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USER GUIDE
SCC-TC Series Thermocouple
Input Modules
The SCC-TC Series thermocouple input modules, SCC-TC01 and
SCC-TC02, accept input signals from B-, E-, J-, K-, N-, R-, S-, and T-type
thermocouples. Each module contains thermistor circuitry powered by
2.5 V, to compensate for cold-junction effects and can detect open
thermocouple circuits. Each module has one thermocouple input channel,
which consists of a gain of 100 differential amplifier and a dual-pole 2 Hz
filter.
Note Alternativel
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bold Bold text denotes items that you must select in the software, such as menu items and dialog box options. Bold text also denotes parameter names. italic Italic text denotes variables, emphasis, a cross-reference, or an introduction to a key concept. Italic text also denotes text that is a placeholder for a word or value that you must supply. monospace Text in this font denotes text or characters that you should enter from the keyboard, sections of code, programming examples, and syntax e
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❑ Documentation – One of the following: � SC-2345/2350 User Manual � SCC-68 User Guide – SCC-TC Series Thermocouple Input Modules User Guide – Read Me First: Safety and Radio-Frequency Interference – SCC Quick Start Guide ❑ Tools – 1/8 in. flathead screwdriver – Numbers 1 and 2 Phillips screwdrivers – Wire insulation strippers You can download needed documents from ni.com/manuals. Note Software scaling of measurements is not supported on the Macintosh operating system. Refer to the Scaling Volt
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the inputs of the second-stage SCC. An example of dual-stage conditioning in an SCC-TC0X followed by an SCC-LP01 lowpass filter module. Sockets J9 to J16 also are available for digital input/output (DIO) conditioning or control. Refer to the SC-2345/2350 User Manual for more information on configuring, connecting, and installing SCC modules Note SCC-TC0X dual-stage configuration is only available in NI-DAQmx 7.1 or later. Connecting the Input Signals Note The signal names have changed. Refer
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E/M Series SCC-TC0X DAQ Device Ref 5 V 10 MΩ Thermocouple Source 10 kΩ + 2-Pole Filter/ TC+ AI (X ) 10 kΩ – Buffer Stage TC- Offset 10 MΩ Calibrator GND (SCC-TC02 only) Ref 5 V AI SENSE 4.75 kΩ AI GND 1% 5 kΩ LM 4040 0.1% 2.5 V + 0.1 μF AI (X+8) 0.1% – + o 5 kΩ 10 μF -t 0.1 μF o at 25 C 16 V 2.5 kΩ Figure 1. SCC-TC0X Signal Connections For more information about how to configure the SCC-TC0X module using NI-DAQmx, refer to the SCC Quick Start Guide. Using the TC0X Scaling Voltage Measu
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temperature measurements. To make this conversion, complete the following steps: 1. Measure the thermocouple voltage. a. Read the thermocouple channel on the E/M Series DAQ device V [CH(X)]. ESERIES b. Calculate the thermocouple voltage by using the following formula: V ESERIES V = -- --- ---- ---- ---- --- - TC 100 where V is thermocouple voltage. TC V is E/M Series DAQ device voltage. ESERIES This step provides proper scaling for the thermocouple amplifier in the SCC-TC0X. 2. Measure the r
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Detecting Open Thermocouples The SCC-TC0X contains a 10 MΩ pull-up resistor that connects to +5 V to detect open thermocouples. To determine if you have an open thermocouple, check whether the corresponding E/M Series DAQ device channel is saturated. The pull-up and bias resistors saturate the channel by applying +2.5 V at the input of an open channel. This results in saturation to either the positive or negative rails of the EM Series DAQ device (±10 V). Errors Due to Open-Thermocouple De
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Cold-Junction Sensor The cold-junction sensor voltage output varies from 1.91 to 0.58 V over a 0 to 55 °C temperature range. Note NI-DAQmx includes thermistor conversion utilities that implement the equations listed below. Refer to your software documentation for more information on these utilities. You can use the following formulas to convert the cold-junction sensor voltage to cold-junction temperature: T() °C = T – 273.15 K where T is the temperature in degrees kelvin. K 1 T = -- ---- ---
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Calibrating System Offsets To calibrate the offset voltage of the SCC-TC0X in the system using the E/M Series DAQ device, complete the following steps. The E/M Series DAQ device must be powered for 30 minutes before you calibrate the offset voltage. 1. Select the desired channel and gain on the E/M Series DAQ device. 2. Short the inputs on the SCC-TC0X screw terminals or miniplug. 3. While acquiring data on the selected channel, use a screwdriver to adjust the potentiometer protruding throug
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Specifications These specifications are typical at 25 °C unless otherwise stated. Analog Input Number of input channels.......................1 DIFF Input signals............................................Thermocouples of types B, E, J, K, N, R, S, and T Input signal range ...................................±100 mV Input impedance .....................................10 MΩ powered on, 10 kΩ powered off or overload Bandwidth...............................................2 Hz Amplifier Character
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1 Measurement Accuracy Thermocouple Temperature Maximum Typical Type Range (°C) Inaccuracy (±°C) Inaccuracy (±°C) B 400 to 600 2.5 0.31 600 to 1,800 2 0.13 E –200 to –100 2 1.76 –100 to 600 1 1 600 to 1,000 1.5 0.6 J –200 to –100 2 1.6 –100 to 500 1 0.9 500 to 1,100 1.5 0.72 K –200 to –100 2.5 1.25 –100 to 600 1.25 0.67 600 to 1,200 2 0.45 N –200 to –100 2.5 2 –100 to 1,300 2 0.7 R –50 to 0 3 1.24 0 to 100 2 0.82 100 to1,600 1.75 0.4 S –50 to 0 3 1.3 0 to 1,400 2 1 1,400 to 1,600 2.5 1 T –200 t
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Cold-Junction Sensor Cold-junction sensor accuracy................±0.4 °C max from 15 to 35 °C, ±0.75 °C max from 0 to 15 °C and 35 to 55 °C Output .....................................................1.91 V (0 °C) to 0.58 V (55 °C) Note The accuracy specification includes the combined effects of the temperature sensor accuracy and the temperature difference between the temperature sensor and any thermocouple connector. The temperature sensor accuracy includes component tolerances, temperatu
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1.87 cm (0.74 in.) 7.93 cm (3.12 in.) 3.55 cm (1.4 in.) Figure 3. SCC-TC02 Dimensions Weight TC-01 .............................................. 25 g (0.9 oz) TC-02 .............................................. 22 g (0.8 oz) Screw terminal wire gauge..................... 24 to 12 AWG I/O .......................................................... One 20-pin right angle male connector, 3-pin screw terminal system (SCC-TC02); two-prong mini-connector (SCC-TC01) Screw terminal field-wiri
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Environmental Operating temperature ............................0 to 50 °C Storage temperature................................–20 to 70 °C Humidity.................................................10 to 90% RH, noncondensing Maximum altitude...................................2,000 m Pollution Degree (indoor use only) ........2 Safety This product is designed to meet the requirements of the following standards of safety for electrical equipment for measurement, control, and laboratory use: � IEC
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CE Compliance This product meets the essential requirements of applicable European Directives, as amended for CE marking, as follows: � 73/23/EEC; Low-Voltage Directive (safety) � 89/336/EEC; Electromagnetic Compatibility Directive (EMC) Note Refer to the Declaration of Conformity (DoC) for this product for any additional regulatory compliance information. To obtain the DoC for this product, visit ni.com/ certification, search by model number or product line, and click the appropriate link in
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Table 1 lists the signal connection corresponding to each pin. AI (X) and AI (X+8) are the analog input signal channels of the E/M Series DAQ device. AI GND is the analog input ground signal and is the reference for AI (X) and AI (X+8). A GND is the reference for the ±15 V supplies and REF 5V. AI GND and A GND connect to the SC-2345/2350 at the SCC-PWR connector. Table 1. SCC Module Pin Signal Connections for SCC-TC0X Modules Pin Number Signal 1 AI (X) 2 — 3 — 4 AI (X+8) 5 — 6 DAQ Device A
