The Siemens 3RB1246-1PG20 is an overload relay for full motor protection, covering the 1.25 to 6.3 A adjustment range. It fits the S00 and S0 contactor frame sizes and supports stand-alone installation with a straight-through main circuit. The auxiliary circuit uses screw-type terminals. The relay offers trip classes 5 through 30, giving the panel builder flexibility to match the motor's thermal time constant — Class 10 for standard start, Class 20 for heavy starts, Class 30 for very high-inertia loads. The manual-automatic-remote-reset selector covers the common control schemes without an add-on module. Integrated ground fault detection is a notable feature for this class: it monitors for leakage to earth and provides a monostable output for ground fault signaling at AC 110-120 V, 50/60 Hz. This saves a separate ground-fault relay in panels where earth-leakage protection is required alongside overload protection.
This part is at current lifecycle stage. Sourcing is through the franchise channel with factory traceability and warranty coverage.
Integration Notes
The S00/S0 footprint is the standard Siemens compact overload relay form factor, designed to mount directly to the matching contactor or as a stand-alone unit on DIN rail. The straight-through main circuit keeps wiring simple — line in, load out — without looping the power conductors through the relay body. The ground fault signaling output is monostable and rated for AC 110-120 V, 50/60 Hz. In a typical panel, this output can drive a pilot light or PLC input directly, but verify the sink current of the connected load stays within the relay's rated switching capacity.