clanky
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Hello.
Im an enthusiastic diy'er and whilst finishing off a job that a local sparky came to do, i came across this 'fault' that i find a bit worrying.
My house is split up into to two section with separate consumer boards fed from henly blocks. When i was rerouting the earth cables for an additional supply i got a mild belt off one of them. Long and short of it after some testing, i found there was around 75 ish V present on the earth line. I disconnected everything and carried out an insulation test (500vdc) on the supply cable (16mm SWA - around 12m long) and all tested good except even with everything disconnected, i was still seeing 30v on the earth when live.
This is between the earth on that particular supply cable and the main incoming earth. Im presuming that this is an induced voltage? I know that this wasn't strictly safe as i essentially had a live supply with no cpc but i felt i needed to investigate this problem and i was as careful as can be.
Further testing on all the individual circuits from that board showed a few adding (around 8v) to the overall problem but i eventually traced the main culprits to the washing machine (40+v) and a dryer (15V). Is this normal? Obviously with all the earth lines connected this problem doesnt actually exist as any residual voltages would be 'drained' and would therefore be undetectable under normal circumstances so am i creating a problem where one doesnt actually exist? Currently my main concern is that the washing machine, being a cheap indesit, could be on its way out and would best be changed.
Im an enthusiastic diy'er and whilst finishing off a job that a local sparky came to do, i came across this 'fault' that i find a bit worrying.
My house is split up into to two section with separate consumer boards fed from henly blocks. When i was rerouting the earth cables for an additional supply i got a mild belt off one of them. Long and short of it after some testing, i found there was around 75 ish V present on the earth line. I disconnected everything and carried out an insulation test (500vdc) on the supply cable (16mm SWA - around 12m long) and all tested good except even with everything disconnected, i was still seeing 30v on the earth when live.
This is between the earth on that particular supply cable and the main incoming earth. Im presuming that this is an induced voltage? I know that this wasn't strictly safe as i essentially had a live supply with no cpc but i felt i needed to investigate this problem and i was as careful as can be.
Further testing on all the individual circuits from that board showed a few adding (around 8v) to the overall problem but i eventually traced the main culprits to the washing machine (40+v) and a dryer (15V). Is this normal? Obviously with all the earth lines connected this problem doesnt actually exist as any residual voltages would be 'drained' and would therefore be undetectable under normal circumstances so am i creating a problem where one doesnt actually exist? Currently my main concern is that the washing machine, being a cheap indesit, could be on its way out and would best be changed.
