Dold RK9872.11/100 3/NAC400/230V 50/60HZ Safety relay, Part N: 0067872

The space saving phase monitor RK 9872 from the Varimeter family monitors under- and overvoltage as well as phase sequence in 3-phase systems. The response values are fixed. When connecting the measuring voltage to the inputs L1-L2-L3 and fault free system the relay switches on. When the measuring voltage is connected the unit checks a clockwise phase sequence. If this is not the case the yellow LED flashes. The output relay will not energise. After detection of under- or overvoltage on one or more phases for more the 5 sec. the relay switches off. The relay stays off for at least 2 seconds. The phase monitor measures the arithmetic mean value of the 3 phases against neutral.