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USB-TEMP-AI User`s Guide

1. Sensor Sensor temperature Accuracy error Accuracy error Tempco Type range C maximum C Typical C C C J 210 2 028 0 707 0 031 0 0 835 0 278 1200 0 783 0 288 K 210 2 137 0 762 0 035 0 0 842 0 280 1372 0 931 0 389 S 50 1 225 0 435 0 021 250 0 554 0 195 1768 0 480 0 157 R 50 1 301 0 458 0 019 250 0 549 0 190 1768 0 400 0 134 B 250 2 193 2 185 0 001 700 0 822 0 819 1820 0 469 0 468 E 200 1 976 0 684 0 030 0 0 954 0 321 1000 0 653 0 240 T 200 2 082 0 744 0 035 21 USB TEMP AI User s Guide Specifications Sensor Sensor temperature Accuracy error Accuracy error Tempco Type range C maximum C Typical C C C 0 0 870 0 290 400 0 568 0 208 N 200 2 197 0 760 0 028 0 0 848 0 283 1300 0 653 0 245 Note 5 Thermocouple measurement accuracy specifications include polynomial 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 device between 15 C and 35 C There is a CJC sensor on each temperature sensor input 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 Contact your thermocouple supplier for details on the actual thermocouple accuracy error Note 6 Thermocouples must be connected to the d
2. 10 USB TEMP AI User s Guide Signal I O Connections Sensor input terminals TOH TOL to T3H T3L The USB TEMP AI 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 Q platinum RTDs Thermistors 2 3 or 4 wire measurement modes Semiconductor temperature sensors LM35 TMP35 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 You can connect up to four temperature sensors to the differential sensor inputs TOH TOL to T3H T3L 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 USB TEMP AI 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 pair of sensor input terminals Current excitation output terminals 11 and 12 The USB TEMP AI has two dedicated pairs of current excitation output terminals 11 and 12 These
3. 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 J1 is the current excitation source and I1 is the current excitation return for channel 0 and channel 1 12 is the current excitation source and I2 is the current excitation return for channel 2 and channel 3 Four wire two sensor common terminals 4W01 and 4W23 The 4W01 and 4W23 terminals are used as the common connection for four wire configurations with two RTD or thermistor sensors Sensor common terminals IT01 and IT23 The ITO1 and IT23 terminals are used as the common connection for two wire configurations with two RTD or thermistor sensors Digital terminals DIOO to DIO7 You can connect up to eight digital I O lines to the screw terminals labeled DIOO to DIO7 Each terminal is software configurable for input or output Counter terminal CTR The CTR terminal pin 40 is the input to the 32 bit event counter The internal counter increments when the TTL level transitions from low to high The counter can count events at frequencies of up to 1 MHz Caution All ground pins are common and 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
4. 23 dB TOx to T3x 50 Hz VOx to V3x 3 kHz 19 USB TEMP AI User s Guide Specifications Parameter Conditions Specification Maximum working VOx to V3x 10 25 V max voltage signal common mode Common mode rejection TOx to T3x fin 60 Hz 100 dB ratio VOx to V3x fin 60 Hz all input 83 dB ranges ADC resolution 24 bits ADC No missing codes 24 bits Input coupling DC Warm up time 30 minutes min Open thermocouple TOx to T3x detect Automatically enabled when the channel pair is configured for thermocouple sensor The maximum open detection time is 3 seconds CJC sensor accuracy TOx to T3x 15 C to 35 C 40 25 C typ 40 5 C max TOx to T3x 0 C to 70 C 1 0 to 0 75 C max Channel configurations Table 2 Channel configuration specifications Channel Category Conditions Max number of sensors all channels configured alike TOx T3x Disabled All temperature input channels are disconnected from screw See Note 4 terminals and internally connected to GND TOx T3x Thermocouple 4 differential channels Note 1 TOx T3x Semiconductor 4 differential channels sensor Note 1 TOx T3x RTD and 2 wire input configuration with a single sensor per channel 2 differential channels Thermistor pair Note 1 2 wire input configuration with two sensors per channel pair 4 differential channels 3 wire configuration wit
5. 360 KQ Note 13 20 22 kQ 29 kQ 49 KQ 79 kQ 271 kQ Note 13 15 16 kQ 22 kQ 36 KQ 61 kQ 206 kQ Note 13 10 12 kQ 17kQ 28 kQ 48 kQ 158kQ 5 9 5 KQ 13 kQ 21 kQ 37 kQ 122 kQ 0 7 4 KQ 9 8 KQ 16 kQ 29 kQ 95 kQ Note 13 Resistance values greater than 180 KQ cannot be measured by the device in the thermistor mode The 180 k Q 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 14 For accurate three wire compensation the individual lead resistances connected to the Ix pins must be of equal ohmic value To ensure this use connection leads of equal lengths 23 USB TEMP AI User s Guide Specifications Absolute Accuracy VOx V3x Table 9 Calibrated absolute accuracy specifications Range Absolute Accuracy mV 10 V 2 779 5 V 1 398 2 5 V 0 707 1 25 V 0 362 Note 15 When connecting differential inputs to floating input sources the user must provide a ground return path from each differential input to ground To do this simply connect a resistor from each of the differential inputs to GND A value of approximately 1 M Q can be used for most applications Note 16 All ground pins are common and are isolated from earth ground If a connection is made to earth ground when using both voltage inputs and conductive thermocouples the thermocouples are no longer isolated In this cas
6. 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 USB 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 Chapter 2 Installing the USB TEMP Al What comes with your shipment The following items are shipped with the USB TEMP AL Hardware USB TEMP AI USB cable Documentation In addition to this hardware user s guide you should also receive the 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 software or hardware Unpacking As with any electronic device you should take care while handling to avoid damage from static electricity Before removing the USB TEMP AI 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 mccdag com
7. 0 318 0 150 0 001 Note 9 The error shown does not include errors of the sensor itself The sensor linearization is performed using a Callendar Van Dusen linearization algorithm The accuracy and tempco specifications include the accuracy of the Callendar Van Dusen linearization algorithm These specifications are for one year while operation of the device 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 10 Resistance values greater than 660 2 cannot be measured by the device in the RTD mode The 660 Q resistance limit includes the total resistance across the current excitation Ix pins which is the sum of the RTD resistance and the lead resistances 22 USB TEMP AI User s Guide Specifications Note 11 For accurate three wire compensation the individual lead resistances connected to the Ix pins must be of equal ohmic value To ensure this use connection leads of equal lengths Thermistor measurement accuracy TOx T3x Table 7 Thermistor measurement accuracy specifications Ix 10 pA All specifications are Thermistor Sensor Accuracy error Accuracy error Tempco temperature range maximum typical C C C C 2252 Q 40 C 0 001 0 0007 0 001 0 C 0 021 0 008 0 001
8. 07 We hereby declare that the equipment specified conforms to the above Directives and Standards Hoe 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 mccdag com www mccdag com
9. 2 sensor common 41 DIO7 DIO channel 7 16 IT23 T2 T3 2 sensor common 42 DIO6 DIO channel 6 17 T3H T3 sensor input 43 DIO5 DIO channel 5 18 T3L T3 sensor input 44 DIO4 DIO channel 4 19 GND Ground 45 DIO3 DIO channel 3 20 12 T2 T3 current excitation return 46 DIO2 DIO channel 2 21 5V 5V output 47 DIO1 DIO chamnel 1 22 GND Ground 48 DIOO DIO channel 0 23 NC No connection 49 GND Ground 24 NC No connection 50 NC No connection 25 NC No connection 51 NC No connection 26 NC No connection 52 NC No connection 28 C Declaration of Conformity Manufacturer Measurement Computing Corporation Address 10 Commerce Way Suite 1008 Norton MA 02766 USA Category Electrical equipment for measurement control and laboratory use Measurement Computing Corporation declares under sole responsibility that the product USB TEMP AI EU EMC Directive 89 336 EEC Electromagnetic Compatibility EN 61326 1997 Amendment 1 1998 Emissions Group 1 Class A EN 55011 1990 CISPR 11 Radiated and Conducted emissions Immunity EN61326 Annex A JEC 61000 4 2 1995 Electrostatic Discharge immunity Criteria C JEC 61000 4 3 1995 Radiated Electromagnetic Field immunity Criteria A JEC 61000 4 8 1994 Power frequency magnetic field immunity Criteria A Declaration of Conformity based on tests conducted by Chomerics Test Services Woburn MA 01801 USA in July 2007 Test records are outlined in Chomerics Test Report EMI4833
10. 30 minutes before calibrating This warm up time minimizes thermal drift and achieves the specified rated accuracy of measurements Chapter 3 Signal I O Connections Screw terminal pinout The device screw terminals are identified in Figure 2 Between screw terminals 10 and 11 is the integrated CJC sensor used for thermocouple measurements TO T1 current excitation source 11 1 8 8 GND Ground No connection NC 2 8 9S V3L V3 voltage input TO sensor input TH 39 98 V3H V3 voltage input TO sensor input ToL 49 8 GND Ground TO T1 4 wire 2 sensor common awor 5 9 8 V2L V2voltage input TO T1 2 sensor common IT01 6 MO 8 V2H V2 voltage input T1 sensor input mu 07 19 8 GND Ground T1 sensor input TL 8 WO 8 viL V1 voltage input Ground ceno 9 9 8 V1H V1 voltage input TO T1 current excitation return m 10 8 8 GND Ground CJC sensor _ T2 T3 current excitation source 12 11 8 8 VOL VO voltage input No connection NC 12 o 8 VOH VO voltage input T2 sensor input T2H 13 o 8 GND Ground T2 sensor input T2L 14 8 8 CTR Counter input T2 T3 4 wire 2 sensor common 4w23 15 MO 8 DIO7 DIO channel 7 T2 T3 2 sensor common IT23 16 MO 8 DIO6 DIO channel 6 T3 sensor input T3H 17 MO 8 DIOS DIO channel 5 T3 sensor input T3 18 MO 8 DIO4 DIO channel 4 Ground GND 19 9 8 DIO3 DIO channel 3 T2 T3 current excitation return 12 20 O 98 DIO2 DIO channel 2 Power output 5V 21 S 8 DIO1 DIO channe
11. 5 or equivalent You can connect a different category of sensor to each temperature channel pair but you cannot mix sensor categories between the channels that constitute a channel pair You can however mix thermocouple types within channel pairs Each voltage input channel is software configurable for differential or single ended mode The voltage input range is software programmable for 10 V 5 V 2 5 V 1 25 V The USB TEMP AI provides a integrated cold junction compensation CJC sensor for thermocouple measurements and built in current excitation sources for resistive sensor measurements An open thermocouple detection feature lets you detect a broken thermocouple An on board microprocessor automatically linearizes the measurement data according to the sensor category The USB TEMP AI features eight independent temperature alarms Each alarm controls an associated digital T 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 The USB TEMP AlI 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 USB TEMP AI is fully software calibrated USB TEMP
12. 50 C 0 263 0 130 0 001 120 C 3 473 1 750 0 001 5000 Q 35 C 0 001 0 0006 0 001 0 C 0 009 0 004 0 001 50 C 0 115 0 049 0 001 120 C 1 535 0 658 0 001 10000 Q 25 C 0 001 0 0005 0 001 0 C 0 005 0 002 0 001 50 C 0 060 0 028 0 001 120 C 0 771 0 328 0 001 30000 Q 10 C 0 001 0 0005 0 001 0 C 0 002 0 001 0 001 50 C 0 019 0 009 0 001 120 C 0 267 0 128 0 001 Note 12 Error shown does not include errors of the sensor itself The sensor linearization is performed using a Steinhart Hart linearization algorithm The accuracy and tempco specifications include the accuracy of the Callendar Van Dusen linearization algorithm These specifications are for one year while operation is between 15 C and 35 C The specification does not include lead resistance errors for 2 wire thermistor connections Contact your sensor supplier for details on the actual sensor error limitations Total thermistor resistance on any given channel pair must not exceed 180 kQ Typical resistance values at various temperatures for supported thermistors are shown in Table 8 Table 8 Typical thermistor resistance measurement range Temp C 2252 Q 3000 Q 5 kQ 10 kQ 30 kQ thermistor thermistor thermistor thermistor thermistor 40 76 KQ 101 kQ 168 kQ 240 KQ Note 13 885 KQ Note 13 35 55 kQ 73 KQ 121 kQ 179 kQ 649 KQ Note 13 30 40 kQ 53 kQ 88 kQ 135 kQ 481 kQ Note 13 25 29 kQ 39 kQ 65 kQ 103 kQ
13. AI User s Guide Introducing the USB TEMP AI Functional block diagram USB TEMP AI functions are illustrated in the block diagram shown here 5V 5V Power DIO 1 channel 1 32 bit T 24 _ _ E z o aom D mx E 5 Fa 175 USB 2 0 ME Isolated i Isolator Micro 24 bit A D Microcontroller 12 T3 gt I I po Temp CJC ls 1 sensor TO T3 Isolated 12 5V DC DC 12 14 24 bit A D mi VO V1 gt i iy i 4 E E I 5 _ 24 bit A D a Me V2 V3 gt 3 l Event Counter I I I 500 V Isolation Barrier Figure 1 Functional block diagram Connecting a USB TEMP AI to your computer is easy Installing a data acquisition device has never been easier The USB TEMP AI 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 USB TEMP AI No third party device driver is required The USB TEMP AI is plug and play There are no jumpers to position DIP switches to set or interrupts to configure You can connect the USB TEMP AI 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
14. Activity top and Power bottom 2 Screw terminal pins 27 to52 4 USB connector Figure 12 External component locations Screw terminals Use the screw terminals for connecting temperature sensors and digital I O lines These terminals also provide ground and power output connections Refer to the Error Reference source not found chapter for screw erminal descriptions USB connector The USB connector provides 5V power and communication No external power supply is required LEDs USB TEMP AI has two LEDs Activity and Power The Activity LED top blinks when data is transferred The Power LED bottom turns on when the device is receiving power from the USB cable 18 Specifications All specifications are subject to change without notice Typical for 25 C unless otherwise specified All specifications apply to all temperature and voltage input channels unless otherwise specified Specifications in italic text are guaranteed by design Analog input Chapter 5 Table 1 Generic analog input specifications Parameter Conditions Specification A D converter type TOx to T3x VOx toV3x AD42_321 Dual 24 bit Sigma Delta Number of channels Voltage input VOx toV3x 4 differential 4 single ended Temperature input TOx toT3x 4 differential Input isolation 500 VDC minimum between field wiring and USB interface Channel configuration TOx toT3x Temperature input So
15. B TEMP AI User s Guide Specifications Note 3 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 Note 4 EEPROM The factory default configuration is Disabled The Disabled mode disconnects the temperature and voltage inputs from the terminal blocks and internally connects ground GND to all of the A D inputs This mode also disables each of the current excitation sources Compatible sensors TOx T3x Table 3 Compatible sensor type specifications Parameter Conditions Thermocouple J 210 C to 1200 C K 270 C to 1372 C 50 C to 1768 C 50 C to 1768 C 270 C to 400 C 270 C to 1300 C E 270 C to 1000 C B 0 C to 1820 C RTD 100 Q PT DIN 43760 0 00385 ohms ohm C 100 Q PT SAMA 0 003911 ohms ohm C 100 Q PT ITS 90 IEC75 1 0 0038505 ohms ohm C Thermistor Standard 2 252 Q through 30 000 Q Semiconductor IC LM35 TMP35 or equivalent Accuracy Thermocouple measurement accuracy TOx T3x Table 4 Thermocouple accuracy specifications including CJC measurement error All specifications are
16. 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 Notice Measurement 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 in injury 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 of people HM USB TEMP Al docx 2 Table of Contents Preface About this User s Guide oonnnnicnnonninacnnancananann narran 5 What you will learn from this user s guide ooooooonnnnnccnocnnonoconoconocononononnnonnconn nono nono nnnn none cn nono nono nero conocio nn nrncrnnnnnnons 5 Conventions in this user s guide Where to find more information Chapter 1 Introducing the USB TEMP Al ssssnnnsnunnnunnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnunnnnnnnnnnnnnn
17. P AI User s Guide Installing the USB TEMP AI Configuring the hardware All hardware configuration options on the USB TEMP AI are programmable with software Use InstaCal to set the sensor type for each temperature channel the range and input configuration of each voltage channel and the alarm conditions Any channel you don t intend to use should be left disabled The configurable options dynamically update according to the selected sensor category Configuration options are stored on the USB TEMP AI s isolated microcontroller in EEPROM which is non volatile memory on the USB TEMP AI 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 USB TEMP AI 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 analog RTD or thermistor measurements this warm up time is also required to stabilize the internal current reference Calibrating the USB TEMP AI The USB TEMP AI is fully calibrated via software InstaCal prompts you to run its calibration utility when you change from one sensor category to another Allow the USB TEMP AI to operate for at least
18. Phone 508 946 5100 and follow the instructions for reaching Tech Support Fax 508 946 9500 to the attention of Tech Support Email techsupportmccdag 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 is available in PDF at www mccdaq com PDFmanuals DAQ Software Quick Start pdf Installing the hardware To connect the USB TEMP AI 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 USB TEMP AI When you connect the USB TEMP AI for the first time a notification message opens as the USB TEMP AI is detected When the message closes the installation is complete The upper LED Activity blinks when initially connected and then stays on The lower LED USB turns on to indicate that communication is established between the device and computer If the USB LED turns off If the LED is lit but then turns off the computer has lost communication with the USB TEMP AI 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 TEM
19. Storage temperature range 40 C to 85 C max Humidity 0 to 90 non condensing max 27 USB TEMP AI User s Guide Specifications Mechanical Table 24 Mechanical specifications Dimensions L x W x H 128 52 x 88 39 x 35 56 mm 5 06 x 3 48 x 1 43 ft User connection length 3 m 9 84 ft max Screw terminal connector Table 25 Screw terminal connector specifications Connector type Screw terminal Wire gauge range 16 AWG to 30 AWG Table 26 Screw terminal pinout Pin Signal Name Pin Description Pin Signal Name Pin Description 1 1 TO T1 current excitation source 27 GND Ground 2 NC No connection 28 V3L V3 voltage input 3 TOH TO sensor input 29 V3H V3 voltage input 4 TOL TO sensor input 30 GND Ground 5 4WO01 TO T1 4 wire 2 sensor common 31 V2L V2 voltage input 6 IT01 TO T1 2 sensor common 32 V2H V2 voltage input 7 T1H T1 sensor input 33 GND Ground 8 TiL T1 sensor input 34 VIL V1 voltage input 9 GND Ground 35 V1H V1 voltage input 10 l1 TO T1 current excitation return 36 GND Ground CJC sensor 11 12 T2 T3 current excitation source 37 VOL VO voltage input 12 NC 38 VOH VO voltage input 13 T2H T2 sensor input 39 GND Ground 14 T2L T2 sensor input 40 CTR Counter Input 15 4W23 T2 T3 4 wire
20. USB TEMP AI Temperature and Voltage Measurement User s Guide Document Revision 6 March 2013 Vi N FA MEASUREMENT O Copyright 2013 4 E Las COMPUTING Your new Measurement Computing product comes with a fantastic extra Management committed to your satisfaction Thank you for choosing a Measurement Computing product and congratulations You own the finest and you can now enjoy the protection of the most comprehensive warranties and unmatched phone tech support It s the embodiment of our mission To provide data acquisition hardware and software that will save time and save money Simple installations minimize the time between setting up your system and actually making measurements We offer quick and simple access to outstanding live FREE technical support to help integrate MCC products into a DAQ system Limited Lifetime Warranty Most MCC products are covered by a limited lifetime warranty against defects in materials or workmanship for the life of the product to the original purchaser unless otherwise noted Any products found to be defective in material or workmanship will be repaired replaced with same or similar device or refunded at MCC s discretion For specific information please refer to the terms and conditions of sale Harsh Environment Program Any Measurement Computing product that is damaged due to misuse or any reason may be eligible for replacement with the same or similar device for 50 of the current l
21. ads TRUE 1 If you move the switch to GND DIOO reads FALSE 0 DIOO a nb I Figure 11 Schematic showing switch detection by digital channel DIOO Caution All ground pins on the USB TEMP AI pins 9 19 22 27 30 33 36 39 49 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 DAQ Signal Connections available on our website at www mccdaq com signals signals pdf Configuring the DIO channels to generate alarms The USB TEMP AI features eight independent temperature alarms All alarm options are software configurable When a digital bit is configured as an alarm that bit will be configured as an output on the next power cycle and assume 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 the temperature input channels You set up the temperature conditions to activate an alarm and the output state of the channel active high or low when activated When an alarm is activated its associated DIO channel is driven to the output state specified The alarm configurations ar
22. any conductive surfaces that may be referenced to earth ground Ground terminals GND The nine ground terminals GND provide a common ground for the input channels and DIO bits and are isolated 500 VDC from the USB GND 11 USB TEMP AI User s Guide Signal I O Connections Power output 5V The 5V output terminal is isolated 500 VDC from the USB 5V Caution The 5V terminal is an output terminal Do not connect to an external power supply or you may damage the USB TEMP AI and possibly the computer CJC sensor The USB TEMP AI has one built in high resolution temperature sensor The CJC sensor measures the ambient temperature at the terminal block so that the cold junction voltage can be calculated 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 USB TEMP AI makes fully differential thermocouple measurements without requiring ground referencing resistors A 32 bit floating point value in either a voltage or temperature format is returned by software An open thermocouple detection OTD feature is available for each thermocouple input This feature automatically detects an open or broken thermocouple Use InstaCal to select the thermocouple type J K R S T N E and B on one or more sensor input channels to connect the thermocouple Wiring c
23. configuration The easiest way to connect an RTD sensor or thermistor to the USB TEMP AI 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 Q 0 5 Q each lead to a 100 Q 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 HF OOO T O gt fF O T L O O O O THL O GND Figure 4 Two wire single RTD or thermistor sensor measurement configuration When you select a two wire single sensor configuration with InstaCal connections to T H and T L are made internally 13 USB TEMP AI User s Guide Signal I O Connections Two wire two sensor A two wire two sensor measurement configuration is shown in Figure 5 EHI Oy ZE E OO I TAL IT O O O O 4w O THL O GND Figure 5 Two wire two RTD or thermistor sensors measurement configuration When you select a two wire two sensor configuration with In
24. d up to 5 V via 47 K resistors default Contact MCC factory for pull down to ground GND capability Digital I O transfer rate software paced Digital input 50 port reads or single bit reads per second typ Digital output 100 port writes or single bit writes per second typ 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 0 7 V max IOL 2 5 mA max Output high voltage 3 8 V min IOH 2 5 mA max 25 USB TEMP AI User s Guide Specifications Note 19 All ground pins are common and are isolated from earth ground If a connection is made to earth ground when using both 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 Counter Table 16 CTR I O specifications Parameter Specification Pin name CTR Number of channels 1 Resolution 32 bits Counter type Event counter Input type TTL rising edge triggered Input source CTR screw terminal Counter read writes rates Counter read System dependent 33 to 1000 reads per second software paced Counter write System dependent 33 to 1000 reads per second Schmidt trigger hysteresis 20 mV to 100 mV Input leakage current 1 0 uA typ Input frequency 1 MHz max High
25. e thermocouples must not be connected to any conductive surfaces that may be referenced to earth ground Note 17 Unused voltage inputs should not be left floating These inputs should be placed in the Disabled mode or connected to GND Table 10 Accuracy components All values are Range Gain error Offset INL error Gain Offset Temperature of reading error of range Temperature Coefficient uV Coefficient uV C ppm C 10 V 0 0246 16 75 0 0015 3 68 0 42 5 V 0 0246 16 75 0 0015 3 68 0 42 2 5 V 0 0246 16 75 0 0015 3 68 0 42 1 25 V 0 0246 16 75 0 0015 3 68 0 42 Table 11 Noise performance specifications Range Peak to peak noise RMS noise Noise Free resolution uV Vrms bits 10 V 41 13 6 23 19 09 5 V 30 85 4 67 18 51 2 5 V 17 14 2 60 18 36 1 25 V 11 14 1 69 17 98 Table 11 summarizes the noise performance for the device Noise distribution is determined by gathering 1000 samples with inputs tied to ground at the user connector Samples are gathered at the maximum specified sample rate of 2 S s Settling time VOx V3x Table 12 Settling time specifications Range Accuracy 0 0004 seconds 10 V 15 0 5 V 0 40 2 5 V 0 40 1 25 V 0 40 24 USB TEMP AI User s Guide Specifications Settling time is defined as the time required for a channel to settle within a specified accuracy in respo
26. e stored in non volatile memory and are loaded on power up The temperature alarms function both in data logging mode and while attached to the USB port on a computer 16 Captor 4 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 USB TEMP AI hardware level shifts the thermocouple s output voltage into the A D s common mode input range by applying 2 5 V to the thermocouple s low side at the C L input Always connect thermocouple sensors to the USB TEMP AI 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 USB TEMP AI terminal blocks produce two additional thermocouple junctions This junction creates a small voltage error term which must be removed from the overall sensor measurement using a cold junction compensation technique The measured voltage includes both the thermocouple voltage and the cold junction voltage To compensate for the additional cold junction voltage the USB TEMP AI subtracts the cold junction voltage from the thermocouple voltage The USB TEMP AI has one high resolution temperature sensor integrated into the desig
27. evice such that they are floating with respect to GND pins 9 19 22 27 30 33 36 39 49 The device GND pins are isolated from earth ground You can connect thermocouple sensors to voltages referenced to earth ground as long as the isolation between the GND pins and earth ground is maintained Note 7 When thermocouples are attached to conductive surfaces the voltage differential between multiple thermocouples must remain within 1 4 V For best results we recommend using insulated or ungrounded thermocouples when possible Semiconductor sensor measurement accuracy TOx T3x Table 5 Semiconductor sensor accuracy specifications Sensor type Temperature Range Accuracy Error maximum LM35 TMP35 or 40 C to 150 C 0 50 C equivalent Note 8 Error shown does not include errors of the sensor itself These specifications are for one year while operation of the device is between 15 C and 35 C Contact your sensor supplier for details on the actual sensor error limitations RTD measurement accuracy TOx T3x Table 6 RTD measurement accuracy specifications 210 YA All specifications are RTD Sensor temperature Accuracy error C Accuracy error C Tempco range C maximum typical C C PT100 DIN 200 2 913 2 784 0 001 US or ITS 90 _150 1 201 1 070 0 001 100 0 482 0 349 0 001 0 0 261 0 124 0 001 100 0 269 0 127 0 001 300 0 287 0 136 0 001 600
28. ftware programmable to match sensor type VOx toV3x Voltage input Analog input modes Power up and reset state Factory default configuration is Disabled mode Once configured each channel reverts to the mode previously set by the user Single ended Vx_H inputs are connected directly to their screw terminal pins Vx_L inputs are disconnected from their screw terminal pins and internally connected to GND Differential Vx_H and Vx_L inputs are connected directly to their screw terminal pins Tx_H and Tx_L inputs are connected directly to their screw terminal pins Input ranges Thermocouple TOx toT3x 0 080 V RTD TOx toT3x 0 to 0 5 V Thermistor TOx toT3x 0to2 V Semiconductor sensor TOx toT3x 0 to 2 5 V Voltage VOx toV3x 10 V 5 V 2 5 V 1 25 V software selectable Absolute maximum input voltage TOx to T3x relative to GND pins 9 19 22 27 30 33 36 39 49 25 V max power on 40 V max power off VOx to V3x relative to GND pins 9 19 22 27 30 33 36 39 49 25 V max power on 15 V max power off Input impedance TOx to T3x 5 GQ power on 1 MQ power off Input leakage current VOx to V3x 10 GQ power on 2 49 kQ power off TOx to T3x with open thermocouple 30 nA max detect disabled TOx to T3x with open thermocouple 105 nA max detect enabled VOx to V3x 5 nA typ 25 nA max Input bandwidth
29. g Corporation with specific questions Knowledgebase kb mccdag 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 mccdag com Chapter 1 Introducing the USB TEMP AI The USB TEMP ATI is a USB 2 0 full speed temperature measurement module that is supported under popular Microsoft Windows operating systems The USB TEMP AI is fully compatible with both USB 1 1 and USB 2 0 ports The USB TEMP AI provides eight analog input channels that are configured as four differential temperature inputs and four differential or single ended voltage inputs A 24 bit analog to digital A D converter is provided for each pair of analog inputs 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 The temperature input channels are configured as two channel pairs that accept temperature sensor type inputs You can take measurements from four sensor categories The sensor category is software programmable for each channel pair Thermocouple types J K R S T N E and B Resistance temperature detectors RTDs 2 3 or 4 wire measurements of 100 Q platinum RTDs Thermistors 2 3 or 4 wire measurements Semiconductor temperature sensors LM35 TMP3
30. h a single sensor per channel pair 2 differential channels 4 wire input configuration with a single sensor per channel 2 differential channels pair 4 wire input configuration with two sensors per channel pair 4 differential channels VOx V3x Disabled All voltage input channels are disconnected from screw See Note 4 terminals and internally connected to GND VOx V3x Differential 4 differential channels Note 2 VOx V3x Single ended 4 single ended channels Note 1 Internally the device has four dual channel fully differential A Ds providing a total of eight input channels The temperature input channels are configured as two channel pairs with TOx T1x and T2x T3x accepting temperature sensor type inputs This channel pairing requires TOx T1x and T2x T3x to 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 temperature channel 0 and a type T thermocouple on temperature channel 1 is valid Note 2 The voltage input channels VOx V1x V2x and V3x are not configured as channel pairs Therefore each channel can be configured independently When connecting differential inputs to floating input sources you must provide a DC return path from each differential input to ground To do this simply connect a resistor from each of the differential inputs to GND A value of approximately 1 MQ can be used for most applications 20 US
31. ist price I O boards face some harsh environments some harsher than the boards are designed to withstand Contact MCC to determine your product s eligibility for this program 30 Day Money Back Guarantee Any Measurement Computing Corporation product may be returned within 30 days of purchase for a full refund of the price paid for the product being returned If you are not satisfied or chose the wrong product by mistake you do not have to keep it These warranties are in lieu of all other warranties expressed or implied including any implied warranty of merchantability or fitness for a particular application The remedies provided herein are the buyer s sole and exclusive remedies Neither Measurement Computing Corporation nor its employees shall be liable for any direct or indirect special incidental or consequential damage arising from the use of its products even if Measurement Computing Corporation has been notified in advance of the possibility of such damages Trademark and Copyright Information Measurement Computing Corporation InstaCal Universal Library and the Measurement Computing logo are either trademarks or registered trademarks of Measurement Computing Corporation Refer to the Copyrights amp Trademarks section on mecdag 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 2013 Measurement
32. l 1 Ground GND 22 8 8 DIOO DIO channel 0 No connection Nc 23 O 8 GND Ground No connection NC 24 8 98 NC No connection No connection NC 25 98 8 NC No connection No connection Nc 26 O 8 NC No connection Figure 2 USB TEMP AI screw terminal pin numbers Use 16 AWG to 30 AWG wire for your signal connections Tighten screw terminal connections When making connections to the screw terminals be sure to tighten the screw until tight Simply touching the top of the screw terminal is not sufficient to make a proper connection Voltage input terminals VOH VOL to V3H V3L You can connect up to four voltage inputs to the voltage channels VOH VOL to V3H V3L The input range is software programmable for 10 V 5 V 2 5 V or 1 25 V Each voltage channel is software configurable for differential or single ended mode When connecting differential inputs to floating input sources you must provide a DC return path from each differential input to ground One way to do this is to connect a resistor from one side of each of the differential inputs to GND A value of approximately 100 kQ can be used for most applications Caution All ground pins are common and 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
33. mall 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 USB TEMP AI features two built in current excitation sources I1 and 12 for measuring resistive type sensors Each current excitation terminal is dedicated to one channel pair The USB TEMP AI makes two three and four wire measurements of RTDs 100 Q 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 cannot be measured by the USB TEMP AI in the RTD mode The 660 Q 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 180 KQ cannot be measured by the USB TEMP AI in the thermistor mode The 180 kQ 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
34. n The CJC sensor measures the average temperature at the terminal block 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 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 USB TEMP AI is equipped with 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 RTD and the
35. n 21 self powered hub Note 21 Isolation Measurement system to PC 500 VDC min Note 21 This is the total current requirement for the device which includes up to 10 mA for the status LED USB specifications Table 21 USB specifications USB device type USB 2 0 full speed Device compatibility USB 1 1 USB 2 0 Device power capability Self powered USB cable type A B cable UL type AWM 2725 or equivalent min 24 AWG VBUS GND min 28 AWG D D USB cable length 3 meters max Current excitation outputs lx TOx T3x Table 22 Current excitation output specifications Parameter Specification Configuration 2 dedicated pairs 11 TOx T1x 12 T2x T3x Current excitation output Thermistor 10 pA ranges RTD 210 pA Tolerance 5 0 Drift 200 ppm C Line regulation 2 1 ppm V max Load regulation 0 3 ppm V Output compliance voltage 3 90 V max relative to GND pins 0 03 V min Note 22 The device has two current excitation outputs with 11 dedicated to the TOx T1x analog inputs and 12 dedicated to T2x T3x The excitation output currents should always be used in this dedicated configuration Note 23 The current excitation outputs are automatically configured based on the sensor thermistor or RTD selected Environmental Table 23 Environmental specifications Operating temperature range 0 C to 55 C max
36. nannanos Semiconductor sensor measurement accuracy TOx T3x RID measurement accuracy TOX SK ena e ae iaa aa era S er Sa O E rE e EAS r E EN EE ENESTE AET Thermistor measurement accuracy TOx T3x Absolute Accuracy VOx V3x Settling time VOx V3X Analog input calibration Throughput rate Digital input output Counter USB specifications Current excitation outputs Ix TOx T3x Environmental Mechanical Screw terminal connector Declaration Of Conformity rss cacccscccecesevess aii AR id dica end daa 29 Preface About this User s Guide What you will learn from this user s guide This user s guide describes the Measurement Computing USB TEMP AI data acquisition device and lists device specifications Conventions in this user s guide For more information Text presented in a box signifies additional information related to the subject matter Caution Shaded caution statements present information to help you avoid injuring yourself and others damaging your hardware or losing your data bold text Bold text is used for the names of objects on a screen such as buttons text boxes and check boxes italic text Italic text is used for the names of manuals and help topic titles and to emphasize a word or phrase Where to find more information Additional information about USB TEMP hardware is available on our website at www mccdag com You can also contact Measurement Computin
37. nnnn ennnen 6 Functional A sonne en eaii NO 7 Connecting a USB TEMP AI to your computer is easy essseessseeeseeesseesesresresteersseerrssertenestentesrertnserrrnsesrreresee 7 Chapter 2 Installing the USB TEMP AI wwi sc cceccesesecececetssstesceecececets sctedacecececetsnseesdencecececd esters dad ad 8 What comes INSI 8 Hardware Documentation Unpaid la 8 Installing the software Installing the hardware Configuring the hard A TN 9 Calibrating the USB TEMP AUT coovitocdoonnc ota coa a ES r OEE ERE eh EE E NO SaR AEE KITES Epin RES tE 9 Chapter 3 Signal VO CONMCCUONS iii ii SA A bes heh ese oeoa re E oie sche EEVEE E rakoen EEr EE TOENE SESE EMS ENE DEES Voltage input terminals VOH VOL to V3H V3L Sensor input terminals TOH TOL to T3H T3L ccceccsseecseseeeceeeceecesececeesecceesecseeeaeceeesecesecseeeaeesecesecseeeseeeeeaeceeeaeenes Current excitation output terminals 11 and 412 oo ee eecececsccecceseceseeseceeeesececeeseceeeesecesecseceseceeeesecseceaeseeeeseseeeeaeseeseneeee Four wire two sensor common terminals 4W01 and 4W23 Sensor common terminals ITOL anid TI23 wi iiss ii si A EAEE EN saeesv ed cock ondaa biie Digital terminals DIO0 to DIO Di o RE Counter terminal CTR oooooocccinn Ground terminals GND Power output 5V Gi Ga ihe ii EE ECT ise ie aaa Thermocouiple COnme ctoms gt i c3 i s3 sai ckatioset ccuanse sn ohah Sei E AERE EE ch sv sacoatbeadyco
38. nse to a full scale FS step input Analog input calibration Table 13 Analog input calibration specifications Parameter Specifications Recommended 30 minutes min warm up time Calibration Firmware calibration Calibration interval 1 year Calibration 10 000 V 5 mV max Actual measured values stored in EEPROM reference Tempco 5 ppm C max Long term stability 30 ppm 1000 h Throughput rate Table 14 Throughput rate specifications Number of Input Maximum throughput Channels 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 18 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 voltage temperature data is provided by the USB unitis approximately 0 4 seconds Digital input output Table 15 Digital input output specifications Parameter Specification Digital type 5V CMOS Number of I O 8 DIOO through DIO Configuration Independently configured for input or output Power on reset is input mode unless bit is configured for alarm Pull up pull down configuration All pins pulle
39. onfiguration Connect the thermocouple to the USB TEMP AI using a differential configuration as shown in Figure 3 Syr O L O Z a QRESER EG x J Figure 3 Typical thermocouple connection i The USB TEMP AI GND pins are isolated from earth ground You can connect thermocouple sensors to voltages referenced to earth ground as long as the isolation between the GND pins and earth ground is maintained When thermocouples are attached to conductive surfaces the voltage differential between multiple thermocouples must remain within 1 4 V For best results we recommend the use of insulated or ungrounded thermocouples when possible Maximum input voltage between analog input and ground The absolute maximum input voltage between an analog input and the isolated GND pins is 25 VDC when the USB TEMP AI is powered on and 40 VDC when the USB TEMP AI 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 12 USB TEMP AI User s Guide Signal I O Connections 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 s
40. pulse width 500 nS min Low pulse width 500 ns min Input high voltage 4 0 V min 5 5 V absolute max Input low voltage 1 0 V max 0 5 V absolute min Note 20 All ground pins are common and are isolated from earth ground If a connection is made to earth ground with both the counter CTR 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 17 Memory specifications Parameter Specification EEPROM 1 024 bytes isolated micro reserved for sensor configuration 256 bytes USB micro for external application use Microcontroller Table 18 Microcontroller specifications Parameter Specification Type Two high performance 8 bit RISC microcontrollers USB 5V voltage Table 19 USB 5V voltage specifications Parameter Specification USB 5V VBUS input voltage 4 75 V min to 5 25 V max range 26 USB TEMP AI User s Guide Specifications Power Table 20 Power specifications Parameter Conditions Specification Supply current USB enumeration lt 100 mA Supply current Quiescent mode with all inputs 270 mA typ Note 21 configured for Disabled mode User 5V output voltage range 4 9 V min to 5 1 V max terminal block pin 21 User 5V output current Bus powered and connected to a 5 mA max terminal block pi
41. r semiconductor sensors can be accurate inexpensive and easy to interface with other electronics for display and control The USB TEMP AI makes high resolution measurements of semiconductor sensors and returns a 32 bit floating point value in either voltage or temperature Use InstaCal to select the sensor type LM35 TMP35 or equivalent and the sensor input channel to connect the sensor 15 USB TEMP AI User s Guide Signal I O Connections Wiring configuration Connect the semiconductor sensor to the USB TEMP AI using a single ended configuration as shown in Figure 10 The device provides 5V and GND pins for powering the sensor E Q ILI Li gt a QE sE FEZI io zee fe PO n O E 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 DIOO 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 kQ 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 USB TEMP AI digital I O terminals to detect the state of a TTL compatible device Refer to the schematic shown in Figure 11 If you set the switch to the 5V input DIOO re
42. rmistor 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 USB TEMP AI 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 Ix source The value of the Ix source is stored in local memory Once the resistance value is calculated the value is linearized in order to convert it to a temperature value The measurement is returned by software as a 32 bit floating point value in either temperature or resistance 17 USB TEMP AI User s Guide Functional Details 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 External components The USB 5203 has the following external components as shown in Figure 12 1 Screw terminal pins 1 to 26 3 LEDs
43. sistance 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 USB TEMP AI with either a single sensor per channel or two sensors per channel pair 14 USB TEMP AI User s Guide Signal I O Connections Four wire single sensor A four wire single sensor connected to the first channel of a channel pair is shown in Figure 7 Sigan l ES sE F E EE O F E 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 Lai E La HH HH REIYFF OOOWOOOD S st E GND O O O 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 Semiconductor sensor measurements Semiconductor sensors are suitable over a range of approximately 40 C to 125 C where an accuracy of 2 C is adequate The temperature measurement range of a semiconductor sensor is small when compared to thermocouples and RTDs Howeve
44. staCal connections to T H first sensor and T H T 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 TEENA 2000000000 Figure 6 Three wire RTD or thermistor sensor measurement configuration O T H THL O IT O T H O THL GND O When you select a three wire sensor configuration with InstaCal the USB TEMP AI measures the lead resistance on the first channel T H T L and measures the sensor itself using the second channel T H T L This configuration compensates for any lead wire resistance and temperature change in lead wire resistance Connections to T H for the first channel and T H T L of the second channel are made internally Three wire compensation For accurate three wire compensation the individual lead resistances connected to the I pins must be of equal resistance value Four wire configuration With a four wire configuration connect two sets of sense excitation wires at each end of the RTD or thermistor sensor This configuration completely compensates for any lead wire resistance and temperature change in lead wire re
45. vonte eustbubdebenassentonvetvanepoetes Wiring configurati Oris iii IS O cod Fa Ea CRON NEL A as RTD and thermistor connections ii A ceda rocio ias TOO WITE CONAN edita Three wire configuration MS AN Semiconductor Sensor measurements oococcccccncnnnnnnnnnonononononononononononononononononononononononononononononononononononononononononones Wiring configuration Digital O conmections io cd Configuring the DIO channels to generate alarms oooonnonccncnnococnnnnoncnnnanononoconcnnnononononononnnon cnn onn cnn on none nan naaa cnn canon nane ra nnncnans Chapter 4 Functional Details a a a a aaa aaaeei aaa nana 17 Th rmoco plemeas rements eiieeii eT s EEEN EE EE E AE E EE EE EENE KE EESE seeds 17 Cold junction compensation CIC yssen te e A A REENEN E ENEEK 17 Data Tim Cari Zach On A eee TEES 17 Open thermocouple detection OTD ozsa Aaa 17 RID and thermistor MeasureMents ese 2 05500 vsccseetsesievescseessacesbevecsononssaens T E E E 17 Data Mme arizati O NN NN 18 USB TEMP AI User s Guide Extemal components nenas id 18 Screw terminals ccccceee USB connector Chapter 5 SPeEcifi Cations ui A dea eae eerie li 19 Analog input Channel config rations cidcid red noi iii ados cidad Compatible sensors TOx T3x ACCUILACY cate OR O NU Thermocouple measurement accuracy TOX T3X oooooccnccconananiononninnonancnonannnnonancanennnnononnnnonononennnnnnonnononennnnnnonnananennnnu

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