Circuit breaker that keeps tripping - who knows about electrics?

[brightspark]

why cant u acess the breaker ??can it be moved or improved

 

[rtbcomp]

Thanks, but they seem to be the same and neither seem to have the 230 to 230 ones. Any other suggestions before going with RS?

I suppose you could try Ebay.

Bear in mind with an isolating transformer you should be safe from shocks to earth if the neutral is left floating, however an RCD on the output wouldn't work.

If you want an RCD to trip if the item you are testing has an earth leakage fault then you should earth the neutral on the secondary, but this means the live output will present a shock hazard.

An RCD on the input won't trip if you connect faulty equipment to the secondary.

 

[Bill Edwards]

No possible way of moving the breaker, which is why I tried installing something that should be of a lesser value in a convenient place with no success.

If I'm reasonably safe without an RCD that'll do me.

 

[brightspark]

u realy havent given enough details as how to solve the problem. eg is it actualy an rcd or a mcb back at source is in an ajoining property if rcd how many milliamp /.. 30 ma and what else does it feed if nothing it could be upped to a 100ma slow trip and a 30ma put further down line

 

[Bill Edwards]

That's part of the problem. I don't know what the rating is, or what it actually is - and there isn't any way that I can access it to find out. Anything I do to try and put in something more sensitive is a stab in the dark and so far hasn't worked, and I'll have trouble if it trips again.

 

[rtbcomp]

......

If I'm reasonably safe without an RCD that'll do me.

You'll still need to protect the secondary so faulty equipment doesn't damage the transformer.

 

[Ed.]

About 5 years ago I had an RCD that occasionally and randomly tripped but mainly at night, after a while it started to trip about 6 to 8 times a night and sometimes during the day as well, so you can imagine how much sleep I got, anyway couldn't find any faults. Called in a sparky who tested everything, and again everything was working as it should. Finally called in the power supply people who tested everything and they said the same, but just before they left they said to just change the RCD, as it may have become overly sensitive. Best $40 I have ever spent, no more waking up multiple times to go outside to reset the thing.

Cheers

Ed.

 

[AndyStobbs]

A little sideways, but could you get a small generator to do the initial test on the component, if its shows a dead short on that well you know its got a dead short, if it doesn't show a dead short you could do further testing on the mains taking advantage of cheaper and cleaner electricity.

 

[rtbcomp]

That's a bit OTT - a fuse would give the same indication.

 

[Cyberprog]

Isolation Transformer or a Car Battery + Inverter would suffice I think.

 

[AndyStobbs]

That's a bit OTT - a fuse would give the same indication.

O.p says sometimes his fuse blows, sometimes not, also sometimes the inacessable breaker trips.

Would need to be a hefty inverter for 10A at 240v

 

[rtbcomp]

We don't know if the breaker/fuse that trip supply other circuits, or what different loads are being tested, so a fuse may or may not blow depending on circumstances.

A dedicated fuse on the secondary of the transformer could be tailored to the load under test.

 

[BrokenBiker]

you could have a simple board connected to the secondary of the transformer to allow you to pick and choose what mcb you need. as said the secondary would need to be wired in a way to allow the rcd to work properly but providing you work safely and are aware of the risks then you should be fine

 

[brightspark]

it still hasnt been stated why the supply breaker cant be got at when clearly all fuse gear must be acessible or it dont comply .everything sugested is pie in the sky and a total waste of time just get to the root of the problem and sort it

 

[rtbcomp]

..........everything sugested is pie in the sky and a total waste of time ........

No, this is for a test bench, he needs local protection that is accessible, appropiate for the device under test and doesn't affect anyone else if it trips.

 

[Bill Edwards]

Yes, it's a case of I can't readily access it - somewhere I can't enter.
But it looks like an isolation transformer will solve the problem once and for all, coupled to a B10 circuit breaker so it can't be damaged.