WLS-TC
Wireless Thermocouple Measurement

User's Guide

Document Revision 4A
April 2014
© Copyright 2014

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.
© 2014 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 WLS-TC.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
Chapter 1

Introducing the WLS-TC ....................................................................................................................... 6
Overview: WLS-TC features .............................................................................................................................. 6
Remote wireless operation ................................................................................................................................................ 6

WLS-TC block diagram ..................................................................................................................................... 7
Chapter 2

Installing the WLS-TC ........................................................................................................................... 8
What comes with your WLS-TC shipment? ....................................................................................................... 8
Hardware .......................................................................................................................................................................... 8
Software ............................................................................................................................................................................ 8
Documentation .................................................................................................................................................................. 8

Unpacking........................................................................................................................................................... 8
Installing the software ........................................................................................................................................ 8
Installing the hardware ....................................................................................................................................... 8
Configuring the WLS-TC ................................................................................................................................... 9
Thermocouple type ........................................................................................................................................................... 9
Network parameters (remote operation) ..........................................................................................................................10

Connecting the external power supply for remote operation ............................................................................ 11
Calibrating the WLS-TC .................................................................................................................................. 11
Warm up time ................................................................................................................................................... 11
Chapter 3

Sensor Connections ...........................................................................................................................12
Screw terminal pinout ....................................................................................................................................... 12
Thermocouple inputs .......................................................................................................................................................12
CJC sensors......................................................................................................................................................................12
Digital I/O ........................................................................................................................................................................13
Power outputs ..................................................................................................................................................................13
Ground .............................................................................................................................................................................13

Thermocouple connections ............................................................................................................................... 13
Wiring configuration........................................................................................................................................................13

Digital I/O connections ..................................................................................................................................... 14
Configuring the DIO channels to generate alarms ...........................................................................................................14
Chapter 4

Functional Details ...............................................................................................................................15
Thermocouple measurements ........................................................................................................................... 15
Cold junction compensation (CJC) ..................................................................................................................................15
Data linearization .............................................................................................................................................................15
Open-thermocouple detection (OTD) ..............................................................................................................................15

AC power supply .............................................................................................................................................. 16External components ........................................................................................................................................ 16
Screw terminals................................................................................................................................................................16
Status LEDs .....................................................................................................................................................................17
LED Test button...............................................................................................................................................................17
USB connector .................................................................................................................................................................173

WLS-TC User's Guide

Chapter 5

Specifications ......................................................................................................................................18
Analog input ..................................................................................................................................................... 18
Channel configurations ..................................................................................................................................... 18
Accuracy ........................................................................................................................................................... 19
Thermocouple measurement accuracy .............................................................................................................................19

Throughput rate to PC (USB or wireless) ......................................................................................................... 19
Digital input/output........................................................................................................................................... 20
Temperature alarms .......................................................................................................................................... 20
Memory ............................................................................................................................................................ 20
Microcontroller ................................................................................................................................................. 21
Wireless communications ................................................................................................................................. 21
USB +5V voltage ............................................................................................................................................. 21
Power ................................................................................................................................................................ 22
USB specifications ........................................................................................................................................... 22
Environmental .................................................................................................................................................. 22
Mechanical ....................................................................................................................................................... 23
LED / button configuration ............................................................................................................................... 23
Screw terminal connector ................................................................................................................................. 24
Declaration of Conformity ..................................................................................................................25

4

Preface

About this User’s Guide
What you will learn from this user's guideThis user's guide describes the Measurement Computing WLS-TC 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 WLS-TC hardware is available on our website at www.mccdaq.com. You canalso contact Measurement Computing Corporation with specific questions.


Knowledgebase: kb.mccdaq.com
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

5Chapter 1

Introducing the WLS-TC
Overview: WLS-TC features
The WLS-TC is a wireless-based USB 2.0 full-speed thermocouple input module that is supported underpopular Microsoft® Windows® operating systems. The WLS-TC is fully compatible with both USB 1.1 andUSB 2.0 ports.
The WLS-TC provides eight differential thermocouple input channels. 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 software programmable for input or output.
With the WLS-TC, you can take measurements from type J, K, R, S, T, N, E, and B thermocouples.
The WLS-TC provides two integrated cold junction compensation (CJC) sensors for thermocouple
measurements.
An open thermocouple detection feature lets you detect a broken thermocouple. An onboard microprocessor
automatically linearizes the measurement data.
The WLS-TC 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.
All configurable options are software programmable. The WLS-TC is fully software-calibrated.
You can operate the WLS-TC as a standalone plug-and-play device which draws power through the USB cable.
You can also operate the WLS-TC as a remote device that communicates with the computer through the
WLS-IFC USB-to-wireless interface device. An external power supply is shipped with the device to provide
power during remote operations.

Remote wireless operation
When operating as a remote device, the WLS-TC communicates with the computer through the WLS-IFC
device connected to the computer's USB port.
Before you can operate the WLS-TC remotely, you must connect it to the computer's USB port and configure
the network parameters required to establish a wireless link with the interface device. Only devices with thesame parameter settings can communicate with each other. All configurable options are programmable with
InstaCal.
LEDs on the WLS-TC indicate the status of communication over the wireless link. An LED bar graph shows
the fade margin of signals received by the WLS-TC.
For more information on setting up network parameters, refer to "Network parameters (remote operation)" onpage 10.

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WLS-TC User's Guide

Introducing the WLS-TC

WLS-TC block diagram
WLS-TC functions are illustrated in the block diagram shown here.

Figure 1. WLS-TC functional block diagram

7

Chapter 2

Installing the WLS-TC
What comes with your WLS-TC shipment?
The following items are shipped with the WLS-TC.

Hardware

WLS-TCUSB cable
USB power adapter (2.5 watt AC-to-USB power adapter for remote wireless operation)

Software

MCC DAQ Software CD

Documentation

MCC DAQ Software Quick Start Guide
This booklet provides an overview of the MCC DAQ software you received with the device, and includes
information about installing the software. Please read this booklet completely before installing any softwareor hardware.
Setup Options
An overview of installation options is provided in the Wireless Setup document that ships with the device.

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.
If any components are missing or damaged, contact us immediately using one of the following methods:

Knowledgebase: kb.mccdaq.com
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
website at www.mccdaq.com/International.

Installing the software
Refer to the Quick Start Guide for instructions on installing the software on the MCC DAQ CD. This booklet isavailable in PDF at www.mccdaq.com/PDFmanuals/DAQ-Software-Quick-Start.pdf.

Installing the hardware
Before you operate the WLS-TC as a local or remote device, first install it onto your system and configure itwith InstaCal.
Install the MCC DAQ software before you install the WLS-TC
The driver needed to run your board is installed with the MCC DAQ software. Therefore, you need to install the
MCC DAQ software before you install your board. Refer to the Quick Start Guide for instructions on installingthe software.

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WLS-TC User's Guide

Installing the WLS-TC

Complete the following steps to connect the WLS-TC to your system:
1.

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 power and communication to the WLSTC.

Always connect an external hub to its power supply
If you are using a hybrid hub (one that can operate in either self-powered or bus-powered mode), always
connect it to its external power supply.
If you use a hub of this type without connecting to external power, communication errors may occur that could
result in corrupt configuration information on your wireless device. You can restore the factory default
configuration settings with InstaCal.
When you connect the WLS-TC for the first time, a notification message opens as the WLS-TC is detected.
After your system detects new hardware, the Found New Hardware Wizard opens and prompts you to
respond to the question "Can Windows connect to Windows Update to search for software?"2.

Click on the No, not this time option, and then click on the Next button.
The next dialog prompts you for the location of the software required to run the new hardware.

3.

Keep the default selection "Install the software automatically" and then click on the Next button.
The wizard locates and installs the software on your computer for the WLS-TC. A dialog appears when the
wizard completes the installation.

4.

Click on the Finish button to exit the wizard.

A dialog box opens when the hardware is installed and ready to use. The Command LED will blink and thenremain on to indicate that communication is established between the WLS-TC and your computer. The
Wireless Power LED turns on to indicate that the internal RF module is receiving power.

If the Command LED turns off
If the Command LED is on but then turns off, the computer has lost communication with the WLS-TC. If the
WLS-TC is connected to the computer USB port, disconnect the USB cable from the computer and thenreconnect it. This should restore communication, and the LED should turn back on.
If the Command LED turns off when you are operating the WLS-TC remotely through the wireless interface,disconnect the USB cable from the USB power adapter, and then reconnect it. This should restore
communication, and the Command LED should turn back on.

Configuring the WLS-TC
Before using the WLS-TC, configure the temperature sensors and network parameters for remote wirelesscommunication. All hardware configuration options on the WLS-TC are programmable with InstaCal.
Configuration options are stored on the WLS-TC in non-volatile memory in EEPROM, and are loaded on
power up.

Thermocouple typeUse InstaCal to set the thermocouple type for each channel. The factory default thermocouple configuration isType J. You can configure thermocouple settings when the WLS-TC is connected locally to the computer
through the USB port, or when the device is operated remotely through the wireless interface.
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WLS-TC User's Guide

Installing the WLS-TC

Network parameters (remote operation)
The following network parameter options are programmable with InstaCal.







Identifier: Text that identifies the device (optional).
PAN (hex): The personal area network (PAN) ID assigned to the device.

The PAN value is a number used to identify the interface device with which you want to communicate. The
WLS-TC can only communicate with a device whose PAN is set to the same value.
Most users do not need to change the default value assigned to the device. However, you may want toassign a different PAN ID in the following situations:o You have multiple WLS Series devices, and do not want to allow communication between all of them.
Set the PAN ID to the same value on each device that you want to communicate.
o If other WLS Series devices are operating in the vicinity, you can avoid accidental changes to yourdevice settings by changing the default PAN value.
CH: The radio frequency (RF) channel number assigned to the device.
The channel number is used to transmit and receive data over the wireless link. You may want to change
the channel number in InstaCal when another WLS Series device is already transmitting on that channel, or
when noise is present on the channel.
The table below lists each available channel and its corresponding transmission frequency.
RF
ChannelTransmission
Frequency (GHz)RF
ChannelTransmission
Frequency (GHz)

12
13
14
15
16
17

2.410
2.415
2.420
2.425
2.430
2.435

18
19
20
21
22
23

2.440
2.445
2.450
2.455
2.460
2.465

AES Key: Value used to encrypt data (optional).

AES encryption is disabled by default. Unless you suspect that there are other users of WLS Series devices
in the area, there should be no need to enable encryption. However, if you suspect that there are other WLS
Series devices in the area, and you need to secure the devices from being accessed by other users, enable
AES encryption.
Enabling encryption does NOT secure the device from access through a local USB connection. A remotedevice configured for encryption can be connected locally through the USB port to access other remote
WLS Series devices with the same settings; you may need to physically secure the remote devices toprevent tampering of the of device's network.
Set the PAN ID, RF channel, and AES key to the same value for each device that you want tocommunicate
Only devices with matching parameter settings for PAN, CH, and AES Key (if set) can communicate with eachother.
For information on setting up the network parameters for your WLS-TC, refer to the "WLS Series" section ofthe "Temperature Input Boards" chapter in the Universal Library Help.
After configuring the network parameters, disconnect the WLS-TC from the computer, and move the device toits remote location. The WLS-TC can be located up to 150 feet (50 meters) indoors, or up to ½ mile (750 m)
outdoors from the interface device.
Restoring factory default settings
You can restore the factory default configuration settings with InstaCal.

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WLS-TC User's Guide

Installing the WLS-TC

Connecting the external power supply for remote operation
Connect the USB cable to the AC-to-USB power adapter when you are operating the WLS-TC remotely
through the wireless interface. The Command and Wireless Power LEDs turn on approximately five seconds
after you connect the AC power adapter.
Caution! To satisfy FCC RF exposure requirements for mobile transmitting devices, maintain a separation
distance of 20 cm (0.66 feet) or more between the antenna of this device and personnel during
device operation. To ensure compliance, operation at closer than this distance is notrecommended. The antenna used for this transmitter must not be co-located in conjunction withany other antenna or transmitter.

Calibrating the WLS-TC
You can fully calibrate the WLS-TC using InstaCal. Allow a 30-minute warm up before calibrating. The normal
calibration interval is once per year.
You can calibrate the WLS-TC when it is connected locally to the computer through the USB port, or when it isoperating remotely through the wireless interface.

Warm up time
Allow the WLS-TC to warm up for 30 minutes before taking measurements. This warm up time minimizes
thermal drift and achieves the specified rated accuracy of measurements.

11

Chapter 3

Sensor Connections
The WLS-TC supports type J, K, R, S, T, N, E, and B thermocouples.
The thermocouple type you select depends on your application needs. Review the temperature ranges andaccuracies of each type to determine which is best suited for your application.

Screw terminal pinout
The WLS-TC has four banks of screw terminals. There are 26 connections on each side. Between each bank ofscrew terminals are two integrated CJC sensors used for thermocouple measurements. Signals are identified in
Figure 2.

Figure 2. WLS-TC screw terminal pin numbers

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

Thermocouple inputs
You can connect up to eight thermocouples to the differential sensor inputs (C0H/C0L to C7H/C7L). The
WLS-TC supports type J, K, R, S, T, N, E, and B thermocouples.

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

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WLS-TC User's Guide

Sensor Connections

Digital I/O
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.

Power outputs
The two +5V output terminals are isolated (500 VDC) from the USB +5V.

GroundThe 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
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 WLS-TC 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 which automatically detects an open or broken thermocouple is available
for each analog input.
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.

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

Figure 3. Typical thermocouple connection

Connect thermocouples to the WLS-TC so that they float with respect to GND (pins 9, 19, 28, 38). The WLSTC GND pins are isolated from earth ground, so you can connect thermocouple sensors to voltages referenced toearth ground as long as you maintain the isolation between the GND pins (9, 19, 28, 38) and earth ground.
When you attach thermocouples to conductive surfaces, the voltage differential between multiple
thermocouples must remain within ±1.4 V. For best results, use insulated or ungrounded thermocouples whenpossible.
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 the
WLS-TC is powered on, and ±40 VDC when the WLS-TC 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.

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WLS-TC 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. You can configure
each digital bit for either input or output. All digital I/O lines are pulled up to +5V with a 47 K ohm resistor(default). You can request the factory to configure the resistor for pull-down to ground if desired.
When you configure the digital bits for input, you can use the WLS-TC digital I/O terminals to detect the stateof any TTL-level input. Refer to the schematic shown in Figure 4. 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 4. Schematic showing switch detection by digital channel DIO0

Caution! All ground pins on the WLS-TC (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 WLS-TC features eight independent temperature alarms. All alarm options are software configurable.
Remote alarm configuration is supported.
When a digital bit is configured as an alarm, that bit is configured as an output on the next power cycle andassumes 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 also the output stateof 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 in wireless operations and while attached to the USB port on a computer.
You can configure alarm settings when you connect the WLS-TC locally to the computer through the USB port,
or when operating it remotely through the wireless interface.

14

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 WLS-TC 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 WLS-TC 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 WLSTC 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 WLS-TC subtracts the cold junction voltage from thethermocouple voltage.
The WLS-TC has two high-resolution temperature sensors that are integrated into the design of the WLS-TC.
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 onboard 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 WLS-TC is equipped with open-thermocouple detection for each analog input channel. The maximum open
detection time is 3 seconds.
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 to sample all channels when OTD is detected.
Input leakage current
With open-thermocouple detection enabled, a maximum of 105 nA 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

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WLS-TC User's Guide

Functional Details

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 OTD disabled, a maximum of 30 nA of input leakage current is
injected into the thermocouple.

AC power supply
The external power supply is an AC-to-USB 2.5 W supply that is used to power the WLS-TC during remotewireless operations (MCC p/n USB Power Adapter.)External components
The WLS-TC has the following external components, as shown in Figure 5.
Screw terminals
USB connector
Status LEDs (Command, Wireless Power, Transmit, Receive, Received Signal Strength indicators)
LED Test button

1
2
3
4
5

Screw terminal pins 1 to 26
Screw terminal pins 27 to 52
Command LED
LED Test button
Received Signal Strength (RSS) LEDs

6
7
8
9

Receive LED
Transmit LED
Wireless Power LED
USB connector

Figure 5. WLS-TC component locations

Screw terminals
The device's four banks of screw terminals are for connecting thermocouples and digital I/O lines. Theseterminals also provide ground and power output connections. Refer to the "Screw terminal pin out " section on
page 12 for screw terminal descriptions.
Caution! The two +5V terminals (pin 21 and pin 47) are isolated (500 VDC) from the USB +5V. Each +5V
terminal is an output. Do not connect to an external power supply or you may damage the WLSTC and possibly the computer.

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WLS-TC User's Guide

Functional Details

Status LEDs
The LEDs indicate the communication status of USB and wireless operations. In addition, three LEDs indicate
the signal strength of data transmitted over the wireless link. Refer to the table below for the function of eachLED.
LED functions
LED

Function

Command

Steady green – the WLS-TC is connected to a computer or AC adapter
Blinking green – the WLS-TC is receiving a command over the USB or wireless link.
The WLS-TC device's internal RF module is receiving power (USB or AC adapter)
Data is being transmitted over an active wireless link.
Data is being received over an active wireless link.
3 green LED bar graph. The LEDs will turn on when receiving a wireless message andstay on for approximately 1 second after the end of the message. They indicate theamount of fade margin present in an active wireless link. Fade margin is defined as thedifference between the incoming signal strength and the device’s receiver sensitivity.
 Three LEDs on: Very strong signal (> 30 dB fade margin)
 Two LEDs on: Strong signal (> 20 dB fade margin) One LED on: Moderate signal (> 10 dB fade margin)
 No LEDs on: Weak signal (< 10 dB fade margin)

Wireless Power (green)
Transmit (yellow)
Receive (red)Received Signal Strength(RSS) indicators LEDs

LED Test button
The LED test button tests the functionality of the LEDs. When pressed, each LED lights in sequence (first theCommand LED then left to right from the Wireless Power LED to the RSS indicator LEDs).

USB connector
The USB connector provides +5V power and communication. External power is required to operate the WLSTC remotely through the wireless interface.
For local operation, connect to the USB port or hub on your computer. For remote wireless operation, connect
to the AC-to-USB power adapter that shipped with the device.

17

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

Condition

Specification

Thermocouple

Four dual 24-bit, Sigma-Delta type
8 differential
500 VDC minimum between field wiring andUSB interface
Thermocouple sensor type±0.080 V

A/D converters
Number of channels
Input isolation
Channel configuration
Differential input voltage
range
Absolute maximum input
voltage
Input impedance
Input leakage current±C0x through ±C7x relative to GND(pins 9, 19, 28, 38)
Open thermocouple detect enabled

Normal mode rejection ratio
Common mode rejection ratio
Resolution
No missing codes
Input couplingWarm-up time
Open thermocouple detectfIN = 60 Hz
fIN = 50 Hz/60 Hz

CJC sensor accuracy

15 °C to 35 °C±25 V power on, ±40 V power off
5 GΩ, min
105 nA max
90 dB min
100 dB min
24 bits
24 bitsDC
30 minutes min
Automatically enabled when the channel pair isconfigured for thermocouple sensors.
The maximum open detection time is
3 seconds.
±0.25 °C typ±0.5 °C max–1.0 to +0.5 °C max

0 °C to 70 °C

Channel configurations
Table 2. Channel configuration specifications
Sensor Category

Condition

Specification

Thermocouple

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

8 differential channels

Note 1: Channel configuration information is stored in the EEPROM of the isolated microcontroller by thefirmware whenever any item is modified. Modification is performed by commands issued over USB or
wireless from an external application, and the configuration is made non-volatile through the use of the
EEPROM.
Note 2: The factory default configuration is Type J.

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Specifications

Accuracy
Thermocouple measurement accuracy
Table 3. Thermocouple accuracy specifications, including CJC measurement error
Sensor TypeMaximum error

Typical error

Temperature range

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

K
S
R
B
E
T
N

Note 3: Thermocouple specifications include linearization, cold-junction compensation and system noise.

These specs are for one year, or 3000 operating hours, whichever comes first and for operation of thedevice between 15 °C and 35 °C. For measurements outside this range, add ±0.5 degree 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 notinclude inherent thermocouple error. Please contact your thermocouple supplier for details on theactual thermocouple error.
Note 4: Thermocouples must be connected to the device such that they are floating with respect to GND (pins9, 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 is maintained.
Note 5: 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 ungrounded orinsulated thermocouples when possible.

Throughput rate to PC (USB or wireless)
Table 4. 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

Note 6: 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 thedevice is approximately 0.5 seconds.
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WLS-TC User's Guide

Specifications

Digital input/output
Table 5. 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 kΩ resistors (default). Pull down to ground (GND)
also available.
 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 7: All ground pins on the device (pins 9, 19, 28, 38) are isolated from earth ground. If a connection ismade to earth ground when using digital I/O and conductive thermocouples, the thermocouples are nolonger isolated. In this case, thermocouples must not be connected to any conductive surfaces that may
be referenced to earth ground.

Temperature alarms
Table 6. 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 will function both inwireless 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
Note: 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

Alarm input modes

Alarm output modes

Alarm update rate

MemoryTable 7. Memory specifications
Parameter

Specification

EEPROM

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

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WLS-TC User's Guide

Specifications

Microcontroller
Table 8. Microcontroller specifications
Parameter

Specification

Type

Three high performance 8-bit RISC microcontrollers

Wireless communications
Table 9. Wireless communications specifications
Parameter
Communication standard
Range
Transmit power output
Receiver sensitivity
RF channels
Addressing
Encryption

Specification
IEEE 802.15.4, ISM 2.4GHz frequency band, non-beacon, point-to-point
Indoor/urban: Up to 150 ft (50 m)
Outdoor RF line-of-sight: Up to ½ mile (750 m)
10 mW (10 dBm)
–100 dBm (1% packet error rate)
12 direct sequence channels available, channels 12 – 23 (2.410 – 2.465 GHz)
(software selectable)
16-bit PAN (personal area network) IDs per channel (software selectable)
64-bit device address
128-bit AES (software selectable)

Note 8: Contains FCC ID: OUR-XBEEPRO. The enclosed device complies with Part 15 of the FCC Rules.

Operation is subject to the following two conditions: (i.) this device may not cause harmfulinterference and (ii.) this device must accept any interference received, including interference that may
cause undesired operation.
Note 9: Canada: Contains Model XBee Radio, IC: 4214A-XBEEPRO
Caution! To satisfy FCC RF exposure requirements for mobile transmitting devices, a separation distanceof 20 cm or more should be maintained between the antenna of this device and persons during
device operation. To ensure compliance, operations at closer than this distance is notrecommended. The antenna used for this transmitter must not be co-located in conjunction withany other antenna or transmitter.

USB +5V voltage
Table 10. USB +5V voltage specifications
Parameter

Condition

Specification

USB +5V (VBUS) input voltage range

4.75 V min to 5.25 V max

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WLS-TC User's Guide

Specifications

Power
Table 11. Power specifications
Parameter

Condition

Specification

Connected to USB
Supply current
User +5V output voltage range(terminal block pin 21 and 47)
User +5V output current(terminal block pin 21 and pin 47)
Isolation

Connected to a self-powered hub. (Note 10)

500 mA max
4.75 V min to
5.25 V max
10 mA max

Measurement system to PC

500 VDC min

Connected to a self-powered hub. (Note 10)

Wireless Communications operation
Supply current

500 mA max

AC Adapter power supply (used for remote wireless communications operation)
Standalone power supply

USB power adapter
2.5 Watt USB adapter withinterchangeable plugs(Includes plug for USA)5V ±5%
2.5 W
100 – 240 VAC
50 – 60 Hz
0.2 A

Output voltage
Output wattage
Input voltage
Input current
Note 10:

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's USB Host Controller. The USB port(s) on your PC are root port
hubs. All externally powered root port hubs (desktop PC’s) 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 12. USB specifications
Parameter

Specification

USB device type
Device compatibility

USB 2.0 (full-speed)
USB 1.1, USB 2.0
Bus 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 meters max

USB cable type
USB cable length

Environmental
Table 13. Environmental specifications
Parameter

Specification

Operating temperature range
Storage temperature range
Humidity

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

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WLS-TC User's Guide

Specifications

Mechanical
Table 14. Mechanical specifications
Parameter

Specification

Dimensions (L × W × H)
USB cable length

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

LED / button configuration
Table 15. LED configuration
Parameter

Specification

Command LED

Green LED – indicates a command was received by the device (either USB or
wireless)Three green LED bar graph. The LEDs will turn on when receiving a wirelessmessage, and stay on for approximately 1 second after the end of the message.
These LEDs indicate the amount of fade margin present in an active wireless link.
Fade margin is defined as the difference between the incoming signal strength andthe device's receiver sensitivity.
 3 LEDs on: Very strong signal (> 30 dB fade margin) 2 LEDs on: Strong signal (> 20 dB fade margin) 1 LED on: Moderate signal (> 10 dB fade margin)
 0 LEDs on: Weak signal (< 10 dB fade margin)
Green LED: the internal RF module is receiving power.
Yellow LED: data is being transmitted over the wireless link.
Red LED: data is being received over the wireless link.
Firmware defined; this revision executes an LED test.

Received Signal Strength Indicator(RSSI) LEDs

Wireless Power LED
Transmit LED
Receive LED
ButtonCommand

Button(firmwaredefined)Transmit
Wireless Power

Receive

23

Received
SignalStrength

WLS-TC User's Guide

Specifications

Screw terminal connector
Table 16. Screw terminal connector specifications
Parameter

Specification

Connector type
Wire gauge range

Screw terminal
16 AWG to 30 AWG
Table 17. Screw terminal pinout

Pin
1
2
3
4
5
6

Signal Name
RSVD
NC
C0H
C0L
NC
RSVD

Pin Description
Reserved, do not use
No connection
CH0 sensor input (+)
CH0 sensor input (–)
No connection
Reserved, do not use

Pin
27
28
29
30
31
32

Signal Name
RSVD
GND
C7L
C7H
RSVD
NC

Pin Description
Reserved, do not use

7

C1H

CH1 sensor input (+)

33

C6L

CH6 sensor input (–)

8

C1L

C6H

CH6 sensor input (+)

9
10

GND
RSVD

CH1 sensor input (–)
GroundReserved, do not use

34
35
36

NC
RSVD

No connection
Reserved, do not use

CJC sensor

CH7 sensor input (–)
CH7 sensor input (+)
Reserved, do not use
No connection

CJC sensor

11
12

RSVD
NC

Reserved, do not use
No connection

37
38

RSVD
GND

Reserved, do not use
Ground13

C2H

CH2 sensor input (+)

39

C5L

CH5 sensor input (–)

14

C2L

C5H

CH5 sensor input (+)

15
16

NC
RSVD

CH2 sensor input (–)
No connection
Reserved, do not use

40
41
42

RSVD
NC

Reserved, do not use
No connection

17

C3H

CH3 sensor input (+)

43

C4L

CH4 sensor input (–)

18

C3L

44

C4H

CH4 sensor input (+)

19
20
21
22
23
24
25
26

GND
RSVD
+5V
GND
DIO0
DIO1
DIO2
DIO3

CH3 sensor input (–)
GroundReserved, do not use
Power output
GroundDIO channel 0
DIO channel 1
DIO channel 2
DIO channel 3

45
46
47
48
49
50
51
52

NC
RSVD
+5V
GND
DIO7
DIO6
DIO5
DIO4

No connection
Reserved, do not use
Power output
GroundDIO channel 7
DIO channel 6
DIO channel 5
DIO channel 424

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 product

WLS-TC
to which this declaration relates is in conformity with the relevant provisions of the following standards or otherdocuments:
EU EMC Directive 89/336/EEC: Electromagnetic Compatibility, EN 61326 (1997) Amendment 1 (1998)
Emissions: Group 1, Class B
EN 55011 (1990)/CISPR 11: Radiated and Conducted emissions.

Immunity: EN61326, Annex AIEC 61000-4-2 (1995): Electrostatic Discharge immunity, Criteria C.
IEC 61000-4-3 (1995): Radiated Electromagnetic Field immunity Criteria A.
IEC 61000-4-8 (1994): Power Frequency Magnetic Field immunity Criteria A.

ETSI EN301 489-1 (2004)
IEC 61000-3-2 (2001) Harmonic Current Emissions, IEC 61000-3-3 (2003) Voltage Fluctuations and Flicker
Emissions: Group 1, Class B

CISPR 22 (2004): Radiated and Conducted Electromagnetic Emissions (USB cable with ferrite suppressor
assembly required).
IEC 61000-3-2 (2001): Harmonic Emissions Class A
IEC 61000-3-3 (2003): Fluctuations and Flicker

Immunity:







IEC 61000-4-2 (2001): Electrostatic Discharge immunity, Criteria C.
IEC 61000-4-3 (2002): Radiated Electromagnetic Field immunity Criteria A.
IEC 61000-4-4 (2004): Electric fast transient burst immunity Criteria B.
IEC 61000-4-5: Fast surge immunity Criteria B
IEC 61000-4-6 (2003): Radio Frequency Common Mode immunity Criteria B*.
IEC 61000-4-11 (2004): Voltage dips and interrupt immunity Criteria B* There may be a loss of performance in the presence of an RF electromagnetic disturbance on the input/output
ports. Performance loss will be limited to measured temperatures outside of specified accuracy. The transmitter/ receiver will continue to operate as specified. Stored data and operating state will be maintained during the
disturbance. Operation will recover to within specified limits after the disturbance is removed.
Declaration of Conformity based on tests conducted by Chomerics Test Services, Woburn, MA 01801, USA in
November, 2006. Test records are outlined in Chomerics Test Report #EMI4660.06.
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