Only 200 Volts at DB

[Guest 004]

Hi peeps

I have just tested my friends house, which has a 3 phase supply, but there is only 200Volts per phase (about 202 measured). So should we contact the local leccy board and ask them to upgrade the cables to accomodate the Volt Drop? or what else can we do?

 

[Spa Key]

Hi peeps

I have just tested my friends house, which has a 3 phase supply, but there is only 200Volts per phase (about 202 measured). So should we contact the local leccy board and ask them to upgrade the cables to accomodate the Volt Drop? or what else can we do?

Is that under any load? How far away from the service head is the DB?

 

[Guest 004]

That was measured at the DB.

Difficult to tell how far from the transformer, possibly too far though

 

[Spa Key]

That was measured at the DB

Again, how far away from the service head is the DB? Was there any load when you were testing?

Edit: Not the transformer. How far away from the main incomer? Where the meters are?

 

[Guest 004]

Yes some load??

cannot locate the service head

 

[Spa Key]

Yes some load??

cannot locate the service head

The amount of load is important. If you can't locate the service head then it's difficult to say anything.

Has this house been built in the back yard of another house and his supply is a submain from the main house? You really need to find the service head.

 

[UNG]

What is the phase to phase voltage also are your readings phase neutral or phase earth

 

[Guest 004]

OK need to add, that it is a TT system, and also we have located the transformer, about 100 metres outside, and also located the intake. Voltage still the same (202 V) between phase and neutral, and phase and the earth rod.

I did not measure between phases, as it more of a visual test, than a full inspection.

 

[UNG]

I did not measure between phases, as it more of a visual test, than a full inspection.

Can't understand if it was a visual test why you were measuring voltages and why you did not check the phase to phase voltage if you checked phase neutral

Have you checked the loop resistances as this may identify or narrow down where the fault is

 

[Guest 004]

I was only there with my voltmeter. I was actually checking something else at the time, do not need to go into that.

Anyway my concern is why the voltage is so low. (Phase - Neutral)
I was not concerned with EFLi, or the integrity of the earth.
I cannot see how a loop test will help with the low voltage?

Even if I was getting 50 ohms, I would be happy with the fact that the main RCD would still trip in the required time.

I am missing something here?

 

[UNG]

Obviously !!

 

[Guest 004]

Obviously !!

A little enlightenment would be nice

 

[pevvers]

A loop test will show you whether you've got a satisfactory earth, if not, this could be the cause of the excessive volt drop as the earth that you are referencing your voltage to be dodgy... If the neutral to line voltage is also 200ish volts then it may be a problem with the supply. If it's normal from line to neutral then I suspect it's a dodgy earth.... Just some things to investigate,

 

[Guest 004]

as previously stated it is a TT system. Although the earth rod has not been measured, the fact that I am getting a voltage between the earth rod and phase, would suggest that the earth was good enough. (1667 ohms ), although the regs state anything above 200 ohms would be unstable.

The fact that I am getting 200 V between P - N, (under load) would suggest to me something is definitely wrong with the supply. Anyway I am due back there soon, and will measure EFLi. Voltage between P - N, P - E (no load), and P - P