Handheld smart simulator for in situ testing of MCB and switch gear

摘要

Electrical wiring systems are being reported as causes of initiation of fire in residential and commercial establishments. Electrical appliances in these establishments like houses, hotels, hostels or hospitals etc. are predominantly low tension single phase driven loads. These applications normally distribute power through single core wiring system protected by miniature circuit breakers (MCB). These MCBs are only devices in wiring system relied upon to de-energise the partial or entire system before onset of overheating leading to fire. A factory calibrated MCB of a new system can be relied upon. However, over the duration the protection system degrades gradually on its own or due to un-engineered modifications and ability to detect or isolate overcurrent is reduced or lost. Analysis of electrical fire events attributes various reasons ranging from user negligence to design inadequacy. However in many cases the spread of fire outside electrical system precedes with failure of the protecting MCB to detect and isolate the overload or short circuit condition. This paper proposes a periodic testing procedure and an instrument to ensure MCBs are ready to detect the fault and de-energise the circuit.