Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Suggested Answer
  • Locked Locked
  • Replies 9 replies
  • Helpful Answers 1 Helpful answer
  • Subscribers 38 subscribers
  • Views 1002 views
  • Users 0 members are here
Options
You may also be interested in
This discussion is locked.
You cannot post a reply to this discussion. If you have a question start a new discussion

portable battery pack to test caravan rcd's

aligarjon

Hi guys.   A friend of mine is setting up a business servicing caravans.  He is plugging into the mains to do some testing and his rcd tests are obviously taking out the house rcd.  I know there are battery packs available to keep the power on for electronic devices/routers etc if we have to turn the power off for customers working from home.  I don't have one myself.  Would these sort of things be suitable for testing an rcd on a portable caravan or any caravan for that matter ?

Thanks

Gary

  • 0

    Well for testing from any supply that is already connected to an RCD you could cheat and use the incoming L & N only and not the installation E.

    That is for say in this instance plug in your caravan to say a test socket you have made up with the L as L and both the N from the N and the E from the N. In effect you are creating a "TNC-S" supply for the test rig.

    Hope that helps

  • 0

    I think there are portable battery driven inverters - in theory they should work, but you might have to be careful to get one with a proper sine wave output (which usually means more expensive).

    Wouldn't it be simpler just to do the RCD tests with the Earth lead of the instrument connected to the supply N rather than PE?

       - Andy.

  • 0

    Or use an isolating transformer............

  • 0

    Cheers guys.   I will pass it on and let him do some  research.

    To be fair he did mention an isolating transformer.

    Gary

  • 0 in reply to aligarjon

    Well mentioning it is half the battle. Wiring it with a secondary side NE bond is the most important thing - then it is not really an isolating transformer in the normal (IT) sense more of  fault current breaker. But to test RCDs he would only need a few hundred watts as the duty cycle will be minimal - not need for some great arm stretching lump.

    Just using L and N is Ok, but do a supply polarity test 1st. Not all caravan leads preserve  LN sequence, and the idea of faking the CPC from the L instead of the N does not bear thinking about.

    Mike.

  • 0

    Do an Up and down RCD test. Most RCD testers will do a 2 wire test. One probe on the incoming neutral and the other probe on the outgoing line. Press the button and record the readings. No need to worry about tripping the upstream RCD. Simples.

  • 0 in reply to John Peckham

    Yes, there is a discussion on this in this thread from within the past couple of years; https://engx.theiet.org/f/wiring-and-regulations/23034/caravan-rcd-trip-power-connections

    The discussion includes some illustrations of the method - including a method of carrying out the test on caravans (or PRCD adaptors or similar) without having to access IP2X terminals.

  • 0 in reply to John Peckham

    Thanks John

  • 0 in reply to gkenyon

    Thank you very much Graham. That is very useful.

    Gary

Join us to get the best from IET EngX.

Joining EngX lets you personalise your experience so you stay up to date on the topics that interest you, plus you’ll be able to make connections who are looking to collaborate, exchange ideas and more.

Join us Not now

Community Rules & Guidelines