Panel Fit and Mounting
The 3RT2045-1AP00-1AA0 is a Size S3 power contactor from the SIRIUS family, designed for screw and snap-on mounting onto a 35 mm standard mounting rail per DIN EN 60715. Its dimensions — 70 mm width, 140 mm height, 152 mm depth — define the enclosure cutout and the spacing to adjacent components. Minimum clearance requirements: 10 mm upwards, 20 mm forwards, 10 mm downwards, and 10 mm at the side. These clearances handle arc venting and cooling airflow; crowding them derates the switching capacity. Mounting position is standing on a horizontal surface — the contactor is not rated for vertical or inverted orientation without derating the thermal budget.
Wire Termination and Auxiliary Contacts
Main power terminals accept solid wire from 2.5 mm² up to 16 mm², and stranded wire from 6 mm² up to 70 mm². The magnet coil uses screw-type terminals — no spring-cage option on this variant. A built-in auxiliary switch is included (10... 2 configuration for main contacts). Auxiliary contact wiring accepts 2x (0.5... 1.5 mm²) or 2x (0.75... 2.5 mm²) solid or stranded wire. The auxiliary contacts are rated for 10 A at 24 V, 2 A at 48 V, 2 A at 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, and 0.8 A at 440 V — covering PLC-level feedback and interposing relay loads.
Duty Ratings and Switching Rates
Rated 77 A at 480 V and 15 hp at 230 V — this is the AC-3 motor switching rating. The contactor handles resistive loads (AC-1) at up to 900 switching operations per hour, squirrel-cage motors (AC-3) at 1,000 ops/h, slip-ring motors (AC-2) at 400 ops/h, and plugging/inching duty (AC-4) at 300 ops/h. The AC-3e rating for energy-efficient motors is also 1,000 ops/h maximum. Operating time on AC is 10... 21 ms, with an arcing time of 10... 20 ms. The power factor at 50 Hz is 0.38 — this affects the contact erosion rate in inductive loads. Mechanical life is 10,000,000 operations typical. Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C. The 60 °C ceiling means the contactor can sit in a non-air-conditioned panel in a factory hall, but the switching rate must be derated above 40 °C per the Siemens application manual.