Low NE reading lighting circuit on an EICR

[Jim K..]

Did you mean to email Owain with that too?

[ARW]

Only posting to point out the point of testing and keeping proper records for additions to electrical circuits.

Today's first job was to sort the low ME reading.

A work colleague had already identified the cause as the "twinkly lights" above the bath (just to point out that these are lots of very small fibre optic lights in some boxing above a bath in a children's hospice) so permission and an agreed time to was needed to forcibly remove the side panels of the boxing in for further investigation.

And the cause was that the PSUs of the fibre optic lights were plugged into an RCD socket behind the boxing in. The RCD socket was the cause of the low NE reading.

The lights were fitted by volunteers a few years ago.

However then came my second job.

High Zs on drive lights (same place). Yep but only high because they were not designed correctly in the first place (and a pro designed that

11 years ago). The Zs reading of 1.8 ohms was lower than my guess of 20.0 to 2.5 ohms based on pacing out the length of the driveway.

Now the lights have been changed from sodium to LED and so rather than checking the tightness of every earth terminal (which IMHO would do nothing) I just swapped the MCB from a C type to a B type.

[Bill Wright]

Interesting.

Bill

[Andrew]

Couldn't the apprentice have measured the distance properly :-)