Residual Current Breakers with Overcurrent Protection (RCBO)
The one module MK Sentry RCBO s are a combination of a Miniature Circuit Breaker (MCB) and a Residual Current Device (RCD). This protects the individual circuit from both overload and earth fault.
RCBOs are considered a better way of providing circuit protection while reducing the possibility of nuisance tripping in accordance with the wiring regulations.
The operating dolly on all MK Sentry RCBOs may be locked in either the ON or OFF position without affecting the ability of the trip mechanism to operate. The MK Sentry RCBO features tunnel terminals of generous capacity, with 25mm2 for live supply and 10mm2 for live and neutral load terminals. The neutral supply (blue) and earth supply (white/cream) are provided via flying leads.
MK have released a new version of their RCBO. The new 79.. series fits all current MK Sentry boards in the same way that the MK 69.. series RCBO does. Both versions will be available for a short time.

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