What it is and key fit decisions
The Siemens 3RT1364-6AF36 is a SIRIUS contactor in the S10 frame size, with an AC coil rated for 48 to 130 V at 50/60 Hz. The contactor is screw-fixed to the mounting surface, not snap-on DIN rail, so panel integration means drilling or tapping the backplate — account for that in the BOM if you're swapping from a DIN-rail style. Coil pick-up is guaranteed at 80% of rated voltage, and drop-out occurs at 110% of rated voltage — meaning this contactor holds in cleanly down to about 38.4 V on a 48 V nominal coil, and drops out if the control supply swells above about 143 V. That's a wide operating band, useful on lines with saggy or lightly regulated control transformers. Coil draw is 4 VA at both 50 and 60 Hz, which is modest for the S10 frame.
Dimensions are 196 mm high, 140 mm wide, 153 mm deep. That depth is the body only — add for wiring space and finger clearance. The contactor can be mounted on a vertical surface, rotated ±180°, or tilted forward/backward up to 30° at 0° rotation. If you're packing this into a shallow enclosure, that forward clearance is the tightest constraint.
Wiring and auxiliary contacts
That's typical for control wiring up to 14 AWG. The two instantaneous N/O contacts are rated at 24 V / 3 A, 48 V / 1.5 A, 110-125 V / 0.55 A, 220 V / 0.3 A, 230 V / 4 A, 400 V / 3 A, 500 V / 2 A, and 690 V / 2 A. Note the 230 V and 400 V ratings are higher than the low-voltage ones — that's the AC-15 / utilization category curve at work; don't assume linear derating. Up to two additional auxiliary contact blocks can be attached to this contactor, giving flexibility to add more N/O or N/C contacts without a separate relay.