Measurement Computing TC-32 User manual

TC-32
32-Channel Thermocouple Input USB/Ethernet DAQ Device
User's Guide
Document Revision 2
November 2015
© Copyright 2015
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2
HM TC-32.docx
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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.........................................................................................................................5
Chapter 1
Introducing the TC-32...........................................................................................................................6
Ethernet interface................................................................................................................................................6
USB interface .....................................................................................................................................................6
Functional block diagram...................................................................................................................................7
Chapter 2
Installing the TC-32...............................................................................................................................8
Unpacking...........................................................................................................................................................8
Installing the software ........................................................................................................................................8
Connecting the external power adapter ..............................................................................................................8
Installing the hardware .......................................................................................................................................8
Installing on USB.............................................................................................................................................................. 8
Installing on Ethernet........................................................................................................................................................ 8
IP address settings............................................................................................................................................................. 9
Setting up the TC-32 for communication across networks.................................................................................9
Calibrating the hardware...................................................................................................................................10
Factory calibration...........................................................................................................................................................10
Field calibration...............................................................................................................................................................10
Updating firmware............................................................................................................................................10
Restoring factory default network settings.......................................................................................................10
Chapter 3
Functional Details ...............................................................................................................................11
External components ........................................................................................................................................11
USB connector.................................................................................................................................................................11
Ethernet connector...........................................................................................................................................................11
External power connector................................................................................................................................................11
TC input connectors, measurements, and LED................................................................................................................11
Digital I/O........................................................................................................................................................................13
LED indicators.................................................................................................................................................................14
EXPANSION connector..................................................................................................................................................15
Chassis ground connector................................................................................................................................................15
RESET button..................................................................................................................................................................15
Mechanical drawings........................................................................................................................................16
Chapter 4
Specifications......................................................................................................................................18
Thermocouple input..........................................................................................................................................18
Channel configuration ......................................................................................................................................19
Compatible thermocouple sensors....................................................................................................................19
Accuracy...........................................................................................................................................................19
Thermocouple measurement accuracy.............................................................................................................................19
Digital input/output...........................................................................................................................................20
Temperature alarms..........................................................................................................................................21
Memory ............................................................................................................................................................21
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TC-32 User's Guide
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Microcontroller.................................................................................................................................................21
Power................................................................................................................................................................21
USB ..................................................................................................................................................................22
Network............................................................................................................................................................22
Ethernet connection .........................................................................................................................................................22
Network interface ............................................................................................................................................................22
Network factory default settings......................................................................................................................................23
Network security..............................................................................................................................................................23
LED displays and the factory reset button........................................................................................................23
Environment .....................................................................................................................................................23
Mechanical .......................................................................................................................................................23
Signal I/O connectors .......................................................................................................................................24
Declaration of Conformity..................................................................................................................26
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5
Preface
About this User's Guide
What you will learn from this user's guide
This user's guide describes the Measurement Computing TC-32 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 TC-32 hardware is available on our website at www.mccdaq.com. You can also
contact Measurement Computing Corporation with specific questions.
Knowledgebase: kb.mccdaq.com
Tech support form: www.mccdaq.com/support/support_form.aspx
Email: [e-mail]
Phone: [phone] and follow the instructions for reaching Tech Support
For international customers, contact your local distributor. Refer to the International Distributors section on our
website at www.mccdaq.com/International.
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6
Chapter 1
Introducing the TC-32
The TC-32 is a dual-interface data acquisition device that provides the following features:
32 differential thermocouple (TC) inputs, expandable to 64 channels with
TC-32-EXP expansion device1
Two 24-bit ADCs (one ADC per 16 inputs)
TC channels field-to-host isolation
3 S/s per update rate
Support for type J, K, R, S, T, N, E, and B thermocouples, software-selectable per channel
One integrated cold junction compensation (CJC) sensor per TC input
Open thermocouple detection (OTD) to detect faulty TC connections
8 digital inputs, isolated from TC and host
32 digital outputs/alarms isolated from TC inputs and host
DIO connections are made to 50-pin header connector
USB 2.0 or 10/100 Ethernet interface
Powered by the included +5 V external power adapter (PS-5V2AEPS)
Ethernet interface
The TC-32 has a built-in 10/100 BASE-T auto-negotiation, high-speed communication port.
With the Ethernet interface, you can remotely access and configure your TC-32 from anywhere on the network.
Only one computer can control the TC-32 at a time.
A unique media access control (MAC) address is assigned to each device at the factory. You configure the
Ethernet connection settings through software. The network name uses the format TC-32-xxxxxx, where
xxxxxx are the lower six digits of the factory-assigned MAC address.
USB interface
The TC-32 is a USB 2.0 full-speed device that is compatible with USB 3.0 ports. The device is also compatible
with USB 1.1 ports.
140-pin ribbon cable for the EXPANSION connector is included with the TC-32-EXP.
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TC-32 User's Guide Introducing the TC-32
7
Functional block diagram
Device functions are illustrated in the block diagram shown here:
Figure 1. TC-32 functional block diagram
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8
Chapter 2
Installing the TC-32
Unpacking
As with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the board 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.
Installing the software
Refer to the MCC DAQ Software Quick Start for instructions on installing the software on the MCC DAQ CD.
Refer to the device product page on the Measurement Computing website for information about the included
and optional software supported by the TC-32.
Install the software before you install your device
The driver needed to run the TC-32 is installed with the software. Therefore, you need to install the software
package you plan to use before you install the hardware.
Connecting the external power adapter
Power to the TC-32 is provided with the 5 V external power adapter (PS-5V2AEPS). Connect the adapter cord
to the power connector on the TC-32 device, and plug the AC adapter into an electrical outlet.
The Power LED turns on when 5 V power is supplied to the TC-32. If the voltage supply is less than 4.0 V or
more than 5.75 V, the POWER LED does not turn on.
Refer to Figure 2on page 11 for the location of the Power LED.
Installing the hardware
Installing on USB
Connect the TC-32 using the cable provided to a to a USB port on a computer running Windows. Windows
finds and installs the device driver automatically, and notifies you that the device is ready to use.
Installing on Ethernet
The TC-32 requires a TCP/IP and UDP connection to a network or computer. Use the standard Ethernet cable
provided to connect the TC-32 to a 10Base-T or 100Base-TX compatible Ethernet port, hub, or switch.
When connecting the TC-32 for the first time, make sure that you connect to a local network with DHCP
enabled.
If you are unsure whether you have access to a local network or that DHCP is enabled on that network, you
should use a direct connection to a Windows PC.
It may take a minute or two to detect the device and assign the address. The green Link/activity LED on the
lower left of the Ethernet connector turns on when there is a valid Ethernet link, and blinks when network
activity is detected.
Once the TC-32 is physically connected to the local network or PC, you can run the software (InstaCal for
example) to establish a connection. If a connection cannot be established, make sure the device is using the
default configuration by following the instructions in the Restoring factory default network settings on page 10.
Once a connection is established and you can communicate to the device, you can change the configuration for
other network scenarios.
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TC-32 User's Guide Installing the TC-32
9
Configuring network settings
The following TC-32 network settings are software-selectable. Only one user at a time can connect to the TC-32
to configure network options on the device. For typical local networks, the default settings are recommended.
Address mode settings
The address mode setting determines whether the default IP parameters (IPv4 address, subnet mask, and
gateway) are assigned to the TC-32 or an auto-addressing method is used to assign these parameters.
DHCP or link-local enabled (default)
If connected to a network with a DHCP server, the service automatically assigns IP addresses to the TC-32.
If the connected network does not have a DHCP server, the address stored in the default IP address is assigned
to the TC-32.
If the TC-32 is directly connected to a Windows PC or other host that supports link-local addressing, a link-
local address is assigned to the device. A link-local address is valid only for communications between the
TC-32 and the device to which it is connected
DHCP Only
Enables configuration by a DHCP server if one is available. The TC-32 is assigned an IP address shortly after it
is powered up and attached to the network.
Link Local Only
The TC-32 is assigned a link-local IP address by the Windows PC or other host that supports link-local
addressing. A link-local address is valid only for communications between the TC-32 and the device to which it
is connected.
Static
The default IPv4 Address is manually configured on the TC-32.
IP address settings
The default settings of the following IP address are assigned to the TC-32 when automatic addressing is
disabled or not available (DHCP or Link Local for example)
IPv4 address – The IP address that is stored on the device. The default IPv4 address is 192.168.0.101.
Subnet mask – The Subnet mask that is stored on the TC-32 . The subnet mask determines the number of
bits of the IP address that is used for the host portion of the address vs. the number of bits used for the
network portion. The default subnet mask is 255.255.255.000
Gateway – The gateway IP address that is stored on the TC-32. The gateway address of the device that
bridges subnets within a network. The default gateway is 192.168.0.1
Connection code
The connection code is a number between 0 (default) and 999999999. You can change this number from its
default of 0 to prevent other users from connecting to and configuring the device. The device remains visible to
other users on the network, but connection by another user is not allowed.
Setting up the TC-32 for communication across networks
In order to communicate with the TC-32 from a computer connected to a different network – such as over the
Internet – you must change the network configuration of the network router.
In the following procedure, the TC-32 is installed on the host LAN, the computer is installed on the client LAN,
and it is assumed that you have you have successfully connected the device to a local network.
Caution! This procedure should only be performed by a network administrator or computer professional.
Incorrect settings can significantly disrupt a network.
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TC-32 User's Guide Installing the TC-32
10
1. Determine the IP address of the device. If the address was assigned by DHCP, it is recommended you
change it to a static address by setting the default address to the address assigned and setting the device
network configuration to static.
2. Configure the firewall/router to forward incoming traffic to the following ports to the IP address assigned
to the device:
oUDP:54211 (discovery)
oTCP:54211 (commands)
3. On the computer connected to the client LAN, manually enter the WAN address of the host router, and
specify the ports that were forwarded to connect to the remote TC-32.
Calibrating the hardware
Factory calibration
The Measurement Computing Manufacturing Test department performs the initial factory calibration. Return
the device to Measurement Computing Corporation when calibration is required. The recommended calibration
interval is one year.
Field calibration
The TC-32 supports field calibration. Calibrate the device using InstaCal whenever the ambient temperature
changes by more than ±10 °C from the last calibration.
The following items are required to perform field calibration on a TC-32:
a precision voltage source
a voltmeter
Each ADC (two ADCs per device) is measured at three points and a linear correction is calculated.
When prompted, enter the voltmeter reading to a precision of three decimal places.
MCC strongly recommends that you warm up the TC-32 for at least 20 minutes prior to performing field
calibration.
Updating firmware
Your DAQ device contains firmware that can be updated in the field if required. Firmware is available for
download at www.mccdaq.com/firmware.aspx. MCC recommends that you check this page periodically to see
if an update to your device firmware is available.
Restoring factory default network settings
To reset the network configuration settings to the factory default values, complete the following steps:
1. Use a ballpoint pen to press and hold in the Reset button for at least four seconds until both the Power and
Activity LEDs blink , indicating that the settings have been restored to the factory defaults.
2. Release the button so the device continues startup with the default settings. If the button is released before
the two LEDs blink, the settings are not affected and the device starts up normally.
If InstaCal is open when default settings are restored, click the Refresh Boards button on the InstaCal toolbar
to reflect the changes.
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11
Chapter 3
Functional Details
External components
TC-32 front panel components are shown in Figure 2.
1
TC input channels 0 through 31 (32 mini-jack connectors)
4
ALARM LED
2
POWER LED
5
OPEN TC LED
3
ACTIVITY
LED
Figure 2. TC-32 front panel components
TC-32 rear panel components are shown in Figure 3.
1
Factory
RESET
button
6
Chassis ground connector
2
USB connector
7
40-pin EXPANSION connector
3
ETHERNET
connector 8 Eight digital input (
DIN
) pull-up switches
4
External power (EXT DC) connector
9
32 digital output (DOUT) pull-up switches
5
Power switch (
PWR
)
10
50-pin
DIGITAL I/O
connector
Figure 3. TC-32 rear panel components
USB connector
The USB connector provides USB communication.
Ethernet connector
The E-1608 has one 10/100 BASE-T, auto-negotiation, high-speed communication port. The port connector is
an RJ-45, eight-position connector. The Ethernet port accepts CAT-5 shielded or unshielded twisted pair cable.
The maximum communication distance without using a repeater is 100 meters.
External power connector
Connect the PS-5V2AEPS power supply to this connector. The power supply provides 5 VDC, 2 A power to the
TC-32.
TC input connectors, measurements, and LED
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.
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TC-32 User's Guide Functional Details
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You can add another 32 differential TC input connections to mini-jack connectors labeled CH0 through CH31
(refer to Figure 2).
The device supports type J, K, S, R, B, E, T, N thermocouples.
Caution! MCC strongly recommends that you ground yourself using a wrist strap before handling the
thermocouple sensors.
Connecting TCs to common-mode voltage sources
You can connect a thermocouple to a common voltage source (AC or DC) as long as the magnitude of the
voltage is within the common mode voltage range specification of 48V (DC) or 3.5V p-p (AC).
Each applied common mode voltage must be less than or equal to the average common mode voltage ±1.4 V.
For example, in Figure 4, there are three TCs connected to three different common mode voltage sources and
two thermocouples that are not connected to anything (floating).
In this example, the average common mode voltage is calculated as follows: (11.4 V+ 10 V + 8.6 V)/3 = 10 V
Each TC channel becomes biased to the average common mode voltage of 10 V.
Each common mode voltage must then be within the 10 V ±1.4 V limits or 8.6 V to 11.4 V.
Figure 4. TC-32 common mode voltage connections example
Cold junction compensation (CJC)
Each TC input on the TC-32 has a high-resolution CJC sensor. When you connect the thermocouple sensor
leads to the sensor input channel, the dissimilar metals at the TC-32 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 CJC technique.
The measured voltage includes both the thermocouple voltage and the cold junction voltage. To compensate for
the additional cold junction voltage, the TC-32 subtracts the cold junction voltage from the thermocouple
voltage.
Increasing the thermocouple length
If you need to increase the length of your thermocouple, use the same type of TC wires to minimize the error
introduced by thermal EMFs.
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TC-32 User's Guide Functional Details
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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 TC-32 is equipped with OTD for all analog input channel. With OTD, any open-circuit condition at the TC
sensor is detected by the software. An open channel is detected by the use of a pull up and pull down resistors
on the thermocouple inputs. An open thermocouple condition forces the input differential voltage outside of the
valid thermocouple voltage range. 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 OTD enabled, 75 nA (max) of input leakage current is injected into the TC. This current can cause an
error voltage to develop across the lead resistance of the TC 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 × 75 nA
To reduce the error, reduce the length of the TC to lower its resistance, or lower the AWG of the wire by using
a wire with a larger diameter. With open-thermocouple detection disabled, 2 nA (max) of input leakage current
is injected into the TC.
Digital I/O
The TC-32 provides up to eight digital inputs and 32 digital outputs that are electrically isolated from the host
computer and from the TC-32 analog circuits.
All DIO bits have internal pull-up resistors to 5 V that can be disconnected with the rear panel slide switches.
The recommended maximum length of the 50-pin cable used to connect the DIGITAL I/O connector to the
digital I/O signal source is 1 foot.
Digital inputs
The TC-32 provides \ digital inputs with rates of 500 port reads or single bit reads per second.
Digital input voltage ranges of 0 V to 15 V are permitted, with thresholds of 0.6 V (low) and 2.2 V (high).
Each digital input has a 100 kΩ pull-up resistor. Use the eight PULL-UP ENABLE – DIN slide switches to
enable or disable the 5 V pull-up option.
Digital outputs/temperature alarms
Each digital output is open-drain, which can of sink up to 100 mA for direct drive applications.
Each digital input has a 100 kΩ pull-up resistor. Use the eight PULL-UP ENABLE – DOUT slide switches to
enable or disable the 5 V pull-up option.
Optionally, you can configure each digital output as an alarm for each TC input. When an alarm is enabled, its
associated output line is driven to the appropriate state determined by the alarm options and input temperature.
You can also use the alarm outputs to control a device or application that indicates when a temperature
threshold has been exceeded.
The alarm configurations are stored in non-volatile memory and loaded at power up.
Alarm settings are applied when changed and at power on. Temperatures are constantly converted on enabled
channels and processed for alarm conditions regardless of the communications connectivity.
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TC-32 User's Guide Functional Details
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Each available alarm mode and setting is explained below.
Alarm input modes
Set independent temperature thresholds T1 and T2
for each alarm.

Trigger alarm when input temperature ≥ T1; reset alarm when
input temperature < T2
Trigger alarm when input temperature ≤ T1; reset alarm when
input temperature > T2

Trigger alarm when input temperature is < T1 or > T2
Alarm error modes 
Alarm on temperature reading only
Alarm on temperature reading, open thermocouple, or common-
mode voltage error
Alarm on open thermocouple or common-mode voltage error only
Alarm output modes 
Alarm disabled; digital output line can be used for normal
operation
Alarm enabled; active low output (output line goes low when
alarm condition is met)
Alarm enabled; active high output (output line goes high when
alarm condition is met)
Alarm output may be latched and will not clear unless explicitly
cleared by the user
The TC-32 provides three alarm indicators –the ALARM LED, the OPEN TC LED on the front panel and,
optionally, the user-configurable digital outputs associated with each channel.
Because the digital alarm outputs are user-configurable, they can be used to supply additional information
(visually, if the digital outputs are used to drive LEDs), such as the channel associated with the alarm condition
or differentiating between threshold and CMV alarms.
Pull-up configuration
By default, pull-up is enabled for all eight digital inputs and all 32 digital outputs. Slide switches on the rear of
the housing can disable pull-up for each digital input bit and digital output bit.
LED indicators
The TC-32 has four LEDs that indicate the power, communication, alarm, and open TC status
POWER LED2
The POWER LED turns on when you plug the power adapter into the TC-32. If a Flash LED command is sent
from an application, the Power LED blinks five times.
ACTIVITY LED2
The ACTIVITY LED turns on when there is a valid connection (USB or Ethernet) and blinks when a command is
sent to the TC-32.
ALARM LED
The ALARM LED turns on when an alarm condition occurs.
OPEN TC LED
The OPEN TC LED turns on when there is an open thermocouple condition.
2Both the POWER and ACTIVITY LEDs blink in firmware upgrade mode. Refer to Updating firmware on page 10.
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TC-32 User's Guide Functional Details
15
EXPANSION connector
Use the EXPANSION connector to connect the TC-32 to a TC-32-EXP expansion device (sold separately) for
applications that need additional analog/thermocouple input and digital I/O channels. A 40-pin expansion cable
is included with the TC-EXP-32.
Refer to www.mccdaq.com for TC-32-EXP product details.
Chassis ground connector
Provides a connection point (#6-32 screw) for chassis ground. Connect this to an external grounding source.
If the TC-32 is connected by USB or by a shielded Ethernet cable to grounded equipment, connecting to an
external grounding source is not needed since the USB/shielded Ethernet connection already grounds the TC-32
and a connected TC-32-EXP.
RESET button
Press and hold this button to restore the TC-32 to its factory default network settings. Refer to Restoring factory
default network settings on page 10
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TC-32 User's Guide Functional Details
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Mechanical drawings
Figure 5. Enclosure dimensions - front
Figure 6. Enclosure dimensions - rear
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TC-32 User's Guide Functional Details
17
Figure 7. Enclosure dimensions – side
Figure 8. Circuit board dimensions
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18
Chapter 4
Specifications
All specifications are subject to change without notice.
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Thermocouple input
Table 1. Generic analog input specifications
Parameter Condition Specification
A/D converter type Delta-Sigma
A/D resolution
24-bit
Number of channels
32
Filtering options
50 Hz or 60 Hz noise filtering, software-
selectable
Isolation
Between any TCx channel and chassis
ground. 500 VDC absolute max
Channel configuration
Software-selectable to match thermocouple
sensor type
Differential input voltage range
±78.125 mV
Absolute maximum input
voltage Between any two TCx inputs
±25 V (power on)
±25 V (power off)
Differential input impedance
50 Hz filtering, power on
26 MΩ
60 Hz filtering, power on
20 MΩ
Input current
Open thermocouple detect disabled
2 nA
Open thermocouple detect enabled
75 nA
Common mode rejection
50 Hz filtering, at DC and fin=50 Hz
110 dB
60 Hz filtering at DC and fin=60 Hz
110 dB
Noise rejection
50 Hz filtering at fin =50 Hz
80 dB typ.
60 Hz filtering at fin =60 Hz
80 dB typ.
Input bandwidth
50 Hz filtering
22 Hz
60 Hz filtering
26 Hz
Crosstalk
Between any two TCx inputs
-90 dB
Sample rate (Note 1)
3 Hz max (per channel)
Common mode voltage range
(Note 2)
TCx channel to TCx channel
±1.40 V
TCx channel relative to chassis
ground, fin = 60 Hz
±3.5 VAC p-p
TCx channel relative to chassis ground
±48 V DC
Input noise
50 Hz or 60 Hz filtering
510 nV rms
Gain error
50 Hz or 60 Hz filtering
0.004 % FSR
Offset error
50 Hz or 60 Hz filtering
3 µV
Measurement sensitivity
(Note 3)
Thermocouple type J,K,T,E,N
0.07 °C
Thermocouple type R,S
0.18 °C
Thermocouple type B
0.60 °C
Warm-up time
20 minutes min
Open thermocouple detect
response time 1 second
CJC sensor accuracy 0 °C to 45 °C
±0.20 °C typ
±0.40 °C max
Note 1: The enabled thermocouple inputs are continuously converted at the maximum A/D converter rate.
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TC-32 User's Guide Specifications
19
Note 2: When thermocouple sensors are connected to different common mode voltages, the channels with
floating thermocouples sensors will be biased to approximately the average value of the applied
common mode voltages. Each of the applied common mode voltages must then be less than or equal to
the average common mode voltage ±1.40 V or [CMVapplied ≤ (CMVaverage ±1.4 V)].
Note 3: Measurement sensitivity is the smallest change in temperature that can be detected.
Channel configuration
Table 2. Channel configuration specification
Sensor Category Condition Specification
Thermocouple
J, K, S, R, B, E, T, N
32 differential channels
Note 4: Channel configuration is stored on EEPROM external to the isolated microcontroller by the firmware
whenever any item is modified. Modification is performed by commands issued from an external
application, and the configuration is made non-volatile through the use of the EEPROM.
Compatible thermocouple sensors
Table 3. Compatible sensor type specifications
Parameter Specification
Thermocouple
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
Accuracy
Thermocouple measurement accuracy
Table 4. Thermocouple accuracy specifications, including CJC measurement error. All specifications are (±).
Sensor
Type
Sensor
Temperature
(°C)
Accuracy Error
Maximum (°C),
15°C to 35°C
Accuracy Error
Typical (°C),
15°C to 35°C
Accuracy Error
Maximum (°C),
0°C to 45°C
Accuracy Error
Typical (°C),
0°C to 45°C
J
–210
1.965
0.910
2.167
0.989
0
0.787
0.361
0.816
0.375
1200
0.752
0.371
1.148
0.508
K
–210
2.295
1.061
2.520
1.152
0
0.821
0.376
0.852
0.392
1372
1.029
0.504
1.560
0.688
S
–50
2.467
1.111
2.655
1.223
250
1.835
0.825
1.961
0.904
1768 0.893 0.361 1.519 0.590
R
–50
2.609
1.174
2.810
1.293
250
1.862
0.837
1.992
0.918
1768
0.754
0.305
1.346
0.520
B
250
2.450
1.090
2.707
1.254
700
0.937
0.424
1.136
0.520
1820
0.610
0.300
1.056
0.467
E
–200
1.754
0.811
1.933
0.880
0
0.775
0.355
0.806
0.369
1000
0.657
0.323
0.989
0.437
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TC-32 User's Guide Specifications
20
Sensor
Type
Sensor
Temperature
(°C)
Accuracy Error
Maximum (°C),
15°C to 35°C
Accuracy Error
Typical (°C),
15°C to 35°C
Accuracy Error
Maximum (°C),
0°C to 45°C
Accuracy Error
Typical (°C),
0°C to 45°C
T
–200
2.005
0.923
2.207
1.005
0
0.836
0.382
0.874
0.400
400
0.544
0.255
0.659
0.297
N
–200
2.255
1.038
2.481
1.134
0 0.908 0.415 0.949 0.437
1300
0.718
0.357
1.157
0.510
Thermocouple measurement accuracy specifications include polynomial linearization, cold-junction
compensation, and system noise. The accuracy specifications assume the device is operated within its enclosure
and with the enclosure in a horizontal, upright orientation. The board should also be warmed up for the
recommended 20 minutes. If the maximum digital output load of 3.2 amps is applied, add an additional 0.30°C
to the typical and maximum accuracy specifications listed above. Errors shown do not include inherent
thermocouple error. Contact your thermocouple supplier for details on the actual thermocouple accuracy error.
Digital input/output
Table 5. Digital input specifications
Parameter Specification
Number of inputs
8 channels
Configuration
Fixed input
Input voltage range
0 V to +15 V
Input type
CMOS (Schmitt trigger)
Input characteristics
100 kΩ pull-up resistor, 28.7 kΩ series resistor
Maximum input voltage range
0 V to +20 V max (power on/off, relative to IGND pins)
Pull-up configuration
All pins pulled up to +5 V via individual 100 kΩ resistors using slide switch SW5.
SW5 default positions are on (pulled up.)
Transfer rate (software paced)
500 port reads per second typ.
Input high voltage
1.3 V min, 2.2 V max
Input low voltage
1.5 V max, 0.6 V min
Schmitt trigger hysteresis
0.4 V min, 1.2 V max
Table 6. Digital output specifications
Parameter Specification
Number of outputs
32 channels, shared with alarms
Configuration
Open drain output
Output characteristics
100 kΩ pull-up, open drain (DMOS transistor)
Pull-up configuration
All pins pulled up to +5 V via individual 100 kΩ resistors using slide switches
SW1-SW4. The default positions for SW1-4 are on (pulled up.)
Transfer rate (software-paced)
Digital output – 500 port writes per second typ.
Output voltage range
0 V to +5 V (internal 100 kΩ pull-up resistors connected to +5 V by default)
0 V to +15 V max (using external pull up resistor)
Off state leakage current
0.1 µA
Sink current capability
100 mA max (continuous) per output pin
DMOS transistor on-resistance
(drain to source)
4 Ω
Note 5: Ground pins labeled IGND are isolated from AGND and chassis ground.
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