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Siemens 3RT1275-6AP36 — Contactors

Siemens 3RT1275-6AP36 SIRIUS Vacuum Contactor, S12, 220-240

MPN3RT1275-6AP36
Active

Siemens SIRIUS vacuum contactor, size S12, 3RT1275-6AP36, 220-240 V rated coil voltage, screw-type terminals, screw fixing, 214 x 160 x 225 mm.

Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

3RT1275-6AP36 — Identification
ParameterValue
Contactor frame sizeS12
3RT1275-6AP36 — Ratings & Performance
ParameterValue
Rated operational current, AC-12, max.10 A
Rated operational current, AC-4 @ 400 V350 A
Rated value @ 400 V3 A
Rated value @ 500 V2 A
Rated value @ 690 V1 A
Rated value @ 230 V6 A
Rated value @ 24 V10 A
Rated value @ 60 V2 A
Rated value @ 110 V1 A
Rated value @ 220 V0.3 A
3RT1275-6AP36 — Control & Coil
ParameterValue
Control supply voltage typeAC/DC
Rated value @ 50 Hz0.9
Rated value @ 50 Hz220 ... 240 V
3RT1275-6AP36 — Contacts & Poles
ParameterValue
Main poles3
Main NO contacts3
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RT1275-6AP36 — Protection & Coordination
ParameterValue
Short-circuit coordination type 1, fusegG: 800 A (690 V, 100 kA)
Short-circuit coordination type 2, fusegG: 800 A (690 V, 50 kA), aM: 630 A (690 V, 50 kA), BS88: 800 A (415 V, 50 kA)
Aux. switch short-circuit protection, fusegG: 10 A (500 V, 1 kA)
3RT1275-6AP36 — Connection & Mounting
ParameterValue
Main circuit connectionConnection bar
Aux. / control circuit connectionscrew-type terminals
Conductor cross-section, solid2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), max. 2x (0.75 ... 4 mm²)
Conductor cross-section, solid or stranded2x (0,5 ... 1,5 mm²), 2x (0,75 ... 2,5 mm²), max. 2x (0,75 ... 4 mm²)
Conductor cross-section, finely stranded w/ ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Mounting methodscrew fixing
Side-by-side mountingYes
3RT1275-6AP36 — Durability
ParameterValue
Durability (operating cycles, typ.)10 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RT1275-6AP36 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RT1275-6AP36 — Mechanical
ParameterValue
Width160 mm
Height214 mm
Depth225 mm
3RT1275-6AP36 — Specifications
ParameterValue
At AC60 ... 100 ms

Product details

The vacuum arc-quenching chamber handles frequent switching without contact erosion, making it suited for applications like conveyors, pumps, and compressors that cycle heavily. The coil is rated for 220-240 V AC/DC, with a pick-up threshold of 0.8x rated value and a drop-out at 1.1x full-scale value, meaning it holds in reliably across a sag to about 176 V and releases cleanly above 264 V. Mechanical life is rated at 10,000,000 operations typical, and the contactor can sustain operating rates up to 750 cycles per hour in AC-3 duty (motor starting) and 250 cycles per hour in AC-4 (plugging/reversing).

Auxiliary contact ratings: 10 A at 24 V, 2 A at 48 V, 2 A at 60 V, and 1 A at 110 V. These are the make/break capacities for the control circuit — a 24 V PLC output driving a relay or a 110 V interlock both fall within range, but the 110 V limit means you cannot switch a 2 A 110 V load on this auxiliary contact. Power wiring accepts stranded conductors from 70 to 240 mm², while the coil and auxiliary wiring accept solid or stranded from 0.5 to 4 mm². That covers main motor feeders up to about 300 A and control wiring down to 20 AWG. Mounting is by screw fixing with one 11 mm hole. That flexibility helps when retrofitting into existing enclosures where the backplate is already drilled.

Dimensions and clearances

The contactor measures 214 mm high, 160 mm wide, and 225 mm deep. These clearances ensure adequate air circulation and arc-quenching space — a panel builder should account for them when laying out the gland plate and busbar runs.

Frequently asked questions

What are the key dimensions of this contactor?

Height 214 mm, width 160 mm, depth 225 mm. Minimum clearances: 10 mm up/down/sides, 20 mm forward.

What wire sizes does the 3RT1275-6AP36 accept?

Main power terminals accept stranded 70-240 mm². Coil and auxiliary terminals accept solid or stranded 0.5-4 mm² (2x 0.5-1.5 mm², 2x 0.75-2.5 mm², max 2x 0.75-4 mm²).

What is the operating temperature range?

During operation: -25 to +60 °C. During storage: -55 to +80 °C.

How does this compare to the 3RT1076-6AP36?

The 3RT1076-6AP36 is a similar SIRIUS vacuum contactor but in a smaller frame size (S10 vs S12). The 3RT1275-6AP36 has a larger footprint (214x160x225 mm vs the S10's smaller dimensions) and accepts larger main conductors (up to 240 mm² stranded vs the S10's lower capacity). If your panel was designed for the 3RT1076-6AP36, the 3RT1275-6AP36 will not drop in without drilling new mounting holes and checking clearance for the larger envelope.

MPN
3RT1275-6AP36