Synchro-check (Paralleling)
The synchro-check (paralleling) protector trip relay compares the voltage, frequency and phase angle of two supplies and operates a relay according to the state of synchronization of the supplies. If the two supplies are not synchronized, the relay operates to provide a control output. The relay output can be used for alarm or control purposes. The unit also provides a dead bus function. If the bus supply fails, the relay operates and the output can be used to switch in an emergency generator.
Basic Parameters
- Available with three Voltage ranges
- Adjustable nominal Voltage range
- Adjustable synch tolerance
- Dead bus function on/off switch
- Power on LED (green)
Operation
As part of a manual control system, the operator will make adjustments to generator voltage (excitation) and frequency (engine speed) using a synchroscope or lamps and will then attempt to manually close the breaker. This synchro check protector will qualify that two systems are closely matched before permitting the breaker to close.
As part of an automatic synchronizing arrangement, the synchro-check (paralleling) trip relay can be used as an independent backup or checking device to ensure the two systems are suitably matched before the breaker can close. The synchro-check (paralleling) trip relay continuously monitors the voltage, phase displacement and frequency of the two supplies. While the two supplies match in volts, frequency and phase to the degree set by the %Volts control, the sync LED illuminates and the relay is energized, indicating that the two supplies are matched and it is safe to close the breaker. The relay is fitted with a selectable Dead Bus detection function. If there is a requirement for a continuous supply or emergency power, then the generator can be connected without synchronizing, thus ensuring continuity of supply. The absence of the bus voltage will cause the relay to energize.
Specifications
| Brand | Crompton |
| Model | PLL/D |
| Input Frequency | 50Hz, 60Hz |
| Input Range | 1P3W 100-139V L-N 0-6AAC, 3P4W 173-240V L-N 0-6AAC |
| ECCN | EAR99 |
| Tariff Code | 8536.49.0099 |