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Siemens 5SM2645-0 — Residual Current Breakers (RCCB/RCBO)

Siemens 5SM2645-0 SENTRON RCD, 63A 4P 300mA AC Type

MPN5SM2645-0
Active

Siemens SENTRON 5SM2645-0, 4-pole instantaneous RCD, AC type, 63 A rated, 300 mA fault current, 50 Hz, IP20, current production.

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

Specifications

5SM2645-0 — Electrical Ratings
ParameterValue
Number of poles4
Overvoltage categoryIII
5SM2645-0 — Identification
ParameterValue
Product designationRCD-unit
Product design / constructioninstantaneous
5SM2645-0 — Mechanical
ParameterValue
Mounting positionany
Width in modular units3
Maximum75 °C
Minimum-40 °C
Width124 mm
Height90 mm
Depth77 mm
Installation depth70 mm
5SM2645-0 — Environmental
ParameterValue
IP degree of protectionIP20, if the distribution board is installed, with connected conductors

Product details

It's built to trip on sinusoidal AC fault currents at the 300 mA threshold, making it a fit for general-purpose protection in distribution boards where the load side doesn't generate pulsed DC fault signatures — think resistive heating, basic motor circuits with no VFD, or older lighting banks. Rated at 63 A AC and 460 V insulation voltage, it handles a 50 Hz supply across four poles.

Thermal derating — what the 63 A rating actually means in a warm panel

Above that, the device derates linearly: 58.6 A at 45 °C, 56.7 A at 50 °C, 54.81 A at 55 °C, 53.55 A at 60 °C, 52.29 A at 65 °C, and 50.4 A at 70 °C. The -40 °C to 75 °C storage range is wider than the operating derating curve covers.

Snaps onto DIN rail (REG fastening method), occupies 3 modular width units. The IP20 rating applies when installed in a distribution board with conductors connected — so it's a panel-internal device, not for standalone outdoor use.

Frequently asked questions

Where can I buy 5SM2645-0 and get current pricing?

This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for the latest position.

What are the key ratings for 5SM2645-0?

63 A rated current at 40 °C, 300 mA rated fault current, AC type, instantaneous trip, 4 poles, 460 V insulation voltage, 50 Hz operating frequency. IP20 in an installed distribution board.

What is the physical size of 5SM2645-0?

124 mm wide × 90 mm high × 77 mm deep, installation depth 70 mm. Occupies 3 modular width units on DIN rail.

MPN
5SM2645-0