hi,

Anyone can explain that what is happening in the transmitter if we are connecting HART communicator in the loop and feeding 25% or any values

 

If you connect a HART communicator to a HART transmitter in a point-to-point current loop, the transmitter does what is always does

- it converts the primary variable to a 4-20mA value on the current loop.

- it responds to request(s) from the HART master, the HART communicator, for HART information, assuming the HART communicator uses the address zero for point-to-point communications

The HART data (variables, diagnostics) is constantly updated inside the transmitter but is only put on the current loop in response to the HART master's request.

I'm not sure what type of HART transmitter accepts a written value from a HART master, but many HART devices have the capability to go to a fixed output value in response to a particular command (constant current output, constant current source mode, Loop Test).