S2 contactor for 690 V AC-3 motor switching — active line, screw terminals
The Siemens 3RT7036-1AV00 is a size S2 contactor from the SIRIUS family, rated for AC-3 switching up to 690 V maximum — that covers 400 V and 480 V motor loads with headroom for 690 V IEC networks. Three main NO contacts handle the power circuit; screw-type terminals on both main and auxiliary circuits accept 2x (0.5…1.5 mm²) solid or 2x (0.75…2.5 mm²) stranded copper. The DC coil holds at 0.36 W and pulls in at 0.79 W, which keeps the control transformer small in a multi-contactor panel. IP20 on the front face protects against finger contact; the terminal area is IP00, so live parts are exposed — standard for panel-mount contactors where the enclosure provides the outer barrier. Mounting is screw-fixed or snap-on onto 35 mm DIN rail per DIN EN 50022, and side-by-side mounting is allowed with no derating gap. The mounting position permits ±180° rotation on a vertical surface and ±22.5° tilt forward/backward — useful when the panel layout forces an angled rail. Pollution degree 3 means it's rated for industrial environments with conductive contamination, so no conformal coating is required for most factory-floor installs.
Coordination and selectivity — fuse sizing for Type 1 and Type 2
For Type 2 coordination (no damage to the contactor under short circuit), the required backup fuse is a gL/gG NH 3NA 80 A. For Type 1 coordination (contactor may need replacement after fault, but no fire or arc-flash hazard), the fuse rating goes up to 160 A. This matters when the panel designer is coordinating with upstream MCCB or fuse-switch ratings — the 80 A Type 2 limit is the tighter constraint for selectivity studies. Surge voltage resistance is 6 kV, which aligns with IEC 60947-1 overvoltage category III for fixed-installation contactors.
Auxiliary contact compatibility and PLC-level switching
The contactor accepts a product extension auxiliary switch block, which is useful when adding early-make or late-break contacts for feedback to a PLC. The auxiliary contacts are rated for PLC control reliability at 17 V, 5 mA — meaning they can switch solid-state inputs without gold-plating or wetting current issues. DC-13 switching at 220 V is rated at 0.3 A, covering small DC solenoids and indicator lamps in the control circuit.
Environmental and mechanical limits
Operating temperature range is -10 to +55 °C; storage range is -25 to +70 °C. Shock resistance is 15g at 5 ms and 8g at 10 ms sine pulse — adequate for most industrial panels but not for direct mounting on high-vibration machinery (a separate shock mount may be needed). Maximum mechanical switching rate is 800 operations per hour at AC-3 duty, dropping to 250 per hour at AC-4 (plugging/inching).