Brownout? or am i missing something?

[SX2]

Evening all!
Have had a strange problem today my gut is telling me its a brown out! , We are currently working in a old cottage concealing the wiring recently rewired in surface trunking circuit at a time. Around 1500hrs We noticed the lead light (2d) would not start and quickly established a power fault. On investigation I found that as the loading on the system increased the voltage dropped considerably, under no load I was getting around 239v but with around 180watts of incandescent lighting this dropped to 217v turn as 2kw heater on and game over! Everything is rcd with no nuisance trips, all but one circuit is above 50 Mohm with the other at 2.4 Mohm so no problem there! have tried all circuits independently the only common denominator is load. Having never experienced this with a mains system I feel a little stumped. the cottage is remote and at the end of line from the nearest transformer, any thoughts?

Many thanks!

 

[GLENNSPARK]

check tail terminations....both of em...

 

[GLENNSPARK]

had this a while back...
complaint of the lighting working OK...

but as soon as the oven went on...well, it all went off...

traced it to a dodgy termination in the service head....

 

[ruston]

Then your overheads if you have them!

 

[MDJ]

, any thoughts?

!

Plenty, how about you?

 

[Marvo]

If it happens again you need to test the voltage at the head to establish whether it's an internal wiring issue or an external DNO problem. It might be worth putting the installation under some load and see if you can replicate the problem for testing purposes, put the stove, oven immersion heater and any other heaters on and check the voltage difference between the incoming supply and the ends of the circuits.

 

[Darkwood]

Surface trunking in domestic! that must look ghastly :uhoh2:

 

[SX2]

Checked all terms on my side, it is over head so maybe the weather has had something to do with it. Just phoned the customer and they are now able to use more power just not full yet!

- - - Updated - - -

hence why I am there! old owner had rewire on cheap!!

 

[GLENNSPARK]

If it happens again you need to test the voltage at the head to establish whether it's an internal wiring issue or an external DNO problem. It might be worth putting the installation under some load and see if you can replicate the problem for testing purposes, put the stove, oven immersion heater and any other heaters on and check the voltage difference between the incoming supply and the ends of the circuits.

come on marvo..
i expected more from you...
i thought this would be obvious...

 

[SX2]

And Marvo thats what i did!

 

[GLENNSPARK]

And Marvo thats what i did!

so check the busbar is sitting right in the dis-board...
another classic...

 

[SX2]

Split load with separate heating board (old n/s) no matter the combo of load applied out she go's!!

 

[Marvo]

And Marvo thats what i did!

But you say the customer still has a problem this evening.....so you didn't localise the fault or establish if it's a DNO issue. I'm sure you could have found this fault if it was persistent and if you also were persistant

As Glenn says there's a very good chance it's a poor termination or incorrectly fitted busbar that's behind a clamp on an MCB rather than inside the clamp.

 

[GLENNSPARK]

Split load with separate heating board (old n/s) no matter the combo of load applied out she go's!!

start loading it up...check incoming...
check L-N & L-E..
this will determine which one is down...

 

[Earthstore]

Old house??? Probably Ghosts then.....