Page 1
omega.com
e-mail: [email protected]
For latest product manuals:
omegamanual.info
OM-USB-TEMP
8 Channel
Temperature Measurement
USB Data Acquisition Module
Shop online at
User’s Guide
Extended Warranty
Program
SM
Page 2
Servicing North America:
U.S.A.: Omega Engineering, Inc., One Omega Drive, P.O. Box 4047
ISO 9001 Certified Stamford, CT 06907-0047 USA
Canada: 976 Bergar
Laval (Quebec), H7L 5A1 Canada
Toll-Free: 1-800-826-6342 TEL: (514) 856-6928
FAX: (514) 856-6886 e-mail: [email protected]
For immediate technical or application assistance:
U.S.A. and Canada: Sales Service: 1-800-826-6342/1-800-TC-OMEGA
®
Customer Service: 1-800-622-2378/1-800-622-BEST
®
Engineering Service: 1-800-872-9436/1-800-USA-WHEN
®
Mexico/ En Español: 001 (203) 359-7803 FAX: 001 (203) 359-7807
Latin America: [email protected] e-mail: [email protected]
Servicing Europe:
Benelux: Managed by the United Kingdom Office
Czech Republic: Frystatska 184
733 01 Karviná, Czech Republic
Toll-Free: 0800-1-66342 TEL: +420-59-6311899
FAX: +420-59-6311114 e-mail: [email protected]
France: Managed by the United Kingdom Office
Toll-Free: 0800 466 342 TEL: +33 (0) 161 37 29 00
FAX: +33 (0) 130 57 54 27 e-mail: [email protected]
Germany/Austria: Daimlerstrasse 26
D-75392 Deckenpfronn, Germany
Toll-Free: 0800 6397678 TEL: +49 (0) 7056 9398-0
FAX: +49 (0) 7056 9398-29 e-mail: [email protected]
United Kingdom: OMEGA Engineering Ltd.
ISO 9001 Certified One Omega Drive, River Bend Technology Centre, Northbank
Irlam, Manchester M44 5BD United Kingdom
Toll-Free: 0800-488-488 TEL: +44 (0) 161 777-6611
FAX: +44 (0) 161 777-6622 e-mail: [email protected]
OMEGAnet®Online Service Internet e-mail
omega.com [email protected]
It is the policy of OMEGA Engineering, Inc. to comply with all worldwide safety and EMC/EMI
regulations that apply. OMEGA is constantly pursuing certification of its products to the European New
Approach Directives. OMEGA will add the CE mark to every appropriate device upon certification.
The information contained in this document is believed to be correct, but OMEGA accepts no liability for any
errors it contains, and reserves the right to alter specifications without notice.
WARNING: These products are not designed for use in, and should not be used for, human applications.
Page 3
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 ..............................
Chapter 1
Introducing the OM-USB-Temp................................................................................................................. 6
Overview: OM-USB-TEMP features ....................................................................................................................... 6
OM-USB-TEMP block diagram............................................................................................................................... 7
Software features ....................................................................................................................................................... 7
Connecting a OM-USB-TEMP to your computer is easy........................................................................................ 8
Chapter 2
Installing the OM-USB-TEMP .................................................................................................................... 9
What comes with your OM-USB-TEMP shipment?................................................................................................ 9
Hardware.....................................................................................................................................................................................9
Additional documentation ..........................................................................................................................................................9
Unpacking the OM-USB-TEMP............................................................................................................................... 9
Installing the software ............................................................................................................................................. 10
Installing the OM-USB-TEMP ............................................................................................................................... 10
Configuring the OM-USB-TEMP........................................................................................................................... 10
Calibrating the OM-USB-TEMP ............................................................................................................................ 10
Chapter 3
Sensor Connections................................................................................................................................. 11
Screw terminal pin out ............................................................................................................................................ 11
Sensor input terminals (C0H/C0L to C7H/C7L).....................................................................................................................12
Current excitation output terminals (±I1 to ±I4) .....................................................................................................................12
Four-wire, two sensor common terminals (4W01 to 4W67) ..................................................................................................13
Two sensor common terminals (IC01 to IC67).......................................................................................................................13
Ground terminals (GND)..................................................................................................................................
Power terminals (+5V) .............................................................................................................................................................13
Digital terminals (DIO0 to DIO7)............................................................................................................................................13
CJC sensors.........................................................................
Thermocouple connections ..................................................................................................................................... 13
Wiring configuration ................................................................................................................................................................13
RTD and thermistor connections ............................................................................................................................ 14
Two-wire configuration............................................................................................................................................................14
Three-wire configuration..........................................................................................................................................................15
Four-wire configuration............................................................................................................................................................16
Semiconductor sensor measurements ..................................................................................................................... 17
Wiring configuration ................................................................................................................................................................17
Digital I/O connections ........................................................................................................................................... 17
Chapter 4
Functional Details ..................................................................................................................................... 19
Thermocouple measurements ................................................................................................................................. 19
Cold junction compensation (CJC)..........................................................................................................................................19
Data linearization......................................................................................................................................................................19
Open-thermocouple detection (OTD) ......................................................................................................................................19
RTD and thermistor measurements ........................................................................................................................ 20
................................................................................................. 5
........................13
......................................................................................................13
3
Page 4
OM-USB-TEMP User's Guide
Data linearization......................................................................................................................................................................20
USB connector......................................................................................................................................................... 20
LED.......................................................................................................................................................................... 20
Power ....................................................................................................................................................................... 20
Chapter 5
Specifications............................................................................................................................................ 21
Analog input ............................................................................................................................................................ 21
Channel configurations ........................................................................................................................................... 22
Compatible sensors......................................................................................
............................................................ 22
Accuracy .................................................................................................................................................................. 23
Thermocouple measurement accuracy.....................................................................................................................................23
Semiconductor sensor measurement accuracy ........................................................................................................................23
RTD measurement accuracy ....................................................................................................................................................24
Thermistor measurement accuracy ..........................................................................................................................................24
Throughput rate ....................................................................................................................................................... 25
Digital input/output ................................................................................................................................................. 25
Memory.................................................................................................................................................................... 25
Microcontroller........................................................................................................................................................ 26
USB +5V voltage .................................................................................................................................................... 26
Power ....................................................................................................................................................................... 26
USB specifications .................................................................................................................................................. 26
Current excitation outputs (Ix+).............................................................................................................................. 27
Environmental ............
............................................................................................................................................. 27
Mechanical............................................................................................................................................................... 27
Screw terminal connector type and pin out ................................................................................................
Screw terminal pin out..............................................................................................................................................................28
............ 28
4
Page 5
About this User’s Guide
What you will learn from this user’s guide
This user’s guide explains how to install, configure, and use the OM-USB-TEMP so that you get the most out of
its USB-based temperature measurement features.
This user’s guide also refers you to related documents available on our web site, and to technical support
resources.
Conventions in this user’s guide
For more information on …
Text presented in a box signifies additional information and helpful hints related to the subject matter you are
reading.
Caution! Shaded caution statements present information to help you avoid injuring yourself and others,
damaging your hardware, or losing your data.
<#:#> Angle brackets that enclose numbers separated by a colon signify a range of numbers, such as those assigned
to registers, bit settings, etc.
bold text Bold text is used for the names of objects on the screen, such as buttons, text boxes, and check boxes. For
example:
1. Insert the disk or CD and click the OK button.
Preface
italic text Italic text is used for the names of manuals and help topic titles, and to emphasize a word or phrase. For
example:
Never touch the exposed pins or circuit connections on the board.
Where to find more information
For additional information relevant to the operation of your hardware, refer to the Documents subdirectory
where you installed the software, or search for your device on our website at www.omega.com.
5
Page 6
Introducing the OM-USB-TEMP
Overview: OM-USB-TEMP features
Chapter 1
This user's guide contains all of the information you need to connect the OM-USB-TEMP
to the signals you want to measure.
The OM-USB-TEMP is a USB 2.0 full-speed, temperature measurement module that is supported under popular
Microsoft
2.0 ports.
The OM-USB-TEMP provides eight differential input channels that are software programmable for different
sensor categories including thermocouple, RTDs, thermistors and Semiconductor sensors. Eight independent,
TTL-compatible digital I/O channels are provided to monitor TTL-level inputs, communicate with external
devices, and to generate alarms. The digital I/O channels are software programmable for input or output.
With the OM-USB-TEMP, you can take measurements from four sensor categories:
Thermocouple – types J, K, R, S, T, N, E, and B
Resistance temperature detectors (RTDs) – 2, 3, or 4-wire measurements of 100 Ω platinum RTDs
Thermistors – 2, 3, or 4-wire measurements
Semiconductor temperature sensors – LM36 or equivalent
The OM-USB-TEMP provides a 24-bit analog-to-digital (A/D) converter for each pair of differential analog
input channels. Each pair of differential inputs constitutes a channel pair.
You can connect a different category of sensor to each channel pair, but you cannot mix categories among the
channels that constitute a channel pair (although it is permissible to mix thermocouple types).
The OM-USB-TEMP provides two integrated cold junction compensation (CJC) sensors for thermocouple
measurements, and built-in current excitation sources for resistive sensor measurements.
An open thermocouple detection feature lets you detect a broken thermocouple. An on-board microprocessor
automatically linearizes the measurement data according to the sensor category.
®
Windows® operating systems. The OM-USB-TEMP is fully compatible with both USB 1.1 and USB
to your computer and
The OM-USB-TEMP is a standalone plug-and-play module which draws power from the USB cable. No
external power supply is required. All configurable options are software programmable.
The OM-USB-TEMP is fully software calibrated.
6
Page 7
OM-USB-TEMP User's Guide Introducing the OM-USB-TEMP
OM-USB-TEMP block diagram
OM-USB-TEMP
functions are illustrated in the block diagram shown here.
Figure 1. OM-USB-TEMP functional block diagram
Software features
For information on the features of InstaCal and the other software included with your OM-USB-TEMP, refer to
the OMB-DAQ-2416 Series and OM-USB Series Software User’s Guide that shipped with your device.
7
Page 8
OM-USB-TEMP User's Guide Introducing the OM-USB-TEMP
Connecting a OM-USB-TEMP to your computer is easy
Installing a data acquisition device has never been easier.
The OM-USB-TEMP relies upon the Microsoft Human Interface Device (HID) class drivers. The HID class
drivers ship with every copy of Windows that is designed to work with USB ports. We use the Microsoft
HID because it is a standard, and its performance delivers full control and maximizes data transfer rates for
your OM-USB-TEMP. No third-party device driver is required.
The OM-USB-TEMP is plug-and-play. There are no jumpers to position, DIP switches to set, or interrupts
to configure.
You can connect the OM-USB-TEMP before or after you install the software, and without powering down
your computer first. When you connect an HID to your system, your computer automatically detects it and
configures the necessary software. You can connect and power multiple HID peripherals to your system
using a USB hub.
You can connect your system to various devices using a standard four-wire cable. The USB connector
replaces the serial and parallel port connectors with one standardized plug and port combination.
You do not need a separate power supply module. The USB automatically delivers the electrical power
required by each peripheral connected to your system.
Data can flow two ways between a computer and peripheral over USB connections.
8
Page 9
9
Installing the OM-USB-TEMP
What comes with your OM-USB-TEMP shipment?
The following items are shipped with the OM-USB-TEMP.
Hardware
OM-USB-TEMP
Chapter 2
USB cable (2 meter length)
Additional documentation
In addition to this hardware user's guide, you should also receive the OMB-DAQ-2416 Series and OM-USB
Series Software User’s Guide. This booklet supplies a brief description of the software you received with your
OM-USB-TEMP and information regarding installation of that software. Please read this booklet completely
before installing any software or hardware.
Unpacking the OM-USB-TEMP
As with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the OM-USB-TEMP 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, notify Omega Engineering immediately by phone, fax, or e-mail.
Page 10
OM-USB-TEMP User's Guide Installing the OM-USB-TEMP
Installing the software
Refer to the OMB-DAQ-2416 Series and OM-USB Series Software User’s Guide for instructions on installing
the software on the OMB-DAQ-2416 Series and OM-USB Series Data Acquisition Software CD. This booklet is
available in PDF at http://omega.com/manuals.
We recommend that you download the latest Windows Update onto your computer before installing and
operating the OM-USB-TEMP.
Installing the OM-USB-TEMP
To connect the OM-USB-TEMP 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
power and communication to the OM-USB-TEMP.
When you connect the OM-USB-TEMP for the first time, a
XP) or dialog (other Windows versions) opens as the OM-USB-TEMP is detected. When this balloon or dialog
closes, the installation is complete. The
communication is established between the OM-USB-TEMP and your computer.
Caution! Do not disconnect any device from the USB bus while the computer is communicating with the
OM-USB-TEMP, or you may lose data and/or your ability to communicate with the OM-USBTEMP.
If the LED turns off
If the LED is lit but then turns off, the computer has lost communication with the OM-USB-TEMP. To restore
communication, disconnect the USB cable from the computer, and then reconnect it. This should restore
communication, and the LED should turn back on.
USB LED should flash and then remain lit. This indicates that
Found New Hardware popup balloon (Windows
Configuring the OM-USB-TEMP
All hardware configuration options on the OM-USB-TEMP are programmable with software. Use InstaCal to set
the sensor type for each channel. The configurable options dynamically update according to the selected sensor
category. Configuration options are stored on the OM-USB-TEMP 's isolated microcontroller in EEPROM,
which is non-volatile memory on the OM-USB-TEMP module. Configuration options are loaded on power up.
Default configuration
The factory default configuration is Disabled. The Disabled mode disconnects the analog inputs from the
terminal blocks and internally grounds all of the A/D inputs. This mode also disables each of the current
excitation sources.
Warm up
Allow the OM-USB-TEMP to warm up for 30 minutes before taking measurements. This warm up time
minimizes thermal drift and achieves the specified rated accuracy of measurements.
For RTD or thermistor measurements, this warm-up time is also required to stabilize the internal current
reference.
Calibrating the OM-USB-TEMP
The OM-USB-TEMP is fully calibrated via software. InstaCal prompts you to run its calibration utility when
you change from one sensor category to another.
Allow the OM-USB-TEMP to operate for at least 30 minutes before calibrating. This warm up time minimizes
thermal drift and achieves the specified rated accuracy of measurements.
10
Page 11
Sensor Connections
The OM-USB-TEMP supports the following temperature sensor types:
Thermocouple – types J, K, R, S, T, N, E, and B
Resistance temperature detectors (RTDs) – 2, 3, or 4-wire measurement modes of 100 _ platinum RTDs.
Thermistors – 2, 3, or 4-wire measurement modes.
Semiconductor temperature sensors – LM36 or equivalent
Sensor selection
The type of sensor you select will depend on your application needs. Review the temperature ranges and
accuracies of each sensor type to determine which is best suited for your application.
Screw terminal pin out
The OM-USB-TEMP has four rows of screw terminals — two rows on the top edge of the housing, and two
rows on the bottom edge. Each row has 26 connections. Between each bank of screw terminals are two
integrated CJC sensors used for thermocouple measurements. Signals are identified in Figure 2.
Chapter 3
Figure 2. OM-USB-TEMP screw terminal pin numbers
11
Page 12
OM-USB-TEMP User's Guide Sensor Connections
OM-USB-TEMP screw terminal descriptions
Pin Signal
Name
1 I1+ CH0/CH1 current excitation source 27 I4- CH6/CH7 current excitation return
2 NC Not connected 28 GND Ground
3 C0H CH0 sensor input (+) 29 C7L CH7 sensor input (-)
4 C0L CH0 sensor input (-) 30 C7H CH7 sensor input (+)
5 4W01 CH0/CH1 4-wire, 2 sensor common 31 IC67 CH6/CH7 2 sensor common
6 IC01 CH0/CH1 2-sensor common 32 4W67 CH6/CH7 4-wire, 2 sensor common
7 C1H CH1 sensor input (+) 33 C6L CH6 sensor input (-)
8 C1L CH1 sensor input (-) 34 C6H CH6 sensor input (+)
9 GND Ground 35 NC Not connected
10 I1- CH0/CH1 current excitation return 36 I4+ CH6/CH7 current excitation source
CJC sensor CJC sensor
11 I2+ CH2/CH3 current excitation source 37 I3- CH4/CH5 current excitation return
12 NC Not connected 38 GND Ground
13 C2H CH2 sensor input (+) 39 C5L CH5 sensor input (-)
14 C2L CH2 sensor input (-) 40 C5H CH5 sensor input (+)
15 4W23 CH2/CH3 4-wire, 2 sensor common 41 IC45 CH4/CH5 2 sensor common
16 IC23 CH2/CH3 2 sensor common 42 4W45 CH4/CH5 4-wire, 2 sensor common
17 C3H CH3 sensor input (+) 43 C4L CH4 sensor input (-)
18 C3L CH3 sensor input (-) 44 C4H CH4 sensor input (+)
19 GND Ground 45 NC Not connected
20 I2- CH2/CH3 current excitation return 46 I3+ CH4/CH5 current excitation source
21 +5V +5V output 47 +5V +5V output
22 GND Ground 48 GND Ground
23 DIO0 Digital Input/Output 49 DIO7 Digital Input/Output
24 DIO1 Digital Input/Output 50 DIO6 Digital Input/Output
25 DIO2 Digital Input/Output 51 DIO5 Digital Input/Output
26 DIO3 Digital Input/Output 52 DIO4 Digital Input/Output
Pin Description Pin Signal
Name
Pin Description
Use 16 AWG to 30 AWG wire for your signal connections.
Tighten screw terminal connections
When making connections to the screw terminals, be sure to tighten the screw until tight. Simply touching the
top of the screw terminal is not sufficient to make a proper connection.
Sensor input terminals (C0H/C0L to C7H/C7L)
You can connect up to eight temperature sensors to the differential sensor inputs (C0H/C0L to C7H/C7L).
Supported sensor categories include thermocouples, RTDs, thermistors, or semiconductor sensors.
Do not mix sensor categories within channel pairs. You can mix thermocouple types (J, K, R, S, T, N, E, and B)
within channel pairs, however.
Do not connect two different sensor categories to the same channel pair
The OM-USB-TEMP provides a 24 bit A/D converter for each channel pair. Each channel pair can monitor one
sensor category. To monitor a sensor from a different category, connect the sensor to a different channel pair
(input terminals).
Current excitation output terminals (±I1 to ±I4)
The OM-USB-TEMP has four dedicated pairs of current excitation output terminals (±I1 to ±I4). These terminals
have a built-in precision current source to provide excitation for the resistive sensors used for RTD and
thermistor measurements.
Each current excitation terminal is dedicated to one pair of sensor input channels:
I1+ is the current excitation source for channel 0 and channel 1
I2+ is the current excitation source for channel 2 and channel 3
I3+ is the current excitation source for channel 4 and channel 5
I4+ is the current excitation source for channel 6 and channel 7
12
Page 13
OM-USB-TEMP User's Guide Sensor Connections
Four-wire, two sensor common terminals (4W01 to 4W67)
These terminals are used as the common connection for four-wire configurations with two RTD or thermistor
sensors.
Two sensor common terminals (IC01 to IC67)
These terminals are used as the common connection for two-wire configurations with two RTD or thermistor
sensors.
Ground terminals (GND)
The six ground terminals (GND) provide a common ground for the input channels and DIO bits and are isolated
(500 VDC) from the USB GND.
Power terminals (+5V)
The two +5V output terminals are isolated (500 VDC) from the USB +5V.
Digital terminals (DIO0 to DIO7)
You can connect up to eight digital I/O lines to the screw terminals labeled DIO0 to DIO7. Each terminal is
software configurable for input or output.
CJC sensors
The OM-USB-TEMP 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.
Thermocouple connections
A thermocouple consists of two dissimilar metals that are joined together at one end. When the junction of the
metals is heated or cooled, a voltage is produced that correlates to temperature.
The OM-USB-TEMP makes fully differential thermocouple measurements without the need of ground-
referencing resistors. A 32-bit floating point value in either a voltage or temperature format is returned by
software. An open thermocouple detection feature is available for each analog input which automatically detects
an open or broken thermocouple.
Use InstaCal to select the thermocouple type (J, K, R, S, T, N, E, and B) and one or more sensor input channels
to connect the thermocouple.
Wiring configuration
Connect the thermocouple to the OM-USB-TEMP using a differential configuration, as shown in Figure 3.
Figure 3. Typical thermocouple connection
The OM-USB-TEMP
referenced to earth ground is permissible as long as the isolation between the GND pins (9, 19, 28, 38) and earth
ground is maintained.
GND pins are isolated from earth ground, so connecting thermocouple sensors to voltages
13
Page 14
OM-USB-TEMP User's Guide Sensor Connections
When thermocouples are attached to conductive surfaces, the voltage differential between multiple
thermocouples must remain within ±1.4 V. For best results, we recommend the use of insulated or ungrounded
thermocouples when possible.
Maximum input voltage between analog input and ground
The absolute maximum input voltage between an analog input and the isolated GND pins is ±25 VDC when the
OM-USB-TEMP is powered on, and ±40 VDC when the OM-USB-TEMP is powered off.
If you need to increase the length of your thermocouple, use the same type of thermocouple wires to minimize
the error introduced by thermal EMFs.
RTD and thermistor connections
A resistance temperature detector (RTD) measures temperature by correlating the resistance of the RTD
element with temperature. A thermistor is a thermally-sensitive resistor that is similar to an RTD in that its
resistance changes with temperature — thermistors show a large change in resistance that is proportional to a
small change in temperature. The main difference between RTD and thermistor measurements is the method
used to linearize the sensor data.
RTDs and thermistors are resistive devices that require an excitation current to produce a voltage drop that can
be measured differentially across the sensor. The OM-USB-TEMP features four built-in current excitation
sources (±I1 to ±I4) for measuring resistive type sensors. Each current excitation terminal is dedicated to one
channel pair.
The OM-USB-TEMP makes two, three, and four-wire measurements of RTDs (100 Ω platinum type) and
thermistors.
Use InstaCal to select the sensor type and the wiring configuration. Once the resistance value is calculated, the
value is linearized in order to convert it to a temperature value. A 32-bit floating point value in either
temperature or resistance is returned by software.
RTD maximum resistance
Resistance values greater than 660 Ω cannot be measured by the OM-USB-TEMP in the RTD mode. The 660 Ω
resistance limit includes the total resistance across the current excitation (±Ix) pins, which is the sum of the
RTD resistance and the lead resistances.
Thermistor maximum resistance
Resistance values greater than 180k ohms cannot be measured by the OM-USB-TEMP in the thermistor mode.
The 180 k Ω resistance limit includes the total resistance across the current excitation (±Ix) pins, which is the
sum of the thermistor resistance and the lead resistance.
Two-wire configuration
The easiest way to connect an RTD sensor or thermistor to the OM-USB-TEMP is with a two-wire
configuration, since it requires the fewest connections to the sensor. With this method, the two wires that
provide the RTD sensor with its excitation current also measure the voltage across the sensor.
Since RTDs exhibit a low nominal resistance, measurement accuracy can be affected due to the lead wire
resistance. For example, connecting lead wires that have a resistance of 1 Ω (0.5 Ω each lead) to a 100 Ω platinum
RTD will result in a 1% measurement error.
With a two-wire configuration, you can connect either one sensor per channel pair, or two sensors per channel
pair.
Two-wire, single-sensor
A two-wire single-sensor measurement configuration is shown in Figure 4.
14
Page 15
OM-USB-TEMP User's Guide Sensor Connections
15
Figure 4. Two-wire, single RTD or thermistor sensor measurement configuration
When you select a two-wire single sensor configuration with InstaCal, connections to C#H and C#L are made
internally.
Two-wire, two sensor
A two-wire, two-sensor measurement configuration is shown in Figure 5.
Figure 5. Two-wire, two RTD or thermistor sensors measurement configuration
When you select a two-wire, two sensor configuration with InstaCal, connections to C#H (first sensor) and
C#H/C#L (second sensor) are made internally.
When configured for two-wire mode, both sensors must be connected to obtain proper measurements.
Three-wire configuration
A three-wire configuration compensates for lead-wire resistance by using a single voltage sense connection.
With a three-wire configuration, you can connect only one sensor per channel pair. A three-wire measurement
configuration is shown in Figure 6.
Figure 6. Three-wire RTD or thermistor sensor measurement configuration
When you select a three-wire sensor configuration with InstaCal, the OM-USB-TEMP measures the lead
resistance on the first channel (C#H/C#L) and measures the sensor itself using the second channel (C#H/C#L).
This configuration compensates for any lead-wire resistance and temperature change in lead-wire resistance.
Connections to C#H for the first channel and C#H/C#L of the second channel are made internally.
Three-wire compensation
For accurate three wire compensation, the individual lead resistances connected to the ±I# pins must be of equal
resistance value.
Page 16
OM-USB-TEMP User's Guide Sensor Connections
16
Four-wire configuration
With a four-wire configuration, connect two sets of sense/excitation wires at each end of the RTD or thermistor
sensor. This configuration completely compensates for any lead-wire resistance and temperature change in lead-
wire resistance.
Connect your sensor with a four-wire configuration when your application requires very high accuracy
measurements. Examples of a four-wire single-sensor measurement configuration are shown in Figure 7 and
Figure 8.
You can configure the OM-USB-TEMP with either a single sensor per channel or two sensors per channel pair.
Four-wire, single-sensor
A four-wire, single-sensor connected to the first channel of a channel pair is shown in Figure 7.
Figure 7. Four-wire, single RTD or thermistor sensor measurement configuration
A four-wire, single-sensor connected to the second channel of a channel pair is shown in Figure 8.
Figure 8. Four-wire, single RTD or thermistor sensor measurement configuration
A four-wire, two-sensor measurement configuration is shown in Figure 9.
Figure 9. Four-wire, two RTD or thermistor sensors measurement configuration
When configured for four-wire, two sensor mode, both sensors must be connected to obtain proper
measurements.
Page 17
OM-USB-TEMP User's Guide Sensor Connections
thermocouples and RTDs. However, semiconductor sensors can be accurate, inexpensive and easy to interface
with other electronics for display and control.
The OM-USB-TEMP makes high-resolution measurements of semiconductor sensors, such as the LM36 or
equivalent, and returns a 32-bit floating point value in either a voltage or temperature format.
Use InstaCal to select the sensor type (TMP36 or equivalent) and the sensor input channel to connect the
sensor.
Wiring configuration
You can connect a TMP36 (or equivalent) semiconductor sensor to the OM-USB-TEMP using a single-ended
configuration, as shown in Figure 10. The OM-USB-TEMP also provides
sensor.
+5V and GND pins for powering the
Figure 10. Semiconductor sensor measurement configuration
The software outputs the measurement data as a 32-bit floating point value in either voltage or temperature.
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 kΩ 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 OM-USB-TEMP digital I/O terminals to detect the
state of any TTL-level input. Refer to the schematic shown in Figure 11. If you set the switch to the +5V input,
DIO0 reads TRUE (1). If you move the switch to GND, DIO0 reads FALSE (0).
Figure 11. Schematic showing switch detection by digital channel DIO0
Caution! All ground pins on the OM-USB-TEMP (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 http://www.omega.com/manuals/manualpdf/M4830.pdf).
17
Page 18
Functional Details
Thermocouple measurements
A thermocouple consists of two dissimilar metals that are joined together at one end. When the junction of the
metals is heated or cooled, a voltage is produced that correlates to temperature.
The OM-USB-TEMP 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 OM-USB-TEMP 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 OM-
USB-TEMP 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 OM-USB-TEMP subtracts the cold junction voltage
from the thermocouple voltage.
The OM-USB-TEMP has two high-resolution temperature sensors that are integrated into the design of the OM-
USB-TEMP. 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 by subtracting the calculated cold junction voltage from the analog input's thermocouple voltage
measurement.
Chapter 4
Increasing the thermocouple length
If you need to increase the length of your thermocouple, use the same type of thermocouple wires to minimize
the error introduced by thermal EMFs.
Data linearization
After the CJC correction is performed on the measurement data, an on-board microcontroller automatically
linearizes 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 or
temperature).
Open-thermocouple detection (OTD)
The OM-USB-TEMP is equipped with an open-thermocouple detection for each analog input channel. With
OTD, any open-circuit or short-circuit condition at the thermocouple sensor is detected by the software. An
open channel is detected by driving the input voltage to a negative value outside the range of any thermocouple
output. The software recognizes this as an invalid reading and flags the appropriate channel. The software
continues to sample all channels when OTD is detected.
Input leakage current
With open-thermocouple detection enabled, 105 nA (max.) of input leakage current is injected into the
thermocouple. 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
18
Page 19
OM-USB-TEMP 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 wire
by using a wire with a larger diameter. With open-thermocouple detection disabled, 30 nA (max) of input
leakage current is injected into the thermocouple.
RTD and thermistor measurements
RTDs and thermistors are resistive devices that require an excitation current to produce a voltage drop that can
be measured differentially across the sensor. The OM-USB-TEMP measures the sensor resistance by forcing a
known excitation current through the sensor and then measuring (differentially) the voltage across the sensor to
determine its resistance.
After the voltage measurement is made, the resistance of the RTD is calculated using Ohms law – the sensor
resistance is calculated by dividing the measured voltage by the current excitation level (±
of the ±
Once the resistance value is calculated, the value is linearized in order to convert it to a temperature value. The
measurement is returned by software as a 32-bit floating point value in a voltage, resistance or temperature
format.
Ix source is stored in local memory.
Data linearization
An on-board microcontroller automatically performs linearization on RTD and thermistor measurements.
RTD measurements are linearized using a Callendar-Van Dusen coefficients algorithm (you select DIN,
SAMA, or ITS-90).
Thermistor measurements are linearized using a Steinhart-Hart linearization algorithm (you supply the
coefficients from the sensor manufacturer's data sheet).
Ix) source. The value
USB connector
The USB connector provides +5V power and communication. No external power supply is required.
LED
The LED indicates the communication status of the OM-USB-TEMP. It uses up to 5 mA of current. The table
below defines the function of the OM-USB-TEMP LED.
LED Illumination
LED
Illumination
Steady green The OM-USB-TEMP is connected to a computer or external USB hub.
Pulsing green Data is being transferred.
Indication
Upon connection, the LED should flash three times and then remain lit (indicates a successful
installation).
Power
The two +5V terminals are isolated (500 VDC) from the USB +5V.
Caution! Each +5V terminal is an output. Do not connect to an external power supply or you may damage
the OM-USB-TEMP and possibly the computer.
19
Page 20
Chapter 5
Specifications
All specifications are subject to change without notice.
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Analog input
Table 1. Generic analog input specifications
Parameter
Conditions
Specification
A/D converters
Four dual 24-bit, Sigma-Delta type
Number of channels
8 differential
Input isolation
500 VDC minimum between field wiring and
USB interface
Channel configuration
Software programmable to match sensor type
Thermocouple
±0.080 V
RTD
0 to 0.5 V
Thermistor
0 to 2 V
Differential input voltage range
for the various sensor categories
Semiconductor sensor
0 to 2.5 V
Absolute maximum input voltage
±C0x through ±C7x relative to
GND (pins 9, 19, 28, 38)
±25 V power on, ±40 V power off.
Input impedance
5 Gigohm, min.
Open thermocouple detect
disabled
30 nA max.
Input leakage current
Open thermocouple detect
enabled
105 nA max.
Normal mode rejection ratio
fIN = 60 Hz
90 dB min.
Common mode rejection ratio
fIN = 50 Hz/60 Hz
100 dB min.
Resolution
24 bits
No missing codes
24 bits
Input coupling
DC
Warm-up time
30 minutes min.
Open thermocouple detect
Automatically enabled when the channel pair is
configured for thermocouple sensor.
The maximum open detection time is 3!seconds.
15 °C to 35 °C
±0.25 °C typ.,±0.5 °C max.
CJC sensor accuracy
0 °C to 70 °C
–1.0 to +0.5 °C max
20
Page 21
OM-USB-TEMP User's Guide Specifications
Channel configurations
Table 2. Channel configuration specifications
Sensor Category Conditions Max number of
sensors (all channels
configured alike)
Disabled
Thermocouple 8 differential channels
Semiconductor sensor 8 differential channels
RTD and thermistor
Note 1: Internally, the OM-USB-TEMP has four, dual-channel, fully differential A/Ds providing a total of
eight differential channels. The analog input channels are therefore configured in four channel
pairs with CH0/CH1 sensor inputs, CH2/CH3 sensor inputs, CH4/CH5 sensor inputs, and
CH6/CH7 sensor inputs paired together. This "channel-pairing" requires the analog input channel
pairs be configured to monitor the same category of temperature sensor. Mixing different sensor
types of the same category (such as a type J thermocouple on channel 0 and a type T
thermocouple on channel 1) is valid.
Note 2: Channel configuration information is stored in the EEPROM of the isolated microcontroller by
the firmware whenever any item is modified. Modification is performed by commands issued
over USB from an external application, and the configuration is made non-volatile through the
use of the EEPROM.
Note 3: The factory default configuration is Disabled. The Disabled mode will disconnect the analog
inputs from the terminal blocks and internally ground all of the A/D inputs. This mode also
disables each of the current excitation sources.
2-wire input configuration with a single sensor per channel pair 4 differential channels
2-wire input configuration with two sensors per channel pair 8 differential channels
3-wire configuration with a single sensor per channel pair 4 differential channels
4-wire input configuration with a single sensor per channel pair 4 differential channels
4-wire input configuration with two sensors per channel pair 8 differential channels
Compatible sensors
Table 3. Compatible sensor type specifications
Parameter Conditions
Thermocouple
RTD
Thermistor Standard 2,252 ohm through 30,000 ohm
Semiconductor / IC TMP36 or equivalent
J: -210 °C to 1200 °C
K: -270 °C to 1372 °C
R: -50 °C to 1768 °C
S: -50 °C to 1768 °C
T: -270 °C to 400 °C
N: -270 °C to 1300 °C
E: -270 °C to 1000 °C
B: 0 °C to 1820 °C
100 ohm PT (DIN 43760: 0.00385 ohms/ohm/°C)
100 ohm PT (SAMA: 0.003911 ohms/ohm/°C)
100 ohm PT (ITS-90/IEC751:0.0038505 ohms/ohm/°C)
21
Page 22
OM-USB-TEMP User's Guide Specifications
Accuracy
Thermocouple measurement accuracy
Table 4. Thermocouple accuracy specifications, including CJC measurement error
Sensor Type Maximum error Typical error Temperature range
±1.499 °C ±0.507 °C -210 to 0 °CJ
±0.643 °C ±0.312 °C 0 to 1200 °C
±1.761 °C ±0.538 °C -210 to 0 °CK
±0.691 °C ±0.345 °C 0 to 1372 °C
±2.491°C ±0.648 °C -50 to 250 °CS
±1.841 °C ±0.399 °C 250 to 1768.1 °C
±2.653 °C ±0.650 °C -50 to 250 °CR
±1.070 °C ±0.358 °C 250 to 1768.1 °C
±1.779 °C ±0.581 °C 250 to 700 °CB
±0.912 °C ±0.369 °C 700 to 1820 °C
±1.471 °C ±0.462 °C -200 to 0 °CE
±0.639 °C ±0.245 °C 0 to 1000 °C
±1.717 °C ±0.514 °C -200 to 0 °CT
±0.713 °C ±0.256 °C 0 to 600 °C
±1.969 °C ±0.502 °C -200 to 0 °CN
±0.769 °C ±0.272 °C 0 to 1300 °C
Note 4: Thermocouple measurement accuracy 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 the OM-USB-TEMP 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 not include inherent thermocouple
error. Please contact your thermocouple supplier for details on the actual thermocouple error.
Note 5: Thermocouples must be connected to the OM-USB-TEMP such that they are floating with respect
to GND (pins 9, 19, 28, 38). The OM-USB-TEMP 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 6: When thermocouples are attached to conductive surfaces, the voltage differential between
multiple thermocouples must remain within ±1.4 V. For best results we recommend the use of
insulated or ungrounded thermocouples when possible.
Semiconductor sensor measurement accuracy
Table 5. Semiconductor sensor accuracy specifications
Sensor Type Temperature Range (°C) Maximum Accuracy Error
TMP36 or equivalent -40 to 150 °C ±0.50 °C
Note 7: Error shown does not include errors of the sensor itself. These specs are for one year while
operation of the OM-USB-TEMP
supplier for details on the actual sensor error limitations.
unit is between 15 °C and 35 °C. Please contact your sensor
22
Page 23
OM-USB-TEMP User's Guide Specifications
RTD measurement accuracy
Table 6. RTD measurement accuracy specifications
RTD Sensor
Temperature
PT100, DIN, US or
ITS-90
Note 8: Error shown does not include errors of the sensor itself. The sensor linearization is performed
-200°C to -150°C ±2.85 ±2.59
-150°C to -100°C ±1.24 ±0.97
-100°C to 0°C ±0.58 ±0.31
0°C to 100°C ±0.38 ±0.11
100°C to 300°C ±0.39 ±0.12
300°C to 600°C ±0.40 ±0.12
Maximum Accuracy Error (°C)
Ix+ = 210 µA
Typical Accuracy Error (°C)
Ix+ = 210 µA
using a Callendar-Van Dusen linearization algorithm. These specs are for one year while
operation of the OM-USB-TEMP unit is between 15 °C and 35 °C. The specification does not
include lead resistance errors for 2-wire RTD connections. Please contact your sensor supplier for
details on the actual sensor error limitations.
Note 9: Resistance values greater than 660 ohms cannot be measured by the OM-USB-TEMP in the RTD
mode. The 660 ohm resistance limit includes the total resistance across the current excitation
(±Ix) pins, which is the sum of the RTD resistance and the lead resistances.
Note 10: For accurate three wire compensation, the individual lead resistances connected to the ±Ix pins
must be of equal value.
Thermistor measurement accuracy
Table 7. Thermistor measurement accuracy specifications
Thermistor
2252 _ -40 to120 °C ±0.05
3000 _ -40 to120 °C ±0.05
5000 _ -35 to120 °C ±0.05
10000 _ -25 to120 °C ±0.05
30000 _ -10 to120 °C ±0.05
Note 11: Error shown does not include errors of the sensor itself. The sensor linearization is performed
Temperature Range Maximum Accuracy Error (°C)
Ix+ = 10 µA
using a Steinhart-Hart linearization algorithm. These specs are for one year while operation of the
OM-USB-TEMP unit is between 15 °C and 35 °C. The specification does not include lead
resistance errors for 2-wire thermistor connections. Please contact your sensor supplier for details
on the actual sensor error limitations. Total thermistor resistance on any given channel pair must
not exceed 180 k ohms. Typical resistance values at various temperatures for supported
thermistors are shown in Table 8.
Table 8. Typical thermistor resistance specifications
Temp 2252 Ω
thermistor
-40 °C 76 kΩ 101 kΩ 168 kΩ 240 kΩ (Note 12) 885 kΩ (Note 12)
-35 °C 55 kΩ 73 kΩ 121 kΩ 179 kΩ 649 kΩ (Note 12)
-30 °C 40 kΩ 53 kΩ 88 kΩ 135 kΩ 481 kΩ (Note 12)
-25 °C 29 kΩ 39 kΩ 65 kΩ 103 kΩ 360 kΩ (Note 12)
-20 °C 22 kΩ 29 kΩ 49 kΩ 79 kΩ 271 kΩ (Note 12)
-15 °C 16 kΩ 22 kΩ 36 kΩ 61 kΩ 206 kΩ (Note 12)
-10 °C 12 kΩ 17 kΩ 28 kΩ 48 kΩ 158 kΩ
-5 °C 9.5 kΩ 13 kΩ 21 kΩ 37 kΩ 122 kΩ
0 °C 7.4 kΩ 9.8 kΩ 16 kΩ 29 kΩ 95 kΩ
3000 Ω
thermistor
5 kΩ
thermistor
10 kΩ thermistor 30 kΩ thermistor
23
Page 24
OM-USB-TEMP User's Guide Specifications
Note 12: Resistance values greater than 180 k ohms cannot be measured by the OM-USB-TEMP in the
thermistor mode. The 180 k ohm resistance limit includes the total resistance across the current
excitation (±Ix) pins, which is the sum of the thermistor resistance and the lead resistances.
Note 13: For accurate three wire compensation, the individual lead resistances connected to the ±Ix pins
must be of equal value.
Throughput rate
Table 9. Throughput rate specifications
Number of Input Channels Maximum Throughput
1 2 Samples/second
2 2 S/s on each channel, 4 S/s total
3 2 S/s on each channel, 6 S/s total
4 2 S/s on each channel, 8 S/s total
5 2 S/s on each channel, 10 S/s total
6 2 S/s on each channel, 12 S/s total
7 2 S/s on each channel, 14 S/s total
8 2 S/s on each channel, 16 S/s total
Note 14: The analog inputs are configured to run continuously. Each channel is sampled twice per second.
The maximum latency between when a sample is acquired and the temperature data is provided
by the USB unit is approximately 0.5 seconds.
Digital input/output
Table 10. Digital input/output specifications
Digital type CMOS
Number of I/O 8 (DIO0 through DIO7)
Configuration Independently configured for input or output.
Power on reset is input mode.
Pull-up/pull-down configuration All pins pulled up to +5 V via 47 K resistors (default). Pull-down to ground
(GND) also available.
Digital I/O transfer rate (software paced)
Input high voltage 2.0 V min., 5.5 V absolute max.
Input low voltage 0.8 V max., –0.5 V absolute min.
Output low voltage (IOL = 2.5 mA) 0.7 V max.
Output high voltage (IOH = –2.5 mA) 3.8 V min.
Note 15: All ground pins on the OM-USB-TEMP (pins 9, 19, 28, 38) are common and are isolated from
Digital input – 50 port reads or single bit reads per second typ.
Digital output – 100 port writes or single bit writes per second typ.
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.
Memory
Table 11. Memory specifications
EEPROM 1,024 bytes isolated micro reserved for sensor configuration
256 bytes USB micro for external application use
Microcontroller
Table 12. Microcontroller specifications
Type Two high-performance 8-bit RISC microcontrollers
24
Page 25
OM-USB-TEMP User's Guide Specifications
Microcontroller
Table 12. Microcontroller specifications
Type Two high-performance 8-bit RISC microcontrollers
USB +5V voltage
Table 13. USB +5V voltage specifications
Parameter Conditions Specification
USB +5V (VBUS) input voltage
range
4.75 V min. to 5.25 V max.
Power
Table 14. Power specifications
Parameter Conditions Specification
Supply current USB enumeration <100 mA
Supply current
(Note 16)
User +5V output voltage range
(terminal block pin 21 and pin 47)
User +5V output current
(terminal block pin 21 and pin 47)
Isolation Measurement system to PC 500 VDC min.
Note 16: This is the total current requirement for the OM-USB-TEMP which includes up to 10 mA for the
status LED.
Note 17: Self-Powered Hub refers to a USB hub with an external power supply. Self-powered hubs allow
a connected USB device to draw up to 500 mA.
Continuous mode 140 mA typ.
Connected to self-powered hub. (Note 17) 4.75 V min. to
5.25 V max.
Bus-powered and connected to a self-powered
hub. (Note 17)
10 mA max.
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 15. USB specifications
USB device type USB 2.0 (full-speed)
Device compatibility USB 1.1, USB 2.0
Self-powered, 100 mA consumption max
USB cable type A-B cable, UL type AWM 2527 or equivalent. (min 24 AWG VBUS/GND,
min 28 AWG D+/D–)
USB cable length 3 meters max.
25
Page 26
OM-USB-TEMP User's Guide Specifications
Current excitation outputs (Ix+)
Table 16. Current excitation output specifications
Parameter Conditions Specification
Configuration 4 dedicated pairs:
±I1 - CH0/CH1
±I2 - CH2/CH3
±I3 - CH4/CH5
±I4 - CH6/CH7
Thermistor 10 µA typ.Current excitation output ranges
RTD 210 µA typ.
Tolerance ±5% typ.
Drift 200 ppm/°C
Line regulation 2.1 ppm/V max.
Load regulation 0.3 ppm/V typ.
Output compliance voltage
(relative to GND pins 9, 19, 28, 38)
Note 18: The OM-USB-TEMP has four current excitation outputs, with ±I1 dedicated to the CH0/CH1
analog inputs, ±I2 dedicated to CH2/CH3, ±I3 dedicated to CH4/CH5, and ±I4 dedicated to
CH6/CH7. The excitation output currents should always be used in this dedicated configuration.
Note 19: The current excitation outputs are automatically configured based on the sensor (thermistor or
RTD) selected.
3.90 V max.
-0.03 V min.
Environmental
Table 17. Environmental specifications
Operating temperature range 0 to 70 ° C
Storage temperature range -40 to 85 ° C
Humidity 0 to 90% non-condensing
Mechanical
Table 18. Mechanical specifications
Dimensions 127 mm (L) x 88.9 mm (W) x 35.56 (H)
User connection length 3 meters max.
26
Page 27
OM-USB-TEMP User's Guide Specifications
Screw terminal connector type and pin out
Table 19. Screw terminal connector specifications
Connector type Screw terminal
Wire gauge range 16 AWG to 30 AWG
Screw terminal pin out
Table 20. Screw terminal pin out
Pin Signal Name Pin Description Pin Signal Name Pin Description
1 I1+ CH0/CH1 current excitation source 27 I4- CH6/CH7 current excitation return
2 NC 28 GND
3 C0H CH0 sensor input (+) 29 C7L
4 C0L
5 4W01 CH0/CH1 4-wire, 2 sensor common 31 IC67 CH6/CH7 2 sensor common
6 IC01 CH0/CH1 2-sensor common 32 4W67 CH6/CH7 4-wire, 2 sensor common
7 C1H CH1 sensor input (+) 33 C6L
8 C1L
9 GND 35 NC
10 I1- CH0/CH1 current excitation return 36 I4+ CH6/CH7 current excitation source
CJC sensor CJC sensor
11 I2+ CH2/CH3 current excitation source 37 I3- CH4/CH5 current excitation return
12 NC 38 GND
13 C2H CH2 sensor input (+) 39 C5L
14 C2L
15 4W23 CH2/CH3 4-wire, 2 sensor common 41 IC45 CH4/CH5 2 sensor common
16 IC23 CH2/CH3 2 sensor common 42 4W45 CH4/CH5 4-wire, 2 sensor common
17 C3H CH3 sensor input (+) 43 C4L
18 C3L
19 GND 45 NC
20 I2- CH2/CH3 current excitation return 46 I3+ CH4/CH5 current excitation source
21 +5V +5V output 47 +5V +5V output
22 GND 48 GND
23 DIO0 Digital Input/Output 49 DIO7 Digital Input/Output
24 DIO1 Digital Input/Output 50 DIO6 Digital Input/Output
25 DIO2 Digital Input/Output 51 DIO5 Digital Input/Output
26 DIO3 Digital Input/Output 52 DIO4 Digital Input/Output
CH0 sensor input (
CH1 sensor input (
CH2 sensor input (
CH3 sensor input (
-)
-)
-)
-)
30 C7H CH7 sensor input (+)
34 C6H CH6 sensor input (+)
40 C5H CH5 sensor input (+)
44 C4H CH4 sensor input (+)
CH7 sensor input (
CH6 sensor input (
CH5 sensor input (
CH4 sensor input (
-)
-)
-)
-)
27
Page 28
WARRANTY/DISCLAIMER
OMEGA ENGINEERING, INC. warrants this unit to be free of defects in materials and workmanship for a
period of 13 months from date of purchase. OMEGA’s WARRANTY adds an additional one (1) month
grace period to the normal one (1) year product warranty to cover handling and shipping time. This
ensures that OMEGA’s customers receive maximum coverage on each product.
If the unit malfunctions, it must be returned to the factory for evaluation. OMEGA’s Customer Service
Department will issue an Authorized Return (AR) number immediately upon phone or written request.
Upon examination by OMEGA, if the unit is found to be defective, it will be repaired or replaced at no
charge. OMEGA’s WARRANTY does not apply to defects resulting from any action of the purchaser,
including but not limited to mishandling, improper interfacing, operation outside of design limits,
improper repair, or unauthorized modification. This WARRANTY is VOID if the unit shows evidence of
having been tampered with or shows evidence of having been damaged as a result of excessive corrosion;
or current, heat, moisture or vibration; improper specification; misapplication; misuse or other operating
conditions outside of OMEGA’s control. Components in which wear is not warranted, include but are not
limited to contact points, fuses, and triacs.
OMEGA is pleased to offer suggestions on the use of its various products. However,
OMEGA neither assumes responsibility for any omissions or errors nor assumes liability for any
damages that result from the use of its products in accordance with information provided by
OMEGA, either verbal or written. OMEGA warrants only that the parts manufactured by the
company will be as specified and free of defects. OMEGA MAKES NO OTHER WARRANTIES OR
REPRESENTATIONS OF ANY KIND WHATSOEVER, EXPRESSED OR IMPLIED, EXCEPT THAT OF
TITLE, AND ALL IMPLIED WARRANTIES INCLUDING ANY WARRANTY OF MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. LIMITATION OF
LIABILITY: The remedies of purchaser set forth herein are exclusive, and the total liability of
OMEGA with respect to this order, whether based on contract, warranty, negligence,
indemnification, strict liability or otherwise, shall not exceed the purchase price of the
component upon which liability is based. In no event shall OMEGA be liable for
consequential, incidental or special damages.
CONDITIONS: Equipment sold by OMEGA is not intended to be used, nor shall it be used: (1) as a “Basic
Component” under 10 CFR 21 (NRC), used in or with any nuclear installation or activity; or (2) in medical
applications or used on humans. Should any Product(s) be used in or with any nuclear installation or
activity, medical application, used on humans, or misused in any way, OMEGA assumes no responsibility
as set forth in our basic WARRANTY/DISCLAIMER language, and, additionally, purchaser will indemnify
OMEGA and hold OMEGA harmless from any liability or damage whatsoever arising out of the use of the
Product(s) in such a manner.
RETURN REQUESTS/INQUIRIES
Direct all warranty and repair requests/inquiries to the OMEGA Customer Service Department. BEFORE
RETURNING ANY PRODUCT(S) TO OMEGA, PURCHASER MUST OBTAIN AN AUTHORIZED RETURN
(AR) NUMBER FROM OMEGA’S CUSTOMER SERVICE DEPARTMENT (IN ORDER TO AVOID
PROCESSING DELAYS). The assigned AR number should then be marked on the outside of the return
package and on any correspondence.
The purchaser is responsible for shipping charges, freight, insurance and proper packaging to prevent
breakage in transit.
FOR WARRANTY
RETURNS, please have the
following information available BEFORE
contacting OMEGA:
1. Purchase Order number under which the product
was PURCHASED,
2. Model and serial number of the product under
warranty, and
3. Repair instructions and/or specific problems
relative to the product.
FOR NON-WARRANTY REPAIRS,
consult OMEGA
for current repair charges. Have the following
information available BEFORE contacting OMEGA:
1. Purchase Order number to cover the COST
of the repair,
2. Model and serial number of the product, and
3. Repair instructions and/or specific problems
relative to the product.
OMEGA’s policy is to make running changes, not model changes, whenever an improvement is possible. This affords
our customers the latest in technology and engineering.
OMEGA is a registered trademark of OMEGA ENGINEERING, INC.
© Copyright 2010 OMEGA ENGINEERING, INC. All rights reserved. This document may not be copied, photocopied,
reproduced, translated, or reduced to any electronic medium or machine-readable form, in whole or in part, without the
prior written consent of OMEGA ENGINEERING, INC.
Page 29
M4893/0410
Where Do I Find Everything I Need for
Process Measurement and Control?
OMEGA…Of Course!
Shop online at omega.com
SM
TEMPERATURE
䡺⻬
Thermocouple, RTD & Thermistor Probes, Connectors, Panels & Assemblies
䡺⻬
Wire: Thermocouple, RTD & Thermistor
䡺⻬
Calibrators & Ice Point References
䡺⻬
Recorders, Controllers & Process Monitors
䡺⻬
Infrared Pyrometers
PRESSURE, STRAIN AND FORCE
䡺⻬
Transducers & Strain Gages
䡺⻬
Load Cells & Pressure Gages
䡺⻬
Displacement Transducers
䡺⻬
Instrumentation & Accessories
FLOW/LEVEL
䡺⻬
Rotameters, Gas Mass Flowmeters & Flow Computers
䡺⻬
Air Velocity Indicators
䡺⻬
Turbine/Paddlewheel Systems
䡺⻬
Totalizers & Batch Controllers
pH/CONDUCTIVITY
䡺⻬
pH Electrodes, Testers & Accessories
䡺⻬
Benchtop/Laboratory Meters
䡺⻬
Controllers, Calibrators, Simulators & Pumps
䡺⻬
Industrial pH & Conductivity Equipment
DATA ACQUISITION
䡺⻬
Data Acquisition & Engineering Software
䡺⻬
Communications-Based Acquisition Systems
䡺⻬
Plug-in Cards for Apple, IBM & Compatibles
䡺⻬
Data Logging Systems
䡺⻬
Recorders, Printers & Plotters
HEATERS
䡺⻬
Heating Cable
䡺⻬
Cartridge & Strip Heaters
䡺⻬
Immersion & Band Heaters
䡺⻬
Flexible Heaters
䡺⻬
Laboratory Heaters
ENVIRONMENTAL
MONITORING AND CONTROL
䡺⻬
Metering & Control Instrumentation
䡺⻬
Refractometers
䡺⻬
Pumps & Tubing
䡺⻬
Air, Soil & Water Monitors
䡺⻬
Industrial Water & Wastewater Treatment
䡺⻬
pH, Conductivity & Dissolved Oxygen Instruments
Loading...