 1 GB, and 2 GB CompactFlash memory
cards.

where










time = total disk time in seconds
NDisk = size of memory card in bytes
NDIO = 1 byte for digital I/OnChannels = number of channels logged

R = logging rate in seconds
NTS = 6 bytes for timestamp, if enabled
NTemp = 4 bytes for a temperature reading
NCJC = 8 bytes if CJC sensor readings areenabledThe following table provides examples of logging one channel and eight channels of temperature readings at the
max logging rate of 1 S/s to a 512 MB memory card with DIO, timestamp, and CJC sensor logging enabled:
Memory card(bytes)

DIO enabled

Number ofchannels

Logging
rate (S/s)

Timestamp
enabledTemperature
reading

CJC
enabled512,000,000

1

1

1

6

4

8

512,000,000

1

8

1

6

4

8

Data logging button
Use the data logging button to end a data logging session. The data logging button is also used to start recording
data when the logging mode is set in InstaCal to Start Logging on Button.


To begin recording data, press and hold the button until the LED begins to blink. The first sample is taken
one second after the LED illuminates.
When you first power on the USB-5203, wait at least five seconds before pressing the data logging button.
To achieve rated accuracy, allow the USB-5203 to warm up for 30 minutes before logging data.
To stop recording data, press and hold the button again until the LED is off.

Caution! To prevent loss of data, always use the button to stop logging. Make sure the data is written to thememory card before you disconnect the device from the power source.
The device caches log data in volatile memory prior to writing to the memory card.
Pressing the data logging button has no effect when the USB-5203 is connected to an active USB port and not
logging data.
External power required for data logging
Due to processing limitations, data logging is not allowed when the USB-5203 is attached to an active USB bus.
The USB-5203 must be connected to the standalone power supply to perform data logging.

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USB-5203 User's Guide

Functional Details

External power supply
The external power supply is a 2.5 W USB power adapter used to power the device during data logging
operations.

Disconnecting the USB-5203 from the computer
You don't need to shut down your computer to disconnect the USB-5203. Refer to the instructions below when
disconnecting the USB-5203 from your computer's USB port.
When the USB-5203 is installed with firmware revision 3 or later and you are running Windows XP, use theUnplug or Eject icon on the computer's taskbar to safely stop the USB-5203 before you unplug it. To do this,right-click on the icon, select the USB-5203 and click Stop. Windows will notify you when it is safe to
disconnect the device from your computer.

Transferring binary data after a logging session
Data is stored on the memory card in binary files. After logging measurements, you can transfer the files to yourcomputer by reconnecting the USB-5203 to a USB port on your computer or by removing the CompactFlashcard from the USB-5203 and using a card reader connected to your computer.
Note that when installed with firmware version 3 and later the USB-5203 appears as a Mass Storage Device
when connected to a USB port on your computer, so you can copy files using Windows Explorer.

Converting binary data after a logging session
If your USB-5203 is connected to a USB port on your computer, you can use InstaCal or TracerDAQ to convert
the files on the CompactFlash card to .CSV format for use in Microsoft Excel files, or to .TXT format for use inother applications.
If you transferred binary files to your computer hard drive or removed the CompactFlash card from yourUSB-5203 and are using a card reader connected to your computer, use TracerDAQ to import the files and savethem as .csv or.txt format. InstaCal can only convert files when the CompactFlash card is in a USB-5203
connected to your computer.

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Chapter 5

Specifications
All specifications are subject to change without notice.
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.

Analog input
Table 1. Generic analog input specifications
Parameter

Conditions

Specification

A/D converters
Number of channels
Input isolation
Channel configuration
Differential input voltage
range for the various sensor
categories

Absolute maximum input
voltage
Input impedance
Input leakage current

Normal mode rejection ratio
Common mode rejection
Ratio
Resolution
No missing codes
Input couplingWarm-up time
Open thermocouple detect

CJC sensor accuracy

Thermocouple
RTD
Thermistor
Semiconductor sensor±C0x through ±C7x relative to GND(pins 9, 19, 28, 38)

Four dual 24-bit, Sigma-Delta type
8 differential
500 VDC minimum between field wiring and USB
interface
Software programmable to match sensor type±0.080 V
0 V to 0.5 V
0 V to 2 V
0 V to 2.5 V±25 V power on, ±40 V power off

Open thermocouple detect disabled

5 GΩ, min
30 nA maxOpen thermocouple detect enabled
fIN = 60 Hz
fIN=50 Hz/60 Hz

105 nA max
90 dB min
100 dB min

15 °C to 35 °C
0 °C to 70 °C

24 bits
24 bitsDC
30 minutes min
Automatically enabled when the channel pair isconfigured for thermocouple sensor.
The maximum open detection time is 3 seconds.
±0.25 °C typ,±0.5 °C max–1.0 °C to +0.5 °C max

Channel configurations
Internally, the device has four, dual-channel, fully differential A/Ds providing a total of eight differential
channels. The analog input channels are therefore configured in four channel pairs with CH0/CH1 sensor
inputs, CH2/CH3 sensor inputs, CH4/CH5 sensor inputs, and CH6/CH7 sensor inputs paired together. This
channel-pairing requires the analog input channel pairs be configured to monitor the same category oftemperature sensor. Mixing different sensor types of the same category (such as a type J thermocouple onchannel 0 and a type T thermocouple on channel 1) is valid.
Channel configuration information is stored in the EEPROM of the isolated microcontroller by the firmware
whenever any item is modified. Modification is performed by commands issued over USB from an external
application, and the configuration is made non-volatile through the use of the EEPROM.

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Specifications

Table 2. Channel configuration specifications
Sensor Category

Disabled (Note 1)
Thermocouple
Semiconductor sensor
RTD and thermistor

Conditions

Max number of
sensors (all channels
configured alike)

J, K, S, R, B, E, T, or N

8 differential channels
8 differential channels
4 differential channels
8 differential channels
4 differential channels
4 differential channels
8 differential channels

2-wire input configuration with a single sensor per channel pair2-wire input configuration with two sensors per channel pair
3-wire configuration with a single sensor per channel pair
4-wire input configuration with a single sensor per channel pair
4-wire input configuration with two sensors per channel pair

Note 1: The factory default configuration is Disabled. In Disabled mode, analog inputs are disconnected fromthe terminal blocks and all of the A/D inputs are internally grounded. This mode also disables each of
the current excitation sources.

Compatible sensors
Table 3. Compatible sensor type specifications
Parameter

Specification (°C)

Thermocouple

J: –210 to 1200
K: –270 to 1372
R: –50 to 1768
S: –50 to 1768
T: –270 to 400
N: –270 to 1300
E: –270 to 1000
B: 0 to 1820
100 Ω PT (DIN 43760: 0.00385 ohms/ohm/°C)
100 Ω PT (SAMA: 0.003911 ohms/ohm/°C)
100 Ω PT (ITS-90/IEC751:0.0038505 ohms/ohm/°C)Standard 2,252 Ω through 30,000 Ω
LM35, TMP35 or equivalent

RTD

Thermistor
Semiconductor / IC

Accuracy
Thermocouple measurement accuracy
Thermocouple measurement accuracy specifications include linearization, cold-junction compensation andsystem noise. These specs are for one year, or 3000 operating hours, whichever comes first, and for operation of
the device between 15 °C and 35 °C. For measurements outside this range, add ±0.5° to the maximum error
shown. There are CJC sensors on each side of the module. The accuracy listed above assumes the screw
terminals are at the same temperature as the CJC sensor. Errors shown do not include inherent thermocouple
error. Please contact your thermocouple supplier for details on the actual thermocouple error.
Thermocouples must be connected to the device such that they are floating with respect to GND (pins 9, 19, 28,38). The device GND pins are isolated from earth ground, so connecting thermocouple sensors to voltages
referenced to earth ground is permissible as long as the isolation between the GND pins and earth ground ismaintained.
When thermocouples are attached to conductive surfaces, the voltage differential between multiple
thermocouples must remain within ±1.4 V. For best results, MCC recommends using insulated or ungrounded
thermocouples when possible.
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USB-5203 User's Guide

Specifications

Table 4. Thermocouple accuracy specifications, including CJC measurement error
Sensor TypeMaximum error (°C)

Typical error (°C)

Temperature range (°C)

J

±1.499±0.643±1.761±0.691±2.491±1.841±2.653±1.070±1.779±0.912±1.471±0.639±1.717±0.713±1.969±0.769±0.507±0.312±0.538±0.345±0.648±0.399±0.650±0.358±0.581±0.369±0.462±0.245±0.514±0.256±0.502±0.272–210 to 0
0 to 1200–210 to 0
0 to 1372–50 to 250
250 to 1768.1–50 to 250
250 to 1768.1
250 to 700
700 to 1820
–200 to 0
0 to 1000–200 to 0
0 to 600–200 to 0
0 to 1300

K
S
R
B
E
T
N

Semiconductor sensor measurement accuracy
The error shown in Table 5 below does not include errors of the sensor itself. These specs are for one year while
operation of the device is between 15 °C and 35 °C. Please contact your sensor supplier for details on the actual
sensor error limitations.
Table 5. Semiconductor sensor accuracy specifications
Sensor Type

Temperature Range (°C)

Maximum Accuracy Error (°C)

LM35, TMP35 or equivalent–40 to 150±0.50 (Note 2)

RTD measurement accuracy
The error shown in Table 6 below does not include errors of the sensor itself. The sensor linearization is
performed using a Callendar-Van Dusen linearization algorithm. These specs are for one year while operating
the device between 15 °C and 35 °C. The specification does not include lead resistance errors for 2-wire RTD
connections. Please contact your sensor supplier for details on the actual sensor error limitations.
In RTD mode, the device cannot measure resistance values greater than 660 Ω. The 660 Ω resistance limit
includes the total resistance across the current excitation (Ix+/Ix–) pins, which is the sum of the RTD resistanceand the lead resistances.
For accurate three-wire compensation, the individual lead resistances connected to the Ix+/Ix– pins must be ofequal value.
Table 6. RTD measurement accuracy specifications
RTD

SensorTemperature (°C)

Maximum Accuracy Error (°C)
Ix+ = 210 µA

Typical Accuracy Error (°C)
Ix+ = 210 µA

PT100, DIN, US
or ITS-90–200 to –150
–150 to –100
–100 to 0
0 to 100
100 to 300
300 to 600

±2.85
±1.24
±0.58
±0.38
±0.39
±0.40

±2.59
±0.97
±0.31
±0.11
±0.12
±0.12

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USB-5203 User's Guide

Specifications

Thermistor measurement accuracy
The error shown in Table 7 below does not include errors of the sensor itself. The sensor linearization is
performed using a Steinhart-Hart linearization algorithm. These specs are for one year while operating thedevice between 15 °C and 35 °C. The specification does not include lead resistance errors for 2-wire thermistor
connections. Please contact your sensor supplier for details on the actual sensor error limitations.
Total thermistor resistance on any given channel pair must not exceed 180 kΩ (refer to Table 8 below).
Table 7. Thermistor measurement accuracy specifications
Thermistor

Temperature Range (°C)

Maximum Accuracy Error (°C)
Ix+ = 10 µA

2252 Ω

–40 to120±0.05

3000 Ω
5000 Ω

–40 to120–35 to120

±0.05
±0.05

10000 Ω30000 Ω–25 to120–10 to120

±0.05
±0.05

Typical resistance values at various temperatures for supported thermistors are shown in Table 8 below.
The device cannot measure resistance values greater than 180 kΩ in thermistor mode. The 180 kΩ resistancelimit includes the total resistance across the current excitation (Ix+/Ix–) pins, which is the sum of the thermistor
resistance and the lead resistances.
For accurate three-wire compensation, the individual lead resistances connected to the Ix+/Ix– pins must be ofequal value.
Table 8. Typical thermistor resistance specifications
Temp
(°C)

2252 Ω
thermistor

3000 Ω thermistor

5 kΩ thermistor

10 kΩ thermistor

30 kΩ thermistor

–40
–35

76 kΩ
55 kΩ

101 kΩ
73 kΩ

168 kΩ
121 kΩ

240 kΩ
179 kΩ

885 kΩ
649 kΩ

–30
–25

40 kΩ
29 kΩ

53 kΩ
39 kΩ

88 kΩ
65 kΩ

135 kΩ
103 kΩ

481 kΩ
360 kΩ

–20
–15

22 kΩ
16 kΩ

29 kΩ
22 kΩ

49 kΩ
36 kΩ

79 kΩ
61 kΩ

271 kΩ
206 kΩ

–10
–5

12 kΩ
9.5 kΩ

17 kΩ
13 kΩ

28 kΩ
21 kΩ

48 kΩ
37 kΩ

158 kΩ
122 kΩ

0

7.4 kΩ

9.8 kΩ

16 kΩ

29 kΩ

95 kΩ

Throughput rate to PC
The analog inputs are configured to run continuously. Each channel is sampled twice per second. The maximum
latency between when a sample is acquired and the temperature data is provided by the USB unit isapproximately 0.5 seconds.
Maximum throughput to a CompactFlash® memory card is 1 S/s per channel.

25

USB-5203 User's Guide

Specifications

Table 9. Throughput rate specifications
Number of Input
Channels

Maximum Throughput

1
2
3
4
5
6
7
8

2 Samples/second
2 S/s on each channel, 4 S/s total
2 S/s on each channel, 6 S/s total
2 S/s on each channel, 8 S/s total
2 S/s on each channel, 10 S/s total
2 S/s on each channel, 12 S/s total
2 S/s on each channel, 14 S/s total
2 S/s on each channel, 16 S/s total

Digital input/output
Table 10. Digital input/output specifications
Parameter

Specification

Digital type
Number of I/O
Configuration

CMOS
8 (DIO0 through DIO7)
Independently configured for input or output.
Power on reset is input mode unless bit is configured for alarm.
All pins pulled up to +5 V via 47 K resistors (default). Pull down to ground (GND) alsoavailable.
 Digital input – 50 port reads or single bit reads per second typ
 Digital output – 100 port writes or single bit writes per second typ
2.0 V min, 5.5 V absolute max
0.8 V max, –0.5 V absolute min
0.7 V max

Pull up/pull-down
configuration
Digital I/O transfer rate
(software paced)
Input high voltage
Input low voltage
Output low voltage(IOL = 2.5 mA)
Output high voltage(IOH = –2.5 mA)

3.8 V minNote 2: All ground pins on the device (pins 9, 19, 28, 38) are common and are isolated from earth ground. If aconnection is made to earth ground when using digital I/O and conductive thermocouples, thethermocouples are no longer isolated. In this case, thermocouples must not be connected to any
conductive surfaces that may be referenced to earth ground.

26

USB-5203 User's Guide

Specifications

Temperature alarms
Table 11. Temperature alarm specifications
Parameter

Specification

Number of alarms
Alarm functionality

8 (one per digital I/O line)
Each alarm controls its associated digital I/O line as an alarm output. The input to each
alarm may be any of the analog temperature input channels. When an alarm is enabled, its
associated I/O line is set to output (after the device is reset) and driven to the appropriate
state determined by the alarm options and input temperature. The alarm configurations
are stored in non-volatile memory and are loaded at power on. Alarms function both indata logging mode and while attached to USB.
 Alarm when input temperature > T1
 Alarm when input temperature > T1, reset alarm when input temperature goes below
T2
 Alarm when input temperature < T1
 Alarm when input temperature < T1, reset alarm when input temperature goes above
T2
 Alarm when input temperature is < T1 or > T2

Alarm input modes

Alarm output modes

Alarm update rate

T1 and T2 may be independently set for each alarm.
 Disabled, digital I/O line may be used for normal operation
 Enabled, active high output (digital I/O line goes high when alarm conditions met) Enabled, active low output (digital I/O line goes low when alarm conditions met)
1 second

MemoryTable 12. Memory specifications
Parameter

Specification

EEPROM

1,024 bytes isolated micro reserved for sensor configuration
256 bytes USB micro for external application use
256 bytes USB micro reserved for data logging configuration

Microcontroller
Table 13. Microcontroller specifications
Parameter

Specification

Type

Two high performance 8-bit RISC microcontrollers

27USB-5203 User's Guide

Specifications

Data Logging
Table 14. Data logging specifications
Parameter

Specification

Standalone power supply

USB power adapter
2.5 watt USB adapter with interchangeable plugs(Includes plug for USA)
CompactFlash512 MB CompactFlash card
USB Mass Storage Device (MSD)
FAT16, FAT32
The device only creates 8.3 file names in the root subdirectory.
binaryMin 1 second between entries, max 232 seconds, 1 second granularity
Timestamp, temperature, or raw reading from selected channels, state of DIO lines, CJC
sensor readings
Configurable: Start Logging on Power Up – Logging begins 5 seconds after power on to allow
hardware to settle.
 Start Logging on Button – Device is idle on power on. Press and hold the button
until the LED turns on to begin logging. The first sample is acquired 1 second after the
LED turns on unless less than 5 seconds have elapsed since power on.
 Start Logging at Specified Time – Device is idle until the real-time clock
indicates the time is equal to or greater than the specified time, at which time the LED
turns on. The first sample is acquired 1 second after the LED turns on unless less than
5 seconds have elapsed since power on.
Stop on button press – To stop logging, press and hold the button until the LED turns off.
The device caches logged data in volatile memory prior to writing to memory card. Whenlogging, always use the button to stop logging and ensure data is written to memory cardprior to removing power.
The LED operations when connected to the AC adapter power supply are different thanwhen connected to USB.
Logging modes:
 Logging Off mode: the LED is off (disabled).
 Start Logging on Power Up mode: the LED turns on, but blinks off momentarily
every time data is captured.
 Start Logging on Button mode: the LED is initially off. When the button is pressedand held for approximately 1 second, the LED turns on and act the same as Start
Logging on Power Up mode.
 Start Logging at Specified Time mode: the LED turns off, with a momentary on
flash every second until the specified date/time is reached. At that time, the LED turns
on and acts the same as Start Logging on Power Up mode.
Other indication:
 To stop logging and store the remaining data to memory card, press and hold the button
until the LED turns off. It is then safe to remove the memory card.
 If the memory card becomes full, the LED blinks rapidly (250 ms period).
 If the memory card is removed while logging is in progress, the LED blinks rapidly(250 ms period). Inserting a memory card stops the LED from blinking.

Memory card type
Supplied memory card
Memory card host access
File systems supported
Log file format
Logging rate
Data items logged
Logging start methods

Logging stop methods

Logging status indication

Real time clock
Table 15. Real time clock specifications
Parameter

Specification

Battery backup
Accuracy

CR-2032 lithium coin cell, replaceable±1 minute per month28

USB-5203 User's Guide

Specifications

USB +5V voltage
Table 16. USB +5 V voltage specifications
Parameter

Specification

USB +5 V (VBUS) input voltage
range

4.75 V min to 5.25 V max

Power
Table 17. Power specifications
Parameter

Conditions

Specification

USB enumeration
Continuous mode
Connected to a self-powered hub. (Note 4)
Connected to a self-powered hub. (Note 4)<100 mA
500 mA max
4.75 V min to
5.25 V max
10 mA max

Measurement system to PC

500 VDC min

Connected to USB
Supply current
Supply current (Note 3)+5 V output voltage range(pins 21 and 47)+5 V output current(pins 21 and 47)
Isolation

AC Adapter Power Supply (used for data logging operation)
Output voltage
Output wattage
Input voltage

5 V ±5%
2.5W
100 VAC to 240 VAC
50 Hz to 60 Hz
0.2 A

Input current

Note 3: This is the total current requirement for the device which includes up to 10 mA for the status LED.
Note 4: Self-powered hub refers to a USB hub with an external power supply. Self-powered hubs allow aconnected USB device to draw up to 500 mA. This device may not be used with bus-powered hubs dueto the power supply requirements.
Root Port Hubs reside in the PC USB host controller. The USB port(s) on your PC are root port hubs.
All externally powered root port hubs (desktop PC) provide up to 500 mA of current for a USB device.
Battery-powered root port hubs provide 100 mA or 500 mA, depending upon the manufacturer. A
laptop PC that is not connected to an external power adapter is an example of a battery-powered root
port hub.

USB specifications
Table 18. USB specifications
Parameter

Specification

USB device type
Device compatibility

USB 2.0 (full-speed)
USB 1.1, USB 2.0
Self-powered, 500 mA consumption max
A-B cable, UL type AWM 2725 or equivalent. (min 24 AWG VBUS/GND,
min 28 AWG D+/D–)
3 m (9.84 ft) max

USB cable type
USB cable length29

USB-5203 User's Guide

Specifications

Current excitation outputs (Ix+)
The device has four current excitation outputs, with I1+/I1– dedicated to the CH0/CH1 analog inputs, I2+/I2–
dedicated to CH2/CH3, I3+/I3– dedicated to CH4/CH5, and I4+/I4– dedicated to CH6/CH7. The excitation
output currents should always be used in this dedicated configuration.
The current excitation outputs are automatically configured based on the sensor (thermistor or RTD) selected.
Table 19. Current excitation output specifications
Parameter

Specification

Configuration

4 dedicated pairs:

Current excitation output ranges
Tolerance
DriftLine regulation
Load regulation
Output compliance voltage (relative
to GND pins 9,19,28,38)

Current excitation output

AI channel

I1+/I1–
I2+/I2–
I3+/I3–
I4+/I4–

CH0/CH1
CH2/CH3
CH4/CH5CH6/CH7

Thermistor: 10 µA typ
RTD: 210 µA typ±5% typ
200 ppm/°C
2.1 ppm/V max
0.3 ppm/V typ
3.90 V max–0.03 V min

Environmental
Table 20. Environmental specifications
Operating temperature range
Storage temperature range
Humidity

0 °C to 70 °C–40 °C to 85 °C
0% to 90% non-condensing

Mechanical
Table 21. Mechanical specifications
Dimensions (L × W × H)User connection length

128.52 x 88.39 × 35.56 mm (5.06 × 3.48 × 1.43 ft)
3 m (9.84 ft) max

Screw terminal connector
Table 22. Screw terminal connector specifications
Connector type

Screw terminal

Wire gauge range

16 AWG to 30 AWG

30

USB-5203 User's Guide

Specifications

Table 23. Screw terminal pinout
Pin
1
2
3
4
5
6
7
8
9
10

Signal Name
I1+
NC
C0H
C0L
4W01
IC01
C1H
C1L
GND
I1–

Pin Description
CH0/CH1 current excitation source
No connection
CH0 sensor input (+)
CH0 sensor input (–)
CH0/CH1 4-wire, 2 sensor common
CH0/CH1 2-sensor common
CH1 sensor input (+)
CH1 sensor input (–)
GroundCH0/CH1 current excitation return

Pin
27
28
29
30
31
32
33
34
35
36

CJC sensor
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26

I2+
NC
C2H
C2L
4W23
IC23
C3H
C3L
GND
I2–
+5V
GND
DIO0
DIO1
DIO2
DIO3

Signal Name Pin Description
I4–
CH6/CH7 current excitation return
GND
GroundC7L
CH7 sensor input (–)
C7H
CH7 sensor input (+)
IC67
CH6/CH7 2 sensor common
4W67
CH6/CH7 4-wire, 2 sensor common
C6L
CH6 sensor input (–)
C6H
CH6 sensor input (+)
NC
No connection
I4+
CH6/CH7 current excitation source
CJC sensor

CH2/CH3 current excitation source
No connection
CH2 sensor input (+)
CH2 sensor input (–)
CH2/CH3 4-wire, 2 sensor common
CH2/CH3 2 sensor common
CH3 sensor input (+)
CH3 sensor input (–)
GroundCH2/CH3 current excitation return
Power output
GroundDIO channel 0
DIO channel 1
DIO channel 2
DIO channel 3

31

37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52

I3–
GND
C5L
C5H
IC45
4W45
C4L
C4H
NC
I3+
+5V
GND
DIO7
DIO6
DIO5
DIO4

CH4/CH5 current excitation return
GroundCH5 sensor input (–)
CH5 sensor input (+)
CH4/CH5 2 sensor common
CH4/CH5 4-wire, 2 sensor common
CH4 sensor input (–)
CH4 sensor input (+)
No connection
CH4/CH5 current excitation source
Power output
GroundDIO channel 7
DIO channel 6
DIO channel 5
DIO channel 4

Declaration of Conformity
Manufacturer:
Address:

Category:

Measurement Computing Corporation
10 Commerce Way
Suite 1008
Norton, MA 02766
USAElectrical equipment for measurement, control and laboratory use.

Measurement Computing Corporation declares under sole responsibility that the productUSB-5203
to which this declaration relates is in conformity with the relevant provisions of the following standards or otherdocuments:
EC EMC Directive 2004/108/EC: Electromagnetic Compatibility, EN 61326-1:2006, (IEC 61326-1:2005)
Emissions:EN 55011 (1990)/CISPR 11 Radiated emissions: Group 1, Class A
EN 55011 (1990)/CISPR 11 Conducted emissions: Group 1, Class A

Immunity: EN61326-1:2006, (IEC 61326-1:2005) Table 3 Immunity requirements for equipment used incontrolled EM environments.


IEC 61000-4-2 (2001): Electrostatic Discharge immunity.
IEC 61000-4-3 (2002): Radiated Electromagnetic Field immunity.

To maintain the safety, emission, and immunity standards of this declaration, the following conditions must be
met.







The host computer, peripheral equipment, power sources, and expansion hardware must be CE compliant.
Equipment must be operated in a controlled electromagnetic environment as defined by Standards EN
61326-1:2006, or IEC 61326-1:2005.
Shielded wires must be used for all I/Os and must be less than 3 meters (9.75 feet) in length.
The host computer must be properly grounded.
The host computer must be USB 2.0 compliant.
A protective ESD wrist strap should be used when connecting or disconnecting leads from screw terminal
blocks.

Note: Data acquisition equipment may exhibit noise or increased offsets when exposed to high RF fields(>1V/m) or transients.
Declaration of Conformity based on tests conducted by Chomerics Test Services, Woburn, MA 01801, USA in
February, 2006. Test records are outlined in Chomerics Test Report #EMI4445.06. Further testing was
conducted by Chomerics Test Services, Woburn, MA. 01801, USA in November, 2008. Test records are
outlined in Chomerics Test report #EMI5193.08.
We hereby declare that the equipment specified conforms to the above Directives and Standards.

Carl Haapaoja, Director of Quality Assurance

Measurement Computing Corporation
10 Commerce Way
Suite 1008
Norton, Massachusetts 02766(508) 946-5100
Fax: (508) 946-9500
E-mail: info@mccdaq.com
www.mccdaq.com