my temperature transmitter in field showing 700 degree , whereas in dcs showing 459 degree, how to resolve this?
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Answer Posted / 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
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