NBSe NBSM7-45L C16 Residual Current Circuit Breaker with Overload Protection,MEM RCBO

1. General description

This unit combines the overcurrent protection of the "MEMGUARD"mcb with an electronic r.c.d capable of high sensitivity operation with special fail-safe features.The unit is ready for installation in"MEMGUARD"SPN type A or type B boards operating on single phase 240V system. The unit provides single-phase protection against overload ,short circuit and earth leakage currents.

2. OVERCURRENT PROTECTION

Overcurrent protection to circuit conductors is provided by thermal and magnetic tripping elements is the line side ,equivalent to the "MEMGUARD"mcb and is available in both M3 & M6 versions.Operating characteristice on overcurrent (the time/current curves)are as for the "MEMGUARD"standard m.c.b..This section of the unit complies with the requirements of BSEN60947-2 for miniature circuit breakers,Short circuit requirements comply with BS4293.

3. EARTH FAULT PROTECTION

The r.c.d elment of the device provides core-balance detecton of the difference between line and neutral currents and amplificaton to provide high sensitivity.

4. OPERATION OF THE TEST BUTTON

This check is made aftor installation with all shields and covers in place ,and requires the MCB/RCD and the main supply switched on Pressing hte button marked "T" on the MCB/RCD applies a simulated earth-fault to the MCB/RCD whichshould trip instantly.
This should be checkde frequently, at least quarterly. If the MCB/RCD fails to trip seek expert advice.

NOTE:
Operation of the test device checks only the correct functoninge of the MCB/RCD at a higher currect than the rated tripping level.This test does not check the integrity of the earthinge system

5. INSTALLATION

1). Fit MCB/RCD unit as required into "MEMGUARD"consumer/distribution board.
2). The BLACK flying neutral supply lead must be connected to the Neutral supply terminal block.
3). The LOAD connections are made to the outgoing terminals of the unit marked 'L"LOAD and "load.
NOTE:The neutr al supply terminal block.
4). High voltage insulation testers must not be used with the unit in circuit.to carry out hv tests disconnect load side cables from MCB/RCD unit and test circuit as normal.