Answer / carl_ellis

1) Most likely, the 4-20mA scaling (what the 4-20mA represents) is not the same on the transmitter as it is on the DCS.

The scaling has to match, that is, be the same on both the transmitter and the DCS analog input.

2) A ground loop will cause an offset. The offset can be negative or positive, depending on the polarity of the ground loop.

Eliminating ground loops can be a major task, so most times, a loop isolator is used to isolate the transmitter from the DCS, which eliminates the ground loop.

Carl Ellis
Measure First

Answer / shahid

Carl Ellis is give the good answer that is the technical error that may occur but some time there is possibility of miss matching in the range of DCS & the field transmitter.That's why should check the both ranges of URV-LRV.

Answer / maheshrp

Reason of DCS and field equipment range different so dcs and field variable reading
So dcs & field range same as problem your solve

Answer / raghubir nishad

Range Can match in Field instrument or PLC/DCS both side.

what step is taken for ESD ( emergency shut down) in DCS REPLY to hashimka20009@gmail.com

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