ELCB

[gordy71]

Yesterday i had a job to wire up a new dual fuel cooker. The installation was TT with an old elcb so i put a 30ma rcd on my circuit. This all went fine and whilst i was there i did the customer a 'favour' and removed a dodgy socket that had been extended to be mounted on the outside of some built in wardrobes with exposed terminals on the inside of the cupboard. All i did was remove it and replace it back to its original position where there was currently a blank plate. In doing so i managed to wire up the socket wrong with the live and earth the wrong way round! :| I turned the power back on whilst i was having a tidy up and thought nothing of it. 10 minutes later the customer plugged the hoover in and the elcb tripped. Why did it not trip as soon as i put the power back on? Is it because the elcb is voltage operated and did not recognise the flow of leccy till the hoover was switched on or would it have been seized with it not being operated for a few years? cheeeers

 

[Andy™]

there would probably not have been any current flowing to earth until something was connected to that socket

 

[mikep]

I agree with Andy.

No fault on socket until a load is connected how you have wired it so no trip, Normally the earth pin on a hoover has no connection to the appliance " 2 wires only to hoover L+N" so you have now connected load between CPC + Neutral with a bit of differential across them or inductance enough to produce a bit of juice, ELCB see's fault when hoover switched on. trip occurs.

Mike.

 

[batty]

so was it voltage operated ie one with the big yellow button or current operated ie RCD whatever it was it probably will not work until you plug something in anyway how come you didn't loop test it?

 

[mikep]

He was just taking the extended part away and C***** it up as we all do sometimes Batty !!

 

[gordy71]

I get the bit about it not having an earth path but the elcb (big old black thing with yellow test button) didnt trip till the hoover was plugged in at a different socket. After that it continually tripped. I can only put it down to it being seized. Would the mass of the wall where the back box was act as earth? Yes batty i tested zs before i removed it and checked continuity of the ring. Lesson learnt though, testing after is essential to identify stupidity!

 

[thebantam]

In doing so i managed to wire up the socket wrong with the live and earth the wrong way round!Lesson learnt though, testing after is essential to identify stupidity!

Tut tut, thats why i always carry my 'socket and see' with me! lol

 

[m4tty]

Does socket n see show neutral earth faults. Don't think mine does?

 

[philbas]

No it won't show neutral earth faults, but in this case we have a live earth fault, so yes it would have shown it

 

[gordy71]

Tut tut, thats why i always carry my 'socket and see' with me! lol

Lol, suppose you wear it on ya belt do ya?

No offence but what is the point of a socket and see? Dont they only tell you polarity and if the earth loop is <1,<100. Why not just a proper multifunction and a plug in polarity? Mind you like you say i could have done with one:coat

 

[steptoe]

mine makes a whining sound (bit like the missus!)so good for isolation purposes,

you can hear it bleeping so know when you have pulled the right fuse,

still do a test on it though just to be sure.

 

[batty]

socket and see will tell neutral to earth reverse if RCD protection is there because when you plug it in it will trip RCD. As for VOELCB they are past there sell by date so shoulde be replaced.

 

[NozSpark]

What about the Crabtree ELCBs that are essentially a current sensing version of the old VOELCBs?

 

[batty]

Not sure what you mean what mA trip are they.

 

[NozSpark]

One like this mate

I know this is a 500mA version, but I'm sure I've seen a 30mA one

 

[batty]

Take it has a cover somewhere. Well if your tester can test at 500mA then you could test it and see if it works. It does look pretty ancient maybe a museum would be interested in it.

 

[Andy™]

the covers are usually dull green. often take these out

 

[batty]

What on a date.

 

[Andy™]

What on a date.

yes, but they keep falling off. very hard to balance it on one of these

 

[NozSpark]

Take it has a cover somewhere. Well if your tester can test at 500mA then you could test it and see if it works. It does look pretty ancient maybe a museum would be interested in it.

Oh,,, yeh, it did have a cover

I removed it during a CU change.

It is a VOELCB with a current sensing coil attached