# Electrical Surge Woes



## twentysix by twentyfive (30 Jan 2020)

Recently I bought an electric chainsaw. It's rated at 2kW so 8-9 amps I think. The circuit I plug it into has a 16A MCB protection at the Consumer Unit and yes that's correct as it is on a spur. However the MCB does trip out sometimes (but not always) on startup. Is there some sort of start up surge protection I can fit which will suppress the surge such that the MCB won't trip? It's a bleeping nuisance. I could run an extension cable from a 32A MCB protected ring main circuit but Mrs 26 would complain of cold draughts through open doors.


----------



## the snail (31 Jan 2020)

One thing you can try is plugging into a coiled up extension lead.


----------



## Phaeton (31 Jan 2020)

the snail said:


> One thing you can try is plugging into a coiled up extension lead.


I have no idea but that does not sound like a good idea to me, I once inadvertently used a welder with a coiled up extension lead, it melted all together.

You could probably change the MCB for a slow blow one that is not the technical term, but it won't trip immediately it allows a small amount of time before blowing. Is it s well known manufacture? If so it might be worth contacting technical support & explaining the issue, it might be a faulty unit.


----------



## the_mikey (31 Jan 2020)

Check the letter rating of the MCB, Ideally a type C or D MCB is needed for power tools, some motors have multiple windings with one of them intended to be a start up winding which uses more current initially to get the motor turning.


----------



## twentysix by twentyfive (1 Feb 2020)

Thanks all. No letter on my MCB. It's one of these




. I'll off to the supplier and ask. 

I had been running it on a coiled up extension lead (purely for ease and not as a fix) but that started to trip the RCD and turn the whole house off. So the extension lead needs a look see too.

Thanks gang


----------



## bruce1530 (1 Feb 2020)

Disclaimer: speak to a qualified electrician. A sensible one if you can find one.

Type 1 MCBs are obsolete - the new common classifications are types B/C/D. A new “Type B” is broadly similar electrically to a “Type 1”.

For loads which are moderately inductive (ie motors) a type C is more appropriate,

Disclaimer: see disclaimer above.


----------



## irw (1 Feb 2020)

the snail said:


> One thing you can try is plugging into a coiled up extension lead.



Sorry snail, but this is very poor advice! Coiled extension leads have a much lower rating than uncoiled leads, and, as @Phaeton alluded to, has a very real danger of causing a fire.


----------



## Notafettler (3 Feb 2020)

irw said:


> Sorry snail, but this is very poor advice! Coiled extension leads have a much lower rating than uncoiled leads, and, as @Phaeton alluded to, has a very real danger of causing a fire.


I have never had problems using a coiled up extension lead. Every time you take your finger off the trigger the motor stops. It is stopped far more than it's running as I am loading wood onto a saw horse, start chainsaw 2 cuts, chainsaw stops, load more, etc. Then load wheelbarrow move to woodstore and stack. Doubt it is running for a quarter of the time I am using it.


----------

