Replacement coil for SIRIUS size S0 contactors
The Siemens 3RT6926-5AG21 is a SIRIUS-branded replacement magnet coil designed for size S0 motor contactors rated up to 18.5 kW. It accepts a 110 V AC control supply at both 50 Hz and 60 Hz, with the coil's voltage tolerance spanning 0.8 to 1.1 times the rated value at 50 Hz and 0.85 to 1.1 at 60 Hz. Connection is via screw terminals, matching the standard wiring practice for S0 frames.
The 110 V AC coil voltage is the nominal pick-up and hold value; the tolerance band (0.8 to 1.1 at 50 Hz, 0.85 to 1.1 at 60 Hz) tells you the coil will reliably operate when the control supply stays within 88–121 V AC at 50 Hz or 93.5–121 V AC at 60 Hz. A supply dipping below the lower threshold risks the contactor dropping out mid-cycle.
This coil mounts directly onto the magnet stack of a SIRIUS size S0 contactor frame. The screw-terminal connection accepts standard solid or stranded wire; no special tooling is needed beyond a screwdriver. The coil's footprint matches the existing S0 contactor housing, so a panel wired for a 3RT1016-2GG22 or similar S0 contactor can accept this coil without rewiring the control circuit — provided the control voltage is 110 V AC.