Motor protection

Reyrolle 7SR17
The Reyrolle 7SR17 Rho is a numeric protection relay with four current inputs and optionally three voltage inputs. The relay is applied to motors and their connections providing an integrated protection system.
Features
The relay is typically used as a stand-alone device but can be supplied with an external unit to interface with remote temperature detectors embedded in the motor or installed on auxiliary equipment.
The Reyrolle 7SR17 Rho relay includes thermal protection optimised for motor applications and motor starting supervision algorithms. Several other protections are also provided and are selectable as required so that a solution appropriate to the installation can be achieved.
The Reyrolle 7SR17 Rho is housed in an E4 case.
Full user configurability and integrate logic allows the optimal configuration of relay input and output functionality.
Optional RTD inputs
Cold load settings
Eight settings groups
Password protection
Self-monitoring
Circuit breaker trip counter
Fault, event and waveform records
Functions
Protection functions
Stall protection (14)
Under/over voltage (27/59)
Power/power factor (32/55)
Undercurrent (37)
Current unbalance protection (46)
Phase reversal (46Ph Rev)
Voltage unbalance (47)
Start protection (48/66)
Motor thermal overload (49R)
Directional overcurrent (67)
Directional earth fault (67G/67N)
Backspin protection (81B)
Under/over frequency (81)
High impedance REF (87REF)
Temperature inputs (via comms port) (RTD)
Supervision functions
Circuit breaker fail (50BF)
CT supervision (60CTS)
VT supervision (60VTS)
Trip circuit supervision (74T/CCS)
Monitoring functions
Instrumentation