Darren asks this question, which is about a new caravan tested for its external loop impedance (Ze) - found to be too high. Regarding the Electrical Installation Condition Report (EICR), what to report? It has been answered by the ECA (Theme - Testing, Tools and Equipment):
This Q & A is one of thousands posted in our Technical Expertise area, and answered on a daily basis by our Voltimum Experts.
Question: I’ve been testing a caravan other day and found that when the Ze is tested at the caravan’s consumer unit – the result is a high 130 ohms. I then went out and tested at the hook up point, with the result that the Ze was again the same.
Now I am stuck to give certificate whether this electrical installation satisfactory or unsatisfactory.
It is a brand new caravan and inside, the installation is sound - and dead test result are all good, as is even the live test, and when I carry out the RCD test - all comply with the regulations.
The hook-up point has an RCD and inside the caravan also has an RCD. I noticed that the hook-up point has been supplied with two-core SWA cable, and armoured cable is used as the earth, which is why the Ze reading is so high.
Can you please advise me as to whether I should show the EICR as ‘satisfactory’ or ‘unsatisfactory’, and I will inform the caravan club that the earthing system needs to be upgraded, and I will put this in my test sheet as well. So, what should I do?
Answer: The first point to note is that you haven’t stated whether the earthing system is TT system or not – which is it?
Even so, 130 ohms is high and may not be stable, so you should inform your client to get the earthing system fully inspected and tested further.
To see many more Q & A in Voltimum UK's Experts Area, please click on the link. Experts from leading organisations provide online answers to your technical questions on a broad range of subjects. Our searchable database of existing Q & As now contains over 3,500 entries; you can browse through them here.