Electricians - tell me about circuit breakers please

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I've decided to change my old fuses for some new fuses but I don't know which type to use.

There are these which are cheaper - Circuit Breaker

and these which are dearer but what's the difference? - B Curve Circuit Breaker

Obviously if you know a reliable place I can buy online that would be appreciated.

This is my unit -

junctionbox.jpg
 
One you can plug in, the other you can't. The more expensive one is made of two parts you can unplug each other from.
 
Tbh I would bother touching them or trying to replace them at all. I would get a sparky in to replace that whole box becuase it looks a little old and you might not get any breakers to fit it.
 
Tbh I would bother touching them or trying to replace them at all. I would get a sparky in to replace that whole box becuase it looks a little old and you might not get any breakers to fit it.

There are 2 on the left side that were put in 2 years ago and the sparky said there is nothing wrong with the box.
He's on holiday so I can't contact him before you ask.
 
My fuses look like this so which one replaces it? -

oldfuse.jpg

Well, that fuse contains wire that you replace yourself, available from most hardware stores. If you're asking what amp you should be buying, it's impossible to know without knowing what the circuit will power, and even then it's touch and go. Take the existing fuse to a hardware store and maybe he'll be able to spot the gauge of the wire?. Or, stop being so cheap and call an electrician. Is it really worth the risk?.
 
Well, that fuse contains wire that you replace yourself, available from most hardware stores. If you're asking what amp you should be buying, it's impossible to know without knowing what the circuit will power, and even then it's touch and go. take the existing fuse to a hardware store and maybe he;ll be able to spot the gauge of the wire?.

I'm not asking that.
I'm asking what type of fuses do I buy to replace the old type ones, I know the amps of them because you can see them in the picture.
 
If you want to keep your old fuse box and just replace the rewire-able bs3036 fuses with a more modern mcb trip switch you need to use the 2nd link, the more expensive ones which are bs3871's

This would be mostly for convenience with only a marginal safety improvement.

The first one you linked bs60898's are the current standard and would require a new fuse box installing, but this would come with RCDs and would be a significant safety improvement.
 
Whilst we're on fuse boxes.

Are different manufacturers RCD's interchangable? For instance if I have a MKconsumer unit with 2 RCD's each supporting 5 MCB's could I change the RCD's for Wylex ones?

I ask because my RCD's seem to be tripping whenever a light bulb goes which they shouldn't. This is inconvenient but the major problem is the damn things are nearly impossible to reset and I am always worrying I'll break the plastic toggle.

Is this a characteristic of MK RCD's and is it as simple as swapping out the RCD's for a different make.

Sorry to but into anothers thred.
 
You can usually only tell by the Wire itself seeing as so many people don't care about the labelling scheme, I would say get a spark in to fit you an RCD unit as well, though that may cause other problems that exist on your circuits that MCB's wont pick up on (may actually end up costing you more).

Whilst we're on fuse boxes.

Are different manufacturers RCD's interchangable? For instance if I have a MKconsumer unit with 2 RCD's each supporting 5 MCB's could I change the RCD's for Wylex ones?

I ask because my RCD's seem to be tripping whenever a light bulb goes which they shouldn't. This is inconvenient but the major problem is the damn things are nearly impossible to reset and I am always worrying I'll break the plastic toggle.

Is this a characteristic of MK RCD's and is it as simple as swapping out the RCD's for a different make.

Sorry to but into anothers thred.

Depends on the brand, some companies tend to have larger breakers, best thing to do is go to an Electrical store and ask them in there and tell them what you currently have.
 
Whilst we're on fuse boxes.

Are different manufacturers RCD's interchangable? For instance if I have a MKconsumer unit with 2 RCD's each supporting 5 MCB's could I change the RCD's for Wylex ones?

I ask because my RCD's seem to be tripping whenever a light bulb goes which they shouldn't. This is inconvenient but the major problem is the damn things are nearly impossible to reset and I am always worrying I'll break the plastic toggle.

Is this a characteristic of MK RCD's and is it as simple as swapping out the RCD's for a different make.

Sorry to but into anothers thred.

Answer is maybe..

Different brands sometimes have different spacings for the din rail (the bar running across the bottom of the rcd & mcbs) if you can find a brand with the same spacing you can swap it out.

Otherwise you can swap a whole side of the box, so the rcd and 5 mcbs for the same brand to keep the same spacing, or even do the whole box

the rcds are approx £20-25, mcb's are £4-5 each

Current recommendation is not to mix brands in a fuse box tho, but tbh it doesn't really matter AFAIK, just means its not following manufacturers instructions and they wont be tested to work together, but it will be fine.

PS. There are 2 ways of resetting a tripped rcd..

1) Some trip all the way down and you just push them up, simple.
2) Some trip to the middle position and need to be pushed down then up to reset.

Also if it doesn't reset easily and the above isn't the problem, switch off all the mcb's protected by that rcd, then reset the rcd, then turn the mcbs on, should reset easier on some types of rcd.
 
You can usually only tell by the Wire itself seeing as so many people don't care about the labelling scheme,

The OP is nothing to do with the size of the wire.
It is about replacing the old style fuses with the newer switch ones and I've now found them.
 
Think he was talking about a poorly labelled board, that you can make a guess on what circuit is what by the size cable used, so 1/1.5mm lights, 2.5mm sockets, 6mm cooker, 6/10mm shower etc.

You can also guess this by the fuse rating, but you should check the cable size against the fuse rating to make sure its correct.

Not 100% relevant tho i agree:)
 
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