SIRIUS Size S2 power contactor — 3RT1036-1AL24-ZX95
The Siemens 3RT1036-1AL24-ZX95 is a SIRIUS-branded power contactor in the Size S2 frame, designed for switching motor loads and resistive circuits in industrial control panels. It carries a rated operational power of 22 kW at 400 V in AC-2 duty (slip-ring motor starting), and 30 kW at 500 V — the rating that governs the real motor load it can handle. The contactor mounts on a 35 mm DIN rail per DIN EN 50022, using either screw-fastening or the integrated snap-on clip, and fits a 55 mm wide slot in the enclosure.
What the ratings mean for fit
AC-2 at 400 V rated 22 kW — that is the duty for wound-rotor motors where the contactor makes and breaks at reduced current but must handle the full load continuously. The AC-3 rating (squirrel-cage motors, direct-on-line start) is the more common benchmark; this Size S2 frame typically covers motors around 18.5–22 kW at 400 V depending on the specific variant. AC-1 resistive load switching is rated at 1000 operations per hour maximum, while AC-4 (plugging/inching) is limited to 300 1/h — so if your application involves frequent reversing or jogging, the mechanical life of 10 million cycles is not the limiting factor; the electrical endurance at AC-4 is. The auxiliary contact ratings cover the coil circuit: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V. These are the make/break capacities for the contactor's own control coil and any auxiliary contacts in the same block — useful when coordinating with a PLC output card or a control transformer. Terminals are screw-type on the main circuit, accepting solid conductors from 2x 0.5 mm² up to 2x 4 mm², and stranded from 2x 0.75 mm² up to 2x 25 mm². The control circuit terminals accept 2x (0.75... 16 mm²) solid or stranded. Pollution degree 3 means it is rated for industrial environments with conductive pollution — standard for an uncoated panel contactor. IP20 on the front, IP00 at the terminals: the front is finger-safe, but the wiring zone requires the panel enclosure to provide the IP rating.
Mounting and integration
Fastens by screw or snaps onto 35 mm DIN rail per DIN EN 50022. Side-by-side mounting is permitted — no mandatory spacing between contactors, which keeps the panel width tight. Dimensions: 55 mm wide, 112 mm high, 164 mm deep. The depth is the dimension that matters when the panel depth is constrained by a shallow enclosure or a rear gland plate. Operating temperature range -25 to +60 °C; storage -55 to +80 °C. The storage limit is the handling and logistics boundary — the contactor can sit in a cold warehouse without damage, but must be at operating temperature before being energized under load.