The 7SR242 is used as a protection, control and monitoring relay for two winding transformers of all vector groups, primary configurations/connections and earthing connections.
The relay functionality also allows its application in auto-transformer and reactor protection schemes.
Relays are housed in size E8 or E10 cases. Integrated logic is provided to allow the optimal configuration of relay functionality with the relays analogue inputs and binary input/output circuits.
Protection, control, instrumentation and metering functionality is accessible via data comms channel(s). A front USB port for local PC connection or rear electrical RS485 port for remote connection is provided. Additional rear port options are available.
Cold load settings
Eight settings groups
Password protection - 2 levels
User programmable logic
Circuit breaker trip counters
Fault, event and waveform records
Negative phase sequence overcurrent (46NPS)
Thermal overload (49)
Overcurrent (50, 51)
Earth fault (50G, 50N, 51G, 51N)
Neutral voltage displacement (59N)
High impedance REF (64H)
Biased differential (87BD)
High-set differential (87HS)
Circuit breaker Fail (50BF)
Trip circuit supervision (74TC)
Inrush detector (81HBL2)
Over-fluxing detector (81HBL5)
Primary/secondary currents phases and earth direction
Relay operate and restraint currents
Positive phase sequence (PPS) current
Negative phase sequence (NPS) current
Zero phase sequence (ZPS) current
Primary/secondary single phase voltage
Frequency and fluxing
Historical demand record