What is the role of the thermocouple holder in DCS?
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This post was last edited by Wandering Dawn on 2016-7-3 08:44. Dear seniors and colleagues: What is the function of the DCS thermocouple card (control unit)? Cold-end compensation? Also, how can the cabinet room be kept at a constant temperature?
The function of the thermocouple card (which is equivalent to temperature sensing) is to convert the mV signal into a standard current signal for input to the DCS; cold-junction compensation is also carried out here...
The thermocouple card converts the MV signal generated by the thermocouple into a signal that can be recognized by a computer for internal processing; its function is equivalent to that of a temperature transmitter + 4-20mA input card
This is pretty much the same as Honeywell’s card modules; they are similar in most aspects
I understand signal conversion; what I actually want to know is whether it can serve as a cold-end compensation
For thermocouple measurements, cold-junction compensation is necessary. At the terminal block, there is a thermistor, and the thermocouple module detects this thermistor signal to perform cold-junction compensation.
What is the difference between using a safety barrier + AI (TC) to connect to the DCS, and using transmitters + safety barriers plus AI cards to connect to the DCS? Is their budget that large? Please ask an expert to answer