Cause of voltage drop at power point ?

[CompoSimmonite]

Previous owner of daughters terraced house was a bodge expert. Last night she rang me to say the power point that fridge and freezer plug into doesn't work. Checked it out today and it's getting just 166v. Tried changing breaker in fuse box but made no difference. 240v coming out of the breaker so there is a problem between it and the power point. The wiring in the fuse box is black and red however the power point had the later brown and blue wire so assume there is a junction somewhere under the upstairs floor. Told daughter that she will have to get an electrician but am still intrigued at what would cause a 70+ voltage drop. Any suggestions ?

 

[sako243]

Is there anything else on the spur? Disconnect everything and see if it's still the same.

Possibly a dodgy wire with high resistance but also possibly something pulling too much current through an underspecced wire.

 

[brightspark]

could be the jointbox with loose terminals and the cables arking across and carboned up . its a floorboard up job and trace the cable

 

[minimutly]

Is there anything else on the spur? Disconnect everything and see if it's still the same.

Possibly a dodgy wire with high resistance but also possibly something pulling too much current through an underspecced wire.

This would have to be a big load and a tiny tiny (getting hot) cable. I’d suspect a burnt junction somewhere - needs finding asap!

 

[brightspark]

what size breaker feeds it and is there definately nothing else on the circuit

 

[CompoSimmonite]

Power point was working fine for last couple of years but when daughter came in from work yesterday found it wasn't working. Nobody had messed with the wiring or disturbed anything since daughter and partner bought the house. Just two wires going to the breaker so assume that is the ring circuit. Went around the house and couldn't find any other power points on the same 32amp breaker. I said I wasn't willing to get involved further and they need to get an electrician - which they are going to arrange tomorrow.

 

[JimmyS]

Loose terminals overheating in a junction box or earth fault possibly. Have to trace cable.

 

[minimutly]

Loose terminals overheating in a junction box or earth fault possibly. Have to trace cable.

Earth fault? Explain that one please?

 

[dobbslc]

Loose connection somewhere I'd say, try testing from live to earth then live to neutral then at least you know what to look for. I'd go round all the sockets on that circuit just checking the terminals as it might just be one of them that's loose, thats easier than ripping up floors.

 

[brightspark]

difficulty is its a spur so will probably be a jb under the floor. op recons its on a ring but no other sockets on the circuit

 

[JimmyS]

A fine example of wiring discovered here buried in a flat roof which caused similar problems.

 

[Dee J]

Digital meters can register ghost voltages on open circuits. Chances are there's a complete open circuit somewhere.

 

[barracuda816]

Just a quick check but did you measure at the cables into the socket or the socket it’s self? Could be a burnt up socket if you are lucky?

 

[Robotstar5]

A fine example of wiring discovered here buried in a flat roof which caused similar problems.

View attachment 368080 View attachment 368081

Haven't seen a wirenut used in a while

 

[brightspark]

Haven't seen a wirenut used in a while

porcelain screwit

 

[JimmyS]

The photos not great but the cable on the far left in the Henley block had been getting a bit hot due to bad connection. Wiring in here has been amazing in the the sheer range of messes just waiting to go on fire lol. I'd never seen anyone manage to wire a domestic lighting cct in 2.5mm, cut the cable short and just bend the wires so The line up with the terminals and just dispense with the terminal screws altogether.

 

[Guineafowl]

Digital meters can register ghost voltages on open circuits. Chances are there's a complete open circuit somewhere.

That’s what I thought. Try the meter on the LoZ setting if it has one, but in any case you’ll have to find the bad junction or rewire the circuit.

 

[zeppelin builder]

Previous owner of daughters terraced house was a bodge expert. Last night she rang me to say the power point that fridge and freezer plug into doesn't work. Checked it out today and it's getting just 166v. Tried changing breaker in fuse box but made no difference. 240v coming out of the breaker so there is a problem between it and the power point. The wiring in the fuse box is black and red however the power point had the later brown and blue wire so assume there is a junction somewhere under the upstairs floor. Told daughter that she will have to get an electrician but am still intrigued at what would cause a 70+ voltage drop. Any suggestions ?

next door neighbours weed farm