Over-current protection relay SPR10

thermalACfor transformers

The numerical relays SPR10, powered by the current transformers (CTs), do not require an external power supply voltage. They are the ideal choice for installation in remote locations where auxiliary supply is not available. Two input circuits of residual current are available in order to insert or exclude the residual current from the power supply circuit. When the protected circuit is de-energized the operating status (rest / trip) is signaled by means of a mechanical indicator fl ag. STANDARD PROTECTIVE & CONTROL ELEMENTS • Phase overcurrent side H and side L • Maximum Residual Overcurrent • Negative sequence overcurrent transformer SW PACK OPTIONAL CONFIGURATION • Thermal Image Transformer The numerical relay powered by the current transformers (CTs) does not require an external power supply voltage. They are the ideal choice for installation in remote locations where auxiliary supplies are not available.The relays derive energy for operation from standard 1 A or 5 A current transformers.The SPR10 relay can be used in radial networks as feeder or power transformer protection.In solidly grounded systems the residual overcurrent protection can be used on feeders of any length, while inungrounded or Petersen coil and/or resistance grounded systems, the residual overcurrent protection can beused on feeders of small length in order to avoid unwanted trips due to the capacitive current contribution of thefeeder on external ground fault.