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GE 12CHC12A2A
Product Name: GE 12CHC12A2A Fault Detector Relay — Three-Phase High-Speed Nondirectional Overcurrent Relay
Overview: The 12CHC12A2A is a Type CHC fault detector relay from GE. It is a three-phase, high-speed, nondirectional overcurrent relay consisting of an induction cup unit (PFD), a target unit, and a telephone-type seal-in unit, all mounted in an S-2 size drawout case. It is designed to act as a current fault detector in conjunction with distance relays, preventing mis-operation of timers or false breaker tripping due to loss of relay potential supply.
Detailed content
Technical Specifications:
- Type: CHC (Three-Phase High-Speed Nondirectional Overcurrent Relay)
- Catalog Number: 12CHC12A2A
- Rated Current: 5 A
- Frequency: 60 Hz
- Pickup Range (Phase-to-Phase): 2 – 8 A
- Target Coil: 1 A
- Case Size: S-2 size drawout case
- Construction: Induction cup unit + target unit + seal-in unit
- Interchangeability: Mechanically and electrically interchangeable with PJC31C or D
Features: High-speed operation for rapid fault detection; seal-in unit allows the relay to remain picked-up even when load current exceeds minimum fault current, preventing false re-tripping at reclosure; target unit gives visual fault indication; drawout case design for easy maintenance and replacement.
Applications: Used as a current fault detector together with distance relays in protection schemes; protects associated timers against burnout due to loss of potential supply; prevents false circuit breaker re-tripping at the instant of reclosure; applied in (1) short or open circuits involving the potential supply, (2) switching transients, and (3) line-side potential supply configurations.
Installation & Usage Notes: Each CHC relay is cleaned, tested with report, and carries a one-year warranty from the supplier; pickup and target coil ratings are per GEI-74676 instruction; install in compatible S-2 size drawout cases; verify the 2–8 A phase-to-phase pickup adjustment matches the application.
