Consumer Unit Bus-bar M.C.B. reliable clamping.

davezawadi (David Stone): 
 

If you look carefully Z you will see that the busbar connections are a little curious. I don't know why but ….

The fire in that CU was above the MCBs, why was that? It could have been the main switch which is completely missing, but still not as simple as it looks.

Indeed Dave, the prime suspect seems to be the main D.P. switch. Also the M.C.B.s did not burn, it was mainly the P.V.C. insulated cables. 

I once came across a 40 Amp M.C.B. that had not gripped its bus bar finger securely as the cage was positioned incorrectly. There was no sign of heat damage. I assumed that the short usage of the shower did not allow sufficient time for a dangerous build up of heat.

I have just been working on an old Crabtree C50 dis. board. What a great reliable design with proper visible screws to secure the M.C.B.s to the bus-bars. A wonderful reliably clunky old British design and manufacture.

CRABTREE 5 AMP SINGLE POLE/PHASE MCB CIRCUIT BREAKER 5A C-50 OLDER STYLE BS3871 | eBay

Z.

davezawadi (David Stone): 
 

If you look carefully Z you will see that the busbar connections are a little curious. I don't know why but ….

The fire in that CU was above the MCBs, why was that? It could have been the main switch which is completely missing, but still not as simple as it looks.

Indeed Dave, the prime suspect seems to be the main D.P. switch. Also the M.C.B.s did not burn, it was mainly the P.V.C. insulated cables. 

I once came across a 40 Amp M.C.B. that had not gripped its bus bar finger securely as the cage was positioned incorrectly. There was no sign of heat damage. I assumed that the short usage of the shower did not allow sufficient time for a dangerous build up of heat.

I have just been working on an old Crabtree C50 dis. board. What a great reliable design with proper visible screws to secure the M.C.B.s to the bus-bars. A wonderful reliably clunky old British design and manufacture.

CRABTREE 5 AMP SINGLE POLE/PHASE MCB CIRCUIT BREAKER 5A C-50 OLDER STYLE BS3871 | eBay

Z.