PAS-380/480
Model PAS 3P4W 220/277VAC L-N (380/480V L-L) 0-6AAC Relay Reverse Power, 50/60Hz, Protector Trip Relay, Crompton
REVERSE POWER (CURRENT)
The Reverse Power protector trip relay monitors a single- or three-phase supply for reverse power and trips a relay if it detects reverse power (I x cos Φ) over a set limit. The relay output is typically used to prevent ‘motoring’ of a generator (where the generator turns the engine), which can damage the engine.
Basic Parameters
- Available with three voltage ranges 100-120V, 173-240V and 380-480V (Un)
- Adjustable nominal current range, 2, 3, 4, 5, 8 & 10 Amps (In)
- Adjustable trip delay 0.5-20s
- Adjustable set point 2-20%
- Power on LED (green)
Operation
The Reverse Power trip relay provides continuous surveillance of AC generators against motoring. Reverse power relays are used to detect the failure of the prime mover (engine) when active energy (Watts) flows into the generator causing rotation - the set will operate like an electric motor which can cause significant mechanical damage. This relay offers an adjustable reverse power set between 2% and 20% of the nominal power and time delay adjustment range of 0 to 20 seconds. The protector relay estimates the power level in the system by measuring current and power factor, but does not actually measure the system voltage. When the reverse power level exceeds the set point, and after the time delay has elapsed, the relay will energize and the red LED will illuminate to indicate the trip condition. The relay will automatically reset once the power level falls below the set point minus the fixed differential of 1% causing the LED to extinguish and the relay to de-energize. Note: The % set potentiometer trimmer on the front label is calibrated as a percentage of the current rating e.g. of 5A and not of the forward kW.
Characteristics
Specifications
Brand | Crompton |
Model | PAS |
Input Range | 1P2W 220-277V L-N 0-6AAC, 3P4W 220-277V L-N 0-6AAC |
Input Frequency | 50Hz, 60Hz |
Tariff Code | 8536.49.0099 |
ECCN | EAR99 |