test meters

[telectrix]

interesting. might be worth a punt here:
Electrical Test Meters | eBay

 

[Richard Burns]

Probably worth it for the leads!
I would not give much for the meters unless I had the same model.

 

[GLENNSPARK]

well i`v just bought an old seaward RCCB tester ....old but unused...

i`ll chuck it in with the pat testing gear...

i`m gonna make up an isolator for testing RCDs using socket outlets that are already on an RCD...

isolating tranny out of a shaver outlet with a neutral-earth link secondry side should do it...

 

[PEG]

Hi Glenn,will that set up be solely for 30 Ma testing,and does any provision need to be made for the squirting of current down the cpc backside of the tranny? ....crikey,that went a bit "carry-on"...:38:

 

[GLENNSPARK]

Hi Glenn,will that set up be solely for 30 Ma testing,and does any provision need to be made for the squirting of current down the cpc backside of the tranny? ....crikey,that went a bit "carry-on"...:38:

well think about what an isolating transformer is:

theres no reference earth on the secondry side....current will flow between 2 reference points yes....

so as the installation`s CPC ends at the incoming side of the transformer....and does not carry through...and of course you also have electrical seperation between the primary...and secondry windings....so there can be no reference between the starpoint & earth or neutral on secondry.

now, you need to create a reference for the test instrument to start injecting fault into from the phase (secondry)....so as theres no reference earth on the secondry side what you can do is create one by introducing a neutral-earth link....secondry side...

this will provide a path for simulated fault currents in mA...which will take out the RCD being tested....this would be any RCD connected secondry side.....and as theres no throughpath for leakage....the top end RCD will not see any leakage....caus it wont be there...will it.

Hope this explains things a bit.

Glenn.

 

[PEG]

...Just cancelled a rambling text,been shooting all morning and head is fuzzy....no probs,was confusing myself due to problems encountered years back making test rigs for MIG/TIG equipment,where we used separation transformers but ALSO required ground/earth connection,this being derived from source of circuit. This raised voltage on cpc and "upset" other gear on that circuit,and dedicated 6mm connection to MET was run in solely for this testing...cheers,PEG

 

[Dizzy_Maskell]

Has someone asked the police who's van has been stolen,
Looks like worth a bid defiantly but now tel by putting it on you may have cost yourself some competition lol

 

[Aindowsimon]

well think about what an isolating transformer is:

theres no reference earth on the secondry side....current will flow between 2 reference points yes....

so as the installation`s CPC ends at the incoming side of the transformer....and does not carry through...and of course you also have electrical seperation between the primary...and secondry windings....so there can be no reference between the starpoint & earth or neutral on secondry.

now, you need to create a reference for the test instrument to start injecting fault into from the phase (secondry)....so as theres no reference earth on the secondry side what you can do is create one by introducing a neutral-earth link....secondry side...

this will provide a path for simulated fault currents in mA...which will take out the RCD being tested....this would be any RCD connected secondry side.....and as theres no throughpath for leakage....the top end RCD will not see any leakage....caus it wont be there...will it.

Hope this explains things a bit.

Glenn.

At risk of sounding a bit green here . I like the idea where is it to be implemented ?

 

[GLENNSPARK]

At risk of sounding a bit green here . I like the idea where is it to be implemented ?

well....its for PAT testing RCD extention leads....:

say you are in someware....and all socket outlets are on a 30mA RCD....so it stands to reason doesn`t it that if you plug in an RCD extention lead....then you would have effectively 2 30mA RCDs in series...now, as the RCD protecting the socket outlets will/may be already being subjected to a certain amount of earth leakage...any attempt at testing the RCD extention lead will result in taking out the top end RCD (socket outlets)....so the way forward is to isolate this from any fault currents from the RCD tester...

do you see now?

here:

its either this for 70 odd quid:






or this for pence:







take your pick....

 

[SPARTYKUS]

Glenn

do you mean

" either get mugged off or make your own"

 

[Aindowsimon]

Thank you clearing that up . I don't do any pat testing , I never even did it college work wasn't willing to release me from work for the course
But I like your solution and now I know were it's implemented makes obvious sense

 

[GLENNSPARK]

Glenn

do you mean

" either get mugged off or make your own"

thats about the level of it.....

 

[UNG]

I have a similar set up in a small transformer box (looks like a 110v transformer) I mainly use it for testing RCD's in caravans