Current access to DCS system
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What materials are needed to introduce the current from the motor or pump into the DCS system? Thanks! ~~~
Add a current transformer to the power line of the motor electrical control cabinet, and then you may need to add a current transmitter to send it to the DCS. If communication is used, you only need to add current parameters to the communication equipment of the electrical control cabinet, without adding hardware.
In terms of electrical aspects, a current transducer is added with an output of 4~20MA. Directly into the card. Pay attention to the power distribution dialing of the card, which is usually unplugged. It is best to keep it separate from the card that distributes power to the transmitter.
Add a current transformer + current transmitter, pay attention to the current matching problem when selecting the transmitter
If you have a frequency converter, connect it directly to the 4-20mA output terminal of the frequency converter. If you don’t have a frequency converter, you need to add a current transformer and a current transmitter (the one with a transmission output of 4-20mA)
It is best to use a signal isolator before connecting to the DCS to avoid introducing interference signals and affecting other channels.
You are referring to the control circuit of the motor (220VAC). The DCS module is generally 24VDC, so an intermediate relay is generally added, which is equivalent to providing a passive contact!
The electrically added current transducer outputs 4--20mA to DCS AI (configured as a four-wire system, that is, it does not feed 24V DC). And configure the measuring range to be consistent with the measuring range of the electrical current transmitter.
A current transformer is needed to convert the current signal into a 4-20mA DC standard signal. It enters the DCS card through the cable and must be isolated.