Phase sequence relay protection works
Sampling three-phase power supply and processing, in the power phase sequence and the protection device input phase sequence phase of the case, the output relay connected to the main control circuit connected to the device. There are two types of products are: when the power phase sequence changes, phase sequence does not match, the output relay can not be connected, thus protecting the equipment, to avoid accidents; the other use of digital micro-core technology products can be automated Phase sequence recognition, and to achieve automatic phase sequence conversion, to ensure that the motor constant phase sequence rotation.
Three-phase power supply in turn access the protector U, V, W (some R, S, T or L1, L2, L3) three wiring points, phase sequence protection of the auxiliary contacts generally have a normally open normally closed. Access control circuit, the specific normally open or normally closed according to the control principle or wiring diagram to pick, when the phase sequence error or lack of time when the auxiliary protection of the protector action normally open normally closed, normally closed normally open The If it plays a protective role, it should be closed contact.