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Siemens 5SM3644-4KK14 — Residual Current Breakers (RCCB/RCBO)

5SM3644-4KK14 SENTRON RCCB, 4P, 40 A, 300 mA, Type B+, 10 kA

MPN5SM3644-4KK14

Siemens SENTRON 5SM3644-4KK14, 4-pole RCCB, 40 A, 300 mA, Type B+, short-time delayed, 10 kA SCCR, 4 MW, DIN rail.

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

Specifications

5SM3644-4KK14 — Electrical Ratings
ParameterValue
Number of poles4
Overvoltage categoryIII
5SM3644-4KK14 — Identification
ParameterValue
Product designationRCCB
Product design / constructionShort-time delayed
5SM3644-4KK14 — Mechanical
ParameterValue
Mounting positionany
Width in modular units4
Maximum45 °C
Minimum-25 °C
Width72 mm
Height90 mm
Depth77 mm
Installation depth70 mm
5SM3644-4KK14 — Environmental
ParameterValue
IP degree of protectionIP20, if the distribution board is installed, with connected conductors

Product details

It's short-time delayed (selective S-type), so it coordinates with downstream RCCBs: the fault clears at the nearest device first, not nuisance-tripping the main.

40 A continuous at 40 °C ambient; at 50 °C it derates to 38.4 A, and at 70 °C to 32 A — so if the panel runs hot, the nominal load must stay under the derated curve. The 10 kA short-circuit current rating (SCCR) per IEC 61008-1 means it safely interrupts faults up to that level; the I²t let-through is 70,000 A²·s, which the upstream breaker must be coordinated to handle. Surge current resistance is 3 kA (8/20 µs waveform) — important for lines with lightning exposure or capacitor switching. The 300 mA residual trip is a standard for equipment protection (not personnel shock), typically used on branch circuits feeding fixed machinery or sub-distribution boards. Type B+ extends coverage to smooth DC fault currents up to the rated frequency — a requirement for modern power-electronics loads that generate DC leakage. Installation depth behind the panel is 70 mm.

Frequently asked questions

What is the 5SM3644-4KK14 used for?

It is a 4-pole Type B+ RCCB used for equipment protection on circuits with VFDs, UPS systems, or PV inverters that generate smooth DC fault currents. The 300 mA trip and short-time delay make it suitable for sub-distribution boards where selective coordination is needed.

Where can I buy 5SM3644-4KK14?

This part is sourced and quoted to order against an RFQ through independent distribution channels. Availability and current pricing are confirmed at the time of quotation.

MPN
5SM3644-4KK14