na2121The relay type NA21 is typically used in HV, MV and LV radial networks as feeder or power transformer protection. In solidly grounded systems the residualNA21 Datasheet. Part #: AHNA21. Datasheet: 136Kb6P. Manufacturer: Panasonic Semiconductor. Description: Relay for control panel of 1c 10A, 2c 5A and 1a