Datakom DPR-350 Series, Руководство пользователя

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DPR-350 User Manual Ver_01 Firmware V-1.0
Cold load pickup operation is used to prevent unwanted conditions while energizing after long duration
power losses. Temporary pulse currents which exceed protection threshold values may be formed when
restoring power, depending on the characteristics of the network’s load. These current transients may be
due to the following reasons:
- Pulse magnetization currents of transformers
- Starting currents of asynchronous motors
- Collective activation of air conditioning of heating loads
Protections should normally be configured so as not to trip the breaker in similar transient situations.
However, configuring the protection functions to consider such transient current fluctuations will not
always be possible as it will require setting very high values or very long timers. Instead, cold load pickup
will temporarily inhibit protection threshold values to prevent faulty breaker trips.
10.8. COLD LOAD PICKUP (CLPU 50/51)