Contact configuration and switching
The 3RH1140-1JB40: Four NO contacts, zero NC, no leading or lagging auxiliary, no make-before-break. That's a clean 4-pole normally-open set — you're getting four independent form-A contacts that all close when the coil picks up. The surge suppressor is built in with a diode across the coil, so external flyback protection isn't needed for DC switching. Rated switching capacity drops with voltage: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, 2 A at 500 V, 1 A at 690 V. For DC control circuits, the 24 V / 10 A line is the one that matters for most panel auxiliaries. The 6 kV surge voltage resistance and pollution degree 3 rating mean it's built for industrial environments with conductive contamination.
Termination and wiring
Screw terminals accept solid or ferruled stranded: 2x (0.5...1.5 mm²), 2x (0.75...2.5 mm²), or 2x 4 mm² per clamp. AWG equivalent is 2x (20...16), 2x (18...14), or 1x 12. That's enough capacity for daisy-chaining through the auxiliary contacts without piggyback terminals. Strip length around 8-10 mm is typical for this class of screw clamp.
Environmental and mechanical limits
Operating temperature range -25 to +60 °C, storage and transport -55 to +80 °C. Shock resistance is 10g at 5 ms and 5g at 10 ms. Mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward — flexible for tight enclosures. Mechanical life is 30 million operations typical, which is standard for a SIRIUS auxiliary relay.