Residential Sprinkler Pump Protection

Others here will know better than me - but certainly the requirement for fuses rather than MCBs on fire safety circuits is a common one.


The solution will depends somewhat on the size of circuit - some manufacturers offer MCB-sized HBC fuse carriers which you could probably swap the MCB for - which might do you up to about 32A. Above that they tend to be supplied as ready assembled switch-fuses (sometimes with a DIN-rail mounted fuse holder - often 1.5 or 2 'modules' wide, sometimes something more bespoke). Larger DIN-rail fuse carriers are available separately, but you then tend to run into BS EN 61439  issues about becoming an assembly manufacturer and having to type test the completed assembly etc.


   - Andy.

Best of luck buying fuse holder for a domestic consumer unit.

Just out of curiosity, why are fuses preferred over circuit breakers?

Fuses are very, very, reliable. MCBs are just very reliable - and in principle an MCB might have had a full current trip event in the past, and be in some way weakened, and you cannot tell from outside.

Generally the idea here is that the pumps are certain to keep turning right to the last possible moment. -  if required that includes while the burning building pretty falls down around them.

Mike.


PS

DIN rail fuses are common enough - we just need UK  CU manufacturers to be a bit less restrictive about stuff made by others in their enclosures magically making it unsafe.

 

On the continent Neozed and Diazed bottle fuse holders are often seen as part of a domestic DIN rail fuseboard - sometimes as the main incoming let-through energy limiting element.

Those bottle fuse holders pictured on the right - can the fuses be withdrawn without a tool?

Yes they can be removed without a tool, and the live contact which SHOULD be the base can then be touched.

In the UK they should therefore be in an enclosure that requires a key or tool to open.


One merit of such fuses is that an ES base lamp can be inserted in place of the fuse. If the lamp lights with all loads turned off, then there is a fault.


Not much used in the UK.

?