Faulty time clock circuit

[Dm7192]

Recently i was called to a breakdown where i came across a fault that untill now im not 100% sure what was going on. i checked between live and earth at the load end of the final circuit and got 230V but only 50V between live and neutral, the circuit was protected by a 20a type b mcb however when i connected the feed in to a different 20A type b mcb it worked fine and i was getting 230v between l&n so ruling out a neutral fault and if i got 230 between l&cpc originally surely this would rule out a faulty mcb? any knowledge would be greatly apprecitated.

 

[JD6400]

Was it a 3 ph board , when testing was the circuit under load and did you test between n&e ?

 

[Dm7192]

no it was a single phase Db, the load was disconnected at this point and when testing betweem earth and neutral there was no voltage or anything present so everything seemd fine

 

[JD6400]

Had a wee snip of brandy now so that don't help but i am stumped all the same ?
Sorry chap , but i would love to know this one myself !

 

[Geoffsd]

when testing between earth and neutral there was no voltage or anything present

Was there continuity between N & L?
Not sure if this would solve anything - just thinking.

 

[Dm7192]

no was no continuity between l&n

 

[malcolmsanford]

If you had no continuity between L/N then how did it work when you swopped it over onto the other MCB ?

It seems to have the hall mark of a classic dropped neutral, as that 50v could be there from under circuits under load and as the neutrals are commoned on the bar yuor geting this.