A contactor with the specification 220V AC 50Hz, 4NO + 4NC is an electromechanical switch used to control high-power electrical circuits. Here's what each part of the specification means:
1. 220V AC 50Hz:
The coil of the contactor operates on 220 volts AC at a frequency of 50 Hz. This is the standard voltage and frequency for many electrical systems.
2. 4NO (4 Normally Open contacts):
This means the contactor has four normally open (NO) contacts. In their default state (when the contactor is not energized), these contacts are open, meaning no current flows through them. When the contactor is energized, these contacts close, allowing current to flow.
3. 4NC (4 Normally Closed contacts):