DCS side motor current display issue
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There is a motor on site that needs to have its current displayed on the DCS side; how should the range for measuring this motor’s current be set on the DCS side? The current transmitter is available, but the current value at the DCS side is lower than that at the field. How should the current range at the DCS side be calculated? There are formulas that can be used; please, someone knowledgeable, give me an answer! Thank you!
Is it connected to the DCS via 4-20mA? If so, set the range as per normal analog settings; note that the transmitter signal is a 0-20mA signal, which needs to be checked
The input for the normal analog range is incorrect
You first need to figure out what the range of output from your current transducer is. And since there are now actual measurement values available, it’s also possible to calculate it backwards
Regardless of the range of your current transducer, the AI cards in a DCS typically accept analog signals in the 4–20mA range; the corresponding range will therefore be determined by the actual current range of your frequency converter. If the transmitter does not output a standard 4–20mA signal. Then get a transmitter that outputs a standard current signal. Typically, inverters provide a 4–20 output.
If the transmitter and the current transformer are integrated, the setting can be done according to the transmitter’s range. If they are separate, first determine the transformation ratio of the current transformer, then find out the range of the current transmitter, and finally calculate the 4–20 mA range corresponding to the DCS system. The formula is very simple: transformation ratio * transmitter input range = DCS range.
Is it the value after the transformation ratio multiplied by the transmitter’s range?
Current transformer ratio/0–5A/4–20mA/dcs range
The range can be determined based on the 4-20mA analog signal, but I usually use network communication to display the motor current
The normal range for motor current is set based on the range of the current transformer in the distribution cabinet or that of the motor protector