Selective main MCB for service entrance coordination
It is designed for use as a main breaker in residential and infrastructure distribution boards, providing selectivity (discrimination) with downstream MCBs so that only the faulted branch trips during a short-circuit or overload event. The E-curve magnetic trip threshold is set higher than a standard B or C curve, allowing it to ride through inrush of downstream devices.
Terminal capacity and wiring range
The 5SP3725 accepts solid conductors from 2.5 mm² up to 50 mm² and stranded conductors from 2.5 mm² up to 70 mm². Saddle terminals are standard, providing a secure clamp for larger cable sizes often encountered at the main breaker position. Occupies 2 width units on the rail. Depth of the enclosure is 92 mm.
Shock resistance is 30 g for at least 3 impacts with 11 ms duration per the test standard. Vibration resistance per IEC 60068-2-6 is 2 g over 20 frequency cycles from 5 to 150 Hz. Mechanical service life is 20 000 switching cycles typical. Overvoltage category IV — suitable for the service entrance where the breaker sees the highest transient overvoltages from the utility grid. Insulation voltage rated at 690 V.