How to split the TC/RTD reading to two reading devices


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I like share signal from Thermocouple/RTD to digital temperature controller and also to data logger. How should I do? Is there any accuracy impact if I share the signal like that?
1) The cost of doing business typically involves using dual element T/C's or RTD's, with one element wired to each device.

2) Running an RTD in parallel to another device cannot be done, the result will be total garbage.

3) A thermocouple signal can be run in parallel to a 2nd device using thermocouple wire (not copper wire). The process industries that use temperature transmitters deny this and do not believe it, but the heat treat industry did it for years. There can be issues with common mode and/or thermocouple break circuits interfering with one another, but there are cases where it can work.

4) Some devices have a 're-transmit' capability, typically a 4-20mA or 0/1-5Vdc output that tracks the input, but yours clearly doesn't or you wouldn't be asking. But next time around, think ahead . . .
Yes , I agree. I have seen the transducer which convert RTD values to mA and same is applicable to TC. It can be used for your purpose.
Go for ABB make temperature transmitters. They are universal input type temperature transmitters. so, you don't have to worry about the type of input. The transmitter gives out 4 - 20mA analog signal / HART signal / FF signal whichever is needed for you. Please select the type of output you need.

The type of output which you should select depends on the controller / recorder - what they can accept as input reference?

Trust my answer is bit tough to understand yet it makes some sense.