Magnelab’s MCT-0016 is a 16-mm 4-20 mA Output CT that transforms an AC current to a 4-20 mA signal. It is available in 10A, 20A, 50A and 100A input ratings.
This 4-20 mA Output CT is powered from the 4-20 mA DC loop circuit. In most cases a loop voltage of 20 VDC is sufficient to power the device. However, if you are using a shunt in the current loop to generate a detectable voltage (e.g. 250 Ohm), you must take the voltage drop across the shunt into account. Of course you may also provide additional voltage to the 4-20 mA DC loop if necessary.
The MCT-0016 is +/- 2% accurate at full scale. It has a response time of 100 ms.
4-20 mA CTs are popular because they differentiate a fault condition from zero detection. With the MCT-0016, when there is no current on the primary, the measuring device will still see a 4 mA signal. Similarly, at the rated current, the measuring device will see 20 mA. However, when the loop circuit is broken for any reason, as you’d expect, the measuring device will see 0 mA, and the unit detects an error condition.
Because of this special ability to detect error conditions, 4-20 mA Output CTs are often used in control applications (you wouldn’t want to something to be controlled erroneously if the circuit was broken!).
You can view all of our current sensors here.