230v dropped to 130v - what happend?

[janolsen]

My European socket stopped working after somebody likely tried to sabotage it. It's 4 wires plus ground, so it can do in theory 380v. When I measure the blue wire to white or black, I get 130v and blue to brown is just 67v. Is a fuse broken somehow (not easy to tell with modern fuses)?

All readings should normally be 234v, which is measured on the fuses.

Any idea what can be wrong? Attaching photo of 234v reading, and the wires that yield 67v and 130v.

 

[Geoff1946]

Likely you have lost the supply on two phases. The low voltages you are seeing are probably phantom voltage, (capacitive coupling from the working phase), if you are using a high impedance meter.

 

[SPECIAL LOCATION]

(1) Those test probes do not look like an industry recognised approved voltage tester to me?

(2) I would not want to be using neutral as a reference point for any fault finding.. As neutral is also a Live conductor just as the Line conductors are. And a broken neutral conductor can give strange voltage readings and a significant electric shock to anyone who touches it!!

(3) I would be wanting to use a proven earth reference point with a better voltage tester to see exactly what voltages you actually have or don't have..

 

[janolsen]

The Multimeter used is EU TUV Rheinland approved for up to 300v, sold by a German retailer - ood enough for simple measurements.

Plugged in a phone charger (without using it to charge). Then volt dropped to half, 71v this morning became 29v.

 

[janolsen]

Likely you have lost the supply on two phases. The low voltages you are seeing are probably phantom voltage, (capacitive coupling from the working phase), if you are using a high impedance meter.

Plugged in a phone charger (without using it to charge). Then volt dropped to half, 71v this morning became 29v. So maybe an indication of broken or disconnected wires, can't observe anything wrong - the wiring in the fuse box is difficult for me to interpret fully The 3 MCBs are connected together on the levers as one lever - 3-pole type.

I see no obvious disconnected or broken wires.

 

[janolsen]

Replaceing the cable between fusebox and the socket is the most likely solution it seems...?

 

[Geoff1946]

Absolute guesswork with the information available but I'll stick with my initial guess that the fault is before your "fusebox" and you simply no longer have a three phase supply coming in.
I think you need an electrician.

 

[apprentice87]

Measure the voltages between the brown, the black and the grey and earth [ground] and see what you have.

john..

 

[poni]

take them all out of the top of the MCB and test the Continuity at the socket that will tell you if you have a broken wire or not

Measure the voltages between the brown, the black and the grey and earth [ground] and see what you have.

john..

but do this first to make sure that you have all three lives(phases) also check between the browns for 380V on both sides of the RCD (just check every where there should voltage to make sure you have what you should have) then check for broken cables,

 

[Andy™]

The Multimeter used is EU TUV Rheinland approved for up to 300v, sold by a German retailer -

not wanting to state the obvious, but your 300v multimeter is a little inadequate for the 400v if everything was working fine. probably a good thing it is broken