USB-2404-UI
USB-based Universal Analog Input Device

User's Guide

Document Revision 2A
March 2012
© Copyright 2012

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.
© 2012 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-2404-UI.docx

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
Hazardous voltages ............................................................................................................................................. 5
Hazardous locations ............................................................................................................................................ 5
Chapter 1

Introducing the USB-2404-UI ............................................................................................................... 6
Overview: USB-2404-UI features ...................................................................................................................... 6
Functional block diagram ................................................................................................................................... 7
Chapter 2

Installing the USB-2404-UI ................................................................................................................... 8
What comes with your USB-2404-UI shipment? ............................................................................................... 8
Hardware .......................................................................................................................................................................... 8
Documentation .................................................................................................................................................................. 8

Unpacking........................................................................................................................................................... 8
Installing the software ........................................................................................................................................ 8
Installing the hardware ....................................................................................................................................... 8
Calibrating the USB-2404-UI ............................................................................................................................. 9
Chapter 3

Functional Details ............................................................................................................................... 10
Components ...................................................................................................................................................... 10
Spring terminal connectors ..............................................................................................................................................10
Strain relief slot................................................................................................................................................................11
USB connector .................................................................................................................................................................11
LED .................................................................................................................................................................................11

Connecting wires to the spring terminals ......................................................................................................... 11
TEDS sensor connections ................................................................................................................................................12Signal source connections ................................................................................................................................................12

Timing options.................................................................................................................................................. 12
USB-2404-UI circuitry ..................................................................................................................................... 13
Analog input circuitry ......................................................................................................................................................13
Voltage and current modes ..............................................................................................................................................13
4-wire resistance and 4-wire RTD modes ........................................................................................................................13
3-wire RTD mode ............................................................................................................................................................14
2-wire resistance and quarter-bridge modes .....................................................................................................................14
Half-bridge and full-bridge modes ...................................................................................................................................14
Thermocouple mode ........................................................................................................................................................15
Excitation protection ........................................................................................................................................................15
Chapter 4

Specifications ...................................................................................................................................... 16
Analog input ..................................................................................................................................................... 16
Input mode ranges ............................................................................................................................................................16
Accuracy ..........................................................................................................................................................................17
Stability............................................................................................................................................................................17
Input noise .......................................................................................................................................................................18
Excitation level ................................................................................................................................................................18

Power ................................................................................................................................................................ 18
Bus interface ..................................................................................................................................................... 193

USB-2404-UI User's Guide

Environmental .................................................................................................................................................. 19
Mechanical ....................................................................................................................................................... 19
Safety voltages .................................................................................................................................................. 19
Spring terminal connectors ............................................................................................................................... 19
Accessory products ........................................................................................................................................... 20
Declaration of Conformity .................................................................................................................. 21

4

Preface

About this User's Guide
What you will learn from this user's guideThis user's guide describes the Measurement Computing USB-2404-UI data acquisition device and lists device
specifications.

Conventions in this user's guide
For more information about …
Text presented in a box signifies additional information and helpful hints related to the subject matter you arereading.
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-2404-UI hardware is available on our website at www.mccdaq.com. You
can also contact Measurement Computing Corporation by phone, fax, or email with specific questions.
Phone: 508-946-5100 and follow the instructions for reaching Tech Support.
Fax: 508-946-9500 to the attention of Tech Support
Email: techsupport@mccdaq.com

Hazardous voltages
You can connect hazardous voltages to the USB-2404-UI device's spring terminals. A hazardous voltage is a
voltage greater than 42.4 Vpk or 60 VDC to earth ground. Take the following precautions if you connect
hazardous voltages to the USB-2404-UI:
Caution! Ensure that hazardous voltage wiring is performed only by qualified personnel adhering to local
electrical standards.
Do not mix hazardous voltage circuits and human-accessible circuits on the same device.
Make sure that devices and circuits connected to the USB-2404-UI are properly insulated fromhuman contact.
When device terminals are hazardous voltage LIVE (>42.4Vpk/60 VDC), ensure that devices andcircuits connected to the USB-2404-UI are properly insulated from human contact. A high voltage
screw terminal backshell (ACC-176) must be installed when using hazardous voltages to ensurethat the terminals are not accessible.

Hazardous locations
The USB-2404-UI is not certified for use in hazardous locations.

5Chapter 1

Introducing the USB-2404-UI
Overview: USB-2404-UI features
This user's guide contains all of the information you need to connect the USB-2404-UI to your computer and to
the signals you want to measure.
The USB-2404-UI is a USB 2.0 high-speed device that is supported under popular Microsoft® Windows®
operating systems. The USB-2404-UI is fully compatible with both USB 1.1 and USB 2.0 ports.
The USB-2404-UI provides four channels of 24-bit universal analog input with integrated signal conditioning.
The device can be used to measure several signals from sensors such as RTDs, thermocouples, load cells, andother powered sensors. The four channels are individually configurable, so a different measurement type can be
performed on each channel. All channels are measured simultaneously at up to 100 S/s per channel.
The USB-2404-UI can perform the following measurements:







Voltage
Current
Thermocouple
RTD (4-wire and 3-wire)
Resistance (4-wire and 2-wire)
Bridge-based sensors (quarter-, half-, and full-bridge)

Measurement ranges vary for each type of measurement.
The device features built-in current and voltage excitation. The excitation circuit is protected from overcurrent
and overvoltage fault conditions. Each channel also has a built-in thermistor for cold-junction compensation(CJC) calculations when measuring thermocouples.
An analog pre-filter removes noise that may be present in the signals prior to conversion. With 250 VAC
channel-to-channel and channel-to-ground isolation, the USB-2404-UI protects the individual channels andconnected computer from ground spikes, and ensures a reliable data stream. An on-board LED indicates thestatus of the device.
Each channel has a detachable six-position spring terminal for field wiring connections. Additional connectors
are available for purchase. A strain relief kit is also available to secure signal wires.
The USB 2.0 high-speed driver transfers data at rates up to 480 Mbps. The USB-2404-UI is powered by the+5 volt USB supply from your computer. No external power is required.

6

USB-2404-UI User's Guide

Introducing the USB-2404-UI

Functional block diagram
USB-2404-UI functions are illustrated in the block diagram shown here.

Figure 1. USB-2404-UI functional block diagram

7

Chapter 2

Installing the USB-2404-UI
What comes with your USB-2404-UI shipment?
As you unpack your USB-2404-UI, verify that the following components are included.

Hardware

USB-2404-UI
USB cable (2 meter length)

Documentation
In addition to this hardware user's guide, a Quick Start Guide booklet is included with the USB-2404-UI
shipment. This booklet provides an overview of the MCC DAQ software you received with the device, andincludes information about installing the software. Please read this booklet completely before installing any
software or hardware.
Optional accessories

ACC-164 — Six-position screw terminal connector blocks (quantity four).
ACC-176 — Backshell for use with the ACC-164 six-position spring terminal connector blocks. Provides
strain relief and operator protection from high-voltage signals (quantity four).

UnpackingAs with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the USB-2404-UI from its packaging, ground yourself using a wrist strap or bysimply touching the computer chassis or other grounded object to eliminate any stored static charge.
If your USB-2404-UI is damaged, notify Measurement Computing Corporation immediately by phone, fax, ore-mail.


Phone: 508-946-5100 and follow the instructions for reaching Tech Support.
Fax: 508-946-9500 to the attention of Tech Support
Email: techsupport@mccdaq.com

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

Installing the software
Install Universal Library and InstaCal when you want to develop data acquisition applications using Windows
programming languages.
Universal Library and InstaCal software are included on the CD that ships with the device. Refer to the Quick
Start Guide booklet for instructions about installing Universal Library and InstaCal software.

Installing the hardware
Install the software before you install your device
A driver needed to run the USB-2404-UI device is installed when you install the software. Therefore, you needto install the software package you plan to use before you install the hardware.
For operation on a Windows operating system, we recommend that you run Windows Update to update youroperating system with the latest USB drivers.

8

USB-2404-UI User's Guide

Installing the USB-2404-UI

Be sure you are using the latest system software
Before you install your USB-2404-UI, run Windows Update to update your operating system with the latest
USB drivers.
To connect the USB-2404-UI to your system, turn your computer on, and connect the USB cable to a USB port
on your computer or to an external USB hub that is connected to your computer. The USB cable provides powerand communication to the USB-2404-UI.
USB 2.0 port or hub recommended
For optimum performance, connect the USB-2404-UI to a USB 2.0 Hi-Speed host controller (480 Mbps) andUSB 2.0 high-speed hub. The USB-2404-UI can be connected to a USB 1.1 Full-Speed port or hub, although
performance may be affected.
To connect a USB-2404-UI device to your system, turn on your computer and connect the USB cable to anavailable USB port on the computer or to an external USB hub connected to the computer. Connect the otherend of the USB cable to the USB connector on the device. No external power is required.
When you connect the device for the first time to a computer running Windows, a Found New Hardware dialog
opens when the operating system detects the device. The dialog closes after the device is installed.
The green LED on the USB-2404-UI blinks steadily to indicate that the device is initialized and receiving
power.
Allow the USB-2404-UI to operate for at least 30 minutes before using the device. This warm up time isrequired to achieve the specified rated accuracy of measurements.
Caution! Do not disconnect any device from the USB bus while the computer is communicating with theUSB-2404-UI, or you may lose data and/or your ability to communicate with the device.
If the LED is off
If the LED is on but then turns off, the computer has lost communication with the USB-2404-UI device. To
restore communication, disconnect the USB cable from the computer and then reconnect it. This should restore
communication, and the LED should turn on.

Calibrating the USB-2404-UIThe USB-2404-UI is shipped fully calibrated. Calibration coefficients are stored in EEPROM. Return thedevice to Measurement Computing Corporation when calibration is required. The normal calibration interval isonce per year.

9Chapter 3

Functional Details
Components
The USB-2404-UI has the following external components:

Spring terminal connectors
Strain relief slot for USB cable
USB connector
LED

Figure 2. Front panel

Figure 3. Rear panel

Spring terminal connectors
The USB-2404-UI has four 6-terminal connectors (CH0 to CH3) that provide connections for four analog input
channels. The signal names for the spring terminal in each connector are listed in the table below.
6-terminal connector signal names
Terminal
numberSignal
name

Signal description

1
2
3*
4
5*
6

T+
T–
EX+/HI
HI
EX–/LOLOTEDS Data
TEDS Common
Positive excitation or input signal
Positive input signal
Negative excitation or input signal
Negative input signal* Depending on the input mode, terminals 3 and 5 are either excitation signals or input signals.
10USB-2404-UI User's Guide

Functional Details

Connect the positive signal of the signal source to the positive input signal terminal (HI).
Connect the negative signal of the signal source to the negative input signal terminal (LO).
Connect to the excitation terminals (EX+/EX–)-if the sensor requires a separate excitation connection.

The spring terminal assignments for each input mode are listed in the following table.
6-position spring terminal assignments per input mode
Terminal
3456BridgeVoltageTC

Current

—
HI
LO
—

HI
—
LO
—

Full

Half

Quarter

EX+
HI
EX–
LO

EX+
HI
EX–
LO

HI
—
LO
—

Resistance

RTD

2-wire4-wire4-wire
EX+
HI
EX–
LO

3-wire
EX+
—
EX–
LO

Refer to "USB-2404-UI circuitry" on page 13 for information about connections in each mode.

Strain relief slot
Use the strain relief slot to keep the USB cable from disconnecting from the device inadvertently. Feed a tie
wrap through the slot and secure to the USB cable when it is connected to the device.

USB connector
The USB connector provides +5 V power and communication. The voltage supplied through the USB connector
is system-dependent, and may be less than 5 V. No external power supply is required.

LED
The LED indicates the device status. When connected to a USB port, the LED blinks steadily to indicate thatthe device is initialized and receiving power. Refer to the following table for the possible LED states.
LED state/device status
LED state

Device status

Not litContinuous single-blink
Continuous double-blink

The device is not connected to a USB port or hub.
The device is operating normally.
The device is operating normally. (Connected to a USB 1.1 port or hub.)Connecting wires to the spring terminals
Use a flathead screwdriver with a blade smaller than 2.3 x 1.0 mm (0.09 x 0.04 in.) to connect wires to thedetachable spring terminal connectors. Use 18 to 28 AWG copper conductor wire with 7 mm (0.28 in.) of
insulation stripped from the end when wiring connections.
Insert the screwdriver into the spring clamp activation slot and press a wire into the corresponding connector
terminal, then remove the screwdriver to clamp the wire into the terminal.

Figure 4. Connecting a wire to the spring terminal connector

11USB-2404-UI User's Guide

Functional Details

TEDS sensor connections
The USB-2404-UI supports class II TEDS "smart" sensors only. Connect the two TEDS lines to TEDS Data
(T+) and TEDS Common (T–), and ensure that neither T+ nor T– is tied in common to any of the signal inputs(terminals 3 through 6).

Signal source connections
You can connect ground-referenced or floating signal sources to the USB-2404-UI. For optimum signal quality,
use shielded cables and twisted pair wiring whenever possible.
When making a floating connection between the signal source and the USB-2404-UI, make sure the voltages on
the positive and negative connections are within the channel-to-earth voltage range. Refer to the Specifications
chapter for operating voltages and information about overvoltage protection.

Figure 5. Connecting a grounded signal source

Figure 6. Connecting a floating signal source

Don't connect to signals or use for measurements within category III or IV
Refer to the "Safety voltages" section in the Specifications chapter for information about Measurement
Categories.

Timing options
The USB-2404-UI supports four timing options. Each option is optimized for different types of applications byusing different ADC conversion times.
High Speed: optimized for high-speed applications at the expense of noise rejection.
Best 60 Hz Rejection: optimized for rejection of 60 Hz noise.
Best 50 Hz Rejection: optimized for rejection of 50 Hz noise.
High Resolution: optimized for maximum overall noise rejection, and provides a good rejection of both

50 Hz and 60 Hz noise.
Refer to the analog input specifications for the conversion time and rejection ratio of each option.

12

USB-2404-UI User's Guide

Functional Details

USB-2404-UI circuitry
Analog input circuitry
The USB-2404-UI is channel-to-channel isolated. Four 24-bit analog-to-digital converters (ADCs)
simultaneously sample all four analog input channels. An excitation circuit is enabled for all input modes that
require excitation. The ADC and excitation circuits are reconfigured in each mode to accommodate each sensor
type. Figure 7 shows the input circuitry for one channel.

Figure 7. Input circuitry for one channel

Voltage and current modes
In voltage and current modes, connect the signal source to the USB-2404-UI across the HI and LO terminals.
The current is computed from the voltage that the ADC measures across an internal shunt resistor. Voltage andcurrent mode connections are shown in Figure 8.

Figure 8. Voltage and current mode connections

4-wire resistance and 4-wire RTD modes
4-wire resistance and 4-wire RTD modes source a current which varies based on the resistance of the load
between the EX+ and EX– terminals. The measured resistance is calculated from the resulting voltage reading.
These modes are not affected by lead wire resistance, because a negligible amount of current flows across the
HI and LO terminals due to the high impedance of the ADC. 4-wire resistance and 4-wire RTD modeconnections are shown in Figure 9.

Figure 9. 4-wire resistance and 4-wire RTD mode connections

13

USB-2404-UI User's Guide

Functional Details

3-wire RTD mode
3-wire RTD mode sources a current which varies based on the resistance of the load between the EX+ and
EX– terminals. This mode compensates for lead wire resistance in hardware if all lead wires have the same
resistance. A gain of 2x is applied to the voltage across the negative lead wire. The ADC uses this voltage as thenegative reference to cancel the resistance error across the positive lead wire. 3-wire RTD mode connections areshown in Figure 10.

Figure 10. 3-wire RTD mode connections

2-wire resistance and quarter-bridge modes
In 2-wire resistance and quarter-bridge modes, connect the two ends of the resistor or gauge to the USB-2404UI across the HI and LO terminals. These modes source a current which varies based on the resistance of theload between the HI and LO terminals. The resulting resistance is calculated from the voltage measurement.
2-wire and quarter-bridge modes do not compensate for lead wire resistance. 2-wire resistance andquarter-bridge mode connections are shown in Figure 11.

Figure 11. 2-wire resistance and quarter-bridge mode connections

Half-bridge and full-bridge modes
Half-bridge and full-bridge modes use the internal voltage excitation to set the input range of the ADC, andreturn voltage readings that are proportional to the excitation level. The internal excitation voltage is nominally
2.5 V, but it can vary based on the resistance of the sensor. Refer to the Specifications chapter for more
information about excitation levels.
In half-bridge mode, the HI input is referenced to EX–. In full-bridge mode, the ADC reads the HI and LO
inputs differentially.
Half-bridge and full-bridge mode connections are shown in Figure 12. The dotted lines in the figure represent
the portion of the circuit that is only connected in full-bridge mode.

14

USB-2404-UI User's Guide

Functional Details

Figure 12. Half-bridge and full-bridge mode connections

Thermocouple mode
In thermocouple mode, connect the positive end of the thermocouple to HI, and the negative end of thethermocouple to LO. This mode uses the ±1.25 mV range of the ADC to return a voltage reading. Use shieldedcables and twisted pair wiring, and ground the shielded cables.
Each channel has a built-in thermistor for cold-junction compensation (CJC) calculations. For improved CJC
sensor accuracy, operate the USB-2404-UI in a stable temperature environment, and avoid placing heat sources
near the device or its connectors. Open thermocouple detection is not supported. Refer to the Specifications
chapter for more information about accuracy. Thermocouple mode connections are shown in Figure 13.

Figure 13. Thermocouple mode connections

Excitation protection
The USB-2404-UI excitation circuit is protected from overcurrent and overvoltage fault conditions. The circuit
is automatically disabled in the event of a fault condition. Whenever possible, channels automatically recoverafter the fault is removed.

15

Chapter 4

Specifications
All specifications are subject to change without notice.
Typical for the range 0 to 60 °C unless otherwise noted.

Analog input
Table 1. Analog input specifications
Parameter

Conditions

Specification

Number of channels

4

A/D converter resolution

24-bitA/D converter type

Delta-Sigma with analog pre-filtering

Sampling mode

Simultaneous

TEDS sensor type supported

IEEE 1451.4 TEDS Class II (interface) Voltage Current Resistance (4-wire and 2-wire) RTD (3-wire and 4-wire) Thermocouple
 Quarter-bridge
 Half-bridge
 Full-bridge
10 ms for all channels
110 ms for all channels
130 ms for all channels
500 ms for all channels
20 ms for all channels
120 ms for all channels
140 ms for all channels
510 ms for all channels
±30 V
±60 V

Input mode

Conversion time
(No channels in TC mode)

Conversion time
(One or more channels in TC mode)

Overvoltage protection

Input impedance

Input bias current
Integral non-linearity (INL)
Common mode rejection ratio(CMRR)
Normal mode rejection ratio(NMRR)High speed
Best 60 Hz rejection
Best 50 Hz rejection
High resolution
High speed
Best 60 Hz rejection
Best 50 Hz rejection
High resolution
Terminals 1 and 2
Terminals 3 through 6, across any
combination
Voltage mode(±60 V, ±15 V, ±4 V)
Current mode
All other modes

1 MΩ
<40 Ω
>1 GΩ
<1 nA
±15 ppm>100 dB

Best 60 Hz rejection
Best 50 Hz rejection
High resolution

90 dB at 60 Hz
80 dB at 50 Hz
65 dB at 50 Hz and 60 Hz

Input mode ranges
Table 2. Input mode range specifications
Input mode

Nominal range(s)Actual range(s)Voltage±60 V, ±15 V, ±4 V, ±1 V, ±125 mV±60 V, ±15 V, ±4 V, ±1 V, ±125 mV

16

USB-2404-UI User's Guide

Current
4-wire and 2-wire resistance
Thermocouple
4-wire and 3-wire RTD
Quarter-bridge
Half-bridge
Full-bridge

Specifications±25 mA
10 kΩ, 1 kΩ
±125 mV
Pt 1000, Pt 100
350 Ω, 120 Ω±500 mV/V±62.5 mV/V, ±7.8 mV/V

±25 mA
10.5 kΩ, 1.05 kΩ±125 mV
5.05 kΩ, 505 Ω
390 Ω, 150 Ω±500 mV/V±62.5 mV/V, ±7.8125 mV/V

Accuracy
Table 3. Accuracy specifications
Gain error (percent of reading)

Offset error (ppm of range)

Mode, range

Typical 25 ºC, ±5 ºC, –40 to 70 ºC maximum

Voltage, ±60 V
Voltage, ±15 V
Voltage, ±4 V
Voltage, ±1 V
Voltage/Thermocouple, ±125 mV
Current, ±25 mA
4-wire and 2-wire (note 1) resistance,
10 kΩ
4-wire and 2-wire (note 1) resistance,
1 kΩ
4-wire and 3-wire RTD, Pt 1000
4-wire and 3-wire RTD, Pt 100
Quarter-bridge, 350 Ω
Quarter-bridge, 120 Ω
Half-bridge, ±500 mV/V
Full-bridge, ±62.5 mV/V
Full-bridge, ±7.8 mV/V
Cold-junction compensation sensor
accuracy±0.3, ±0.4
±0.3, ±0.4
±0.3, ±0.4±0.1, ±0.18±0.1, ±0.18±0.1, ±0.6
±0.1, ±0.5±20, ±50±60, ±180±240, ±720
±15, ±45±120, ±360
±30, ±100±120, ±320±0.1, ±0.5±1200, ±3200±0.1, ±0.5±0.1, ±0.5±0.1, ±0.5±0.1, ±0.5
±0.03, ±0.07±0.03, ±0.08±0.03, ±0.08±240, ±640
±2400, ±6400±2400, ±6400±2400, ±6400±300, ±450
±300, ±1000±2200, ±8000±1 ºC, typical

Note 1: 2-wire resistance mode accuracy depends on the lead wire resistance. This table assumes 0 Ω of leadwire resistance.

Stability
Table 4. Stability specifications
Measurement conditions

Gain drift (ppm of reading/ ºC)

Offset drift (ppm of range/ ºC)

Voltage, ±60 V
Voltage, ±15 V
Voltage, ±4 V
Voltage, ±1 V
Voltage/thermocouple, ±125 mV
Current, ±25 mA
4-wire and 2-wire resistance, 10 kΩ
4-wire and 2-wire resistance, 1 kΩ
4-wire and 3-wire RTD, Pt 1000
4-wire and 3-wire RTD, Pt 100
Quarter-bridge, 350 Ω
Quarter-bridge, 120 Ω
Half-bridge, ±500 mV/V

±20
±20
±20
±10
±10
±15
±15
±15
±15
±15
±15
±15
±3

±0.2
±0.8
±3.2
±0.2
±1.6
±0.4
±3
±30
±6
±60
±120
±240
±20

17

USB-2404-UI User's Guide

Specifications

Full-bridge, ±62.5 mV/V
Full-bridge, ±7.8 mV/V

±3
±3

±20
±20

Input noise
Table 5. Input noise (ppm of rangerms) specifications
Conversion timeHigh speed

Best of 60 Hz
rejection

Best of 50 Hz
rejection

High resolution

7.6
10.8
10.8
7.6
10.8
10.8
4.1
7.1
7.6
10.8
5.4
5.4
3.8
5.4
30

1.3
1.9
2.7
1.3
1.9
1.9
1.3
1.8
1.7
1.9
1.0
1.0
0.5
1.0
4.7

1.3
1.9
2.7
1.3
1.9
1.9
0.8
1.2
1.1
1.9
1.0
1.0
0.5
1.0
4.7

0.5
0.7
1.3
0.5
1.0
1.0
0.3
0.7
0.4
0.9
0.7
0.7
0.2
0.8
2.3

Mode, range
Voltage, ±60 V
Voltage, ±15 V
Voltage, ±4 V
Voltage, ±1 V
Voltage/Thermocouple, ±125 mV
Current, ±25 mA
4-wire and 2-wire resistance, 10 kΩ
4-wire and 2-wire resistance, 1 kΩ
4-wire and 3-wire RTD, Pt 1000
4-wire and 3-wire RTD, Pt 100
Quarter-bridge, 350 Ω
Quarter-bridge, 120 Ω
Half-bridge, ±500 mV/V
Full-bridge, ±62.5 mV/V
Full-bridge, ±7.8 mV/V

Excitation level
Table 6. Half-bridge and full-bridge mode excitation level specifications
Measurement conditions

Load resistance (Ω)

Excitation (V)Half-bridge
Half-bridge
Full-bridge
Full-bridge

700
240
350
120

2.5
2.0
2.7
2.2

Table 7. Resistance, RTD, and quarter-bridge mode excitation level specifications
Load resistance (Ω)

Excitation (mV)

120
350
1,000
10,000

50
150
430
2,200

Power
Table 8. Power specifications
Parameter

Specification

Current consumption from USB

500 mA, maximum18USB-2404-UI User's Guide

Specifications

Bus interface
Table 9. Bus interface specifications
Parameter

Specification

USB specification

USB 2.0 Hi-Speed

Environmental
Table 10. Environmental specifications
Parameter

Specification

Operating temperature range
Storage temperature range
Operating humidity
Storage humidity
Maximum altitude

0 to 60 ºC–40 to 85 ºC
10 to 90% RH, non-condensing
5 to 95% RH, non-condensing
2000 meter (6562 feet)

Note 2: The USB-2404-UI is intended for indoor use only, but may be used outdoors if installed in a suitableenclosure

Mechanical
Table 11. Mechanical specifications
Parameter

Specification

Dimensions
Weight5.27" (L) x 5.64" (W) x 1.54" (H) (134 mm x 143 mm x 39 mm)
1.25 lbs (567 grams)

Safety voltages
Connect only voltages that are within the limits specified in this table.
Table 12. Safety specifications
Parameter

Conditions

Specification

Channel-to-earth ground isolation

Continuous
WithstandContinuous
Withstand

250 VAC, Measurement Category II (Note 3)
2300 VAC, verified by a 5 second dielectric withstand test
250 VAC, Measurement Category II (Note 3)1390 VAC, verified by a 5 second dielectric withstand test

Channel-to-channel isolation

Note 3: Measurement Category II is for measurements performed on circuits directly connected to theelectrical distribution system. This category refers to local-level electrical distribution, such as thatprovided by a standard wall outlet, for example 115 V for US or 230 V for Europe.
Caution! Do not connect the device to signals or use for measurements within Measurement Categories
III or IV.

Spring terminal connectors
Table 13. Spring terminal specifications
Connector type
Spring terminal wiring

Four 6-position spring terminal connectors
18 to 28 AWG copper conductor wire with 7 mm (0.28 in.) of insulation stripped from the
end.

19

USB-2404-UI User's Guide

Specifications

Table 14. Signal names
Terminal number

Signal nameSignal description

1
2
3
4
5
6

T+
T–
EX+/HI (Note 4)
HI
EX–/LO (Note 4)
LO

TEDS Data
TEDS Common
Positive excitation or input signal
Positive input signal
Negative excitation or input signal
Negative input signal

Note 4: Depending on the input mode, terminals 3 and 5 are either excitation signals or input signals.
Table 15. Terminal assignments per input mode
Input mode

Signal terminals
1

2

3

4

5

6

Voltage
Current
4-wire resistance
2-wire resistance
Thermocouple
4-wire RTD
3-wire RTD
Quarter-bridge
Half-bridge
Full-bridge

T+
T+
T+
T+
T+
T+
T+
T+
T+
T+

T–
T–
T–
T–
T–
T–
T–
T–
T–
T–

—
HI
EX+
HI
—
EX+
EX+
HI
EX+
EX+

HI
—
HI
—
HI
HI
—
—
HI
HI

LO
LO
EX–
LO
LO
EX–
EX–
LO
EX–
EX–

—
—
LO
—
—
LO
LO
—
—
LO

Accessory products
Table 16. Accessory products
ACC-164
ACC-176

6-position spring terminal connector block (quantity four)
Backshell for use with the ACC-164 6-position spring terminal connector blocks. Provides
strain relief and operator protection from high-voltage signals (quantity four).

20

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-2404-UI
to which this declaration relates is in conformity with the relevant provisions of the following standards or otherdocuments:
EC EMC Directive 2004/108/EC: General Requirements, EN 61326-1:2006 (IEC 61326-1:2005).
Emissions:EN 55011 (2007) / CISPR 11(2003): Radiated emissions: Group 1, Class B
EN 55011 (2007) / CISPR 11(2003): Conducted emissions: Group 1, Class B

Immunity: EN 61326-1:2006, Table 3.


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

To maintain compliance to the standards of this declaration, the following conditions must be met.







The host computer, peripheral equipment, power sources, and expansion hardware must be CE compliant.
All I/O cables must be shielded, with the shields connected to ground.
I/O cables 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.
Equipment must be operated in a controlled electromagnetic environment as defined by Standards EN
61326-1:2006, or IEC 61326-1:2005.

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
April, 2009. Test records are outlined in Chomerics Test Report #EMI5285.09.
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