RCD x 5 touch voltage too high

[Farmelectrics]

yes it was some help thanks understand bit more my tester dosent detect touch voltage either but thanks for your advise

 

[JD6400]

25 v touch is for agricultural and i think construction sites , well it was for 16Th but not sure for 17Th now after malcolmsanford raised the question in the (switch heights on farms ) thread .
Malcolm , if you are reading this i will get back to you on this as soon as i have had a chance to check the current regs and gn3 !
As for your meter you can change this back to 25 V quite easily .
" Just " you say in your second post that your meter has just been calibrated , they probably finished calibrating it in 25 V mode and forgot to change it back before sending it out thats why you are now getting the odd readings .

 

[MarkieSparkie]

17th Ed of the Electrical Wiring Regulations standardised the touch voltage requirement at <50V in all cases. Under the 16th Ed there was a special touch voltage requirement of <25V for Construction Site Installations and Agricultural & Horticultural Premises.

 

[malcolmsanford]

17th Ed of the Electrical Wiring Regulations standardised the touch voltage requirement at <50V in all cases. Under the 16th Ed there was a special touch voltage requirement of <25V for Construction Site Installations and Agricultural & Horticultural Premises.

Thanks Mark that is what I thought. I don't have my 16th edition over here with me, but I had the thought that there were areas in the 16th that had 25volt touch requirements, but was unified to 50v in the 17th. I know that the new medical location was advocating the 25v touch voltage for certain zones, within the new amendment.

Thanks DP yes in that thread I saw that you mentioned the 25v in Agi and as I know you do a lit of Agi installs i was wondering if the 25v was a requirement from another set of standards. Cheers.

 

[Guest123]

16th Ed,

Reg 604-04-08, page 150, section 604 concerned Construction Sites and this was where the 25V came in.

Also 605-05-09 mentions the same rule for Agricultural & Horticultural premesis.

 

[Just]

Thanks all for the 25v explanation now how on earth do I change the thing back to greater than 50v for domestic!? Came up again yesterday on a x1 different property and won't complete the test. It's a DRC 430 RCD tester and as soon as I've got the cash it's going to be replaced! Worryingly there is nothing in the manual.

 

[XMB]

Looking at the instructions for the DRC 430 it says the test is stopped if the contact voltage rises above 25V so your meter is acting normally.

Although the BS7671:2008 regulations quotes 50V (although the amendment 1 now includes medical locations that do require 25V) I would be concerned if I did get a voltage above 25V as it means the earth is above 833R so in a normal environment it is indicating a problem (unless on a IT or TT supply).