In the UVR(Under Voltage Relay) there is a knob for the
hysteresis setting. what is this setting? its threshold is
given from 5% to 50%. please help me....
Answer Posted / kj
The hystersis is the difference between the voltage at
which the relay operates at and resets at.
For example the UVR is set to open the contacts at 200
volts and it can be set to close at 211.5 volts (for 230
volt sensing). This would be 5% hystersis setting.
This is to stop the relay switching on and off continuously
when the voltage is around 200 volts.
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