Results 1 to 8 of 8

Thread: lightning and earth leakages

  1. #1
    Full Member
    Join Date
    Jun 2011
    Location
    Midrand
    Posts
    33
    Thanks
    0
    Thanked 5 Times in 5 Posts

    lightning and earth leakages

    I notice this is becoming more common.

    Where when one has thunderstorms earth leakages trip. One then resets them, they go on first time but as soon as the lightning or thunder starts they trip again.

    I have normally found that replacing the units helps due to the fact that over years the earth leakages become sesitive to lightning and thunder. But lately that does not even help.

    One particular job in question:

    They have over head LV lines in the area that bring the power in to the plots.

    The earth leakages trip as stated above. I even went as far as to install two 3 phase earth leakages in the db that were connected on the supply side but had no conductors on the load side. This past weekend we had heavy thunder storms in JHB on Saturday and Sunday nights. Both those earth leakages were tripping.

    I want to check the Loop impedance to see if that is to high. If that is high I would assume this could be adding to my problem because I have a bad earth.

    Any other suggestions or thoughts?

    As I say this is becoming very common.

  2. #2
    Diamond Member AndyD's Avatar
    Join Date
    Jan 2010
    Location
    Cape Town
    Posts
    4,404
    Thanks
    513
    Thanked 854 Times in 687 Posts
    High earth impedence will cause slower tripping times. There are auto-restart earth leakages but I doubt they'd be less prone to tripping, it would just save them needing to be reset every time there'sa storm.

    Did you do an IR test on the installation, if there's a high standing leakage current that's close to the tripping threshold this might make it more prone to tripping during storms.
    _______________________________________________
    I am special and so is Vanash.
    _______________________________________________

  3. #3
    Suspended
    Join Date
    Oct 2007
    Posts
    2,346
    Thanks
    0
    Thanked 254 Times in 209 Posts
    i was called out to an earth leakage tripping...when i arrived everthing looking fine but the e/l unit would not stay up...i noticed a small hole the size of a pin head in the front of the unit...it was empty...when i opened the unit it had no metal components...they must have melted from a lightning strike and sprayed out the hole in the front of the unit...i can only asume this as i there was like a dust layer on the counter and floor in front of the unit...and i didnt see what happened.

  4. #4
    New Member
    Join Date
    Nov 2011
    Location
    Sandton
    Posts
    7
    Thanks
    0
    Thanked 0 Times in 0 Posts
    Hi greg. Trust all is well. I have been having the same problem at my place. It is getting so frustrating. Have you managed to find a solution ? I am not a electrician so its very hard to even figure out what's the cause. I have replaced the earth leakage with a new one with a overload and thought that would maybe assist(a private electrian said this will maybe work as the previous E/L was doing the same), but this has not at all worked. Any body have any ideas ?

  5. #5
    New Member
    Join Date
    Nov 2011
    Location
    sa
    Posts
    7
    Thanks
    0
    Thanked 0 Times in 0 Posts
    i have the same problem with a e/l with thunder storm i find that the cbi products have a problem i replace two of them and find the sensetivity on the products was very high i put the third one in problem solved

  6. #6
    Diamond Member AndyD's Avatar
    Join Date
    Jan 2010
    Location
    Cape Town
    Posts
    4,404
    Thanks
    513
    Thanked 854 Times in 687 Posts
    You could try installing surge arrestors if there aren't any already there. They should be installed in lightning prone areas anyway.
    _______________________________________________
    I am special and so is Vanash.
    _______________________________________________

  7. #7
    New Member
    Join Date
    Nov 2011
    Location
    Sandton
    Posts
    7
    Thanks
    0
    Thanked 0 Times in 0 Posts
    Thanks AndyD for the suggestion. I have no idea what a surge arrestor looks like so I i'm not sure if its there already.
    Its just very odd that the E/L are so sensitive. Even if the lightning if far away the E/L trips. As well in this case if its like heavy thunder its doing the same thing. To be honest I think I really need a Honest, reliable, professional Electrician who knows what his doing to sort this board of mine out. Unfortunately a electrician with these qualities are hard to come by these days.

  8. #8
    Diamond Member AndyD's Avatar
    Join Date
    Jan 2010
    Location
    Cape Town
    Posts
    4,404
    Thanks
    513
    Thanked 854 Times in 687 Posts
    Quote Originally Posted by Yogs View Post
    I think I really need a Honest, reliable, professional Electrician who knows what his doing to sort this board of mine out.
    That was going to be my next suggestion. I would test the DB and earthing arrangement before you go any further.
    _______________________________________________
    I am special and so is Vanash.
    _______________________________________________

Similar Threads

  1. [Question] electrical earth continuity
    By Groen Karoo in forum Electrical Contracting Industry Forum
    Replies: 5
    Last Post: 14-Sep-11, 08:07 PM
  2. Lightning arrester testing
    By Dave A in forum Electrical Contracting Industry Forum
    Replies: 7
    Last Post: 01-Oct-10, 07:47 PM
  3. CBI earth leakage units
    By murdock in forum Electrical Contracting Industry Forum
    Replies: 2
    Last Post: 29-Oct-09, 12:44 PM
  4. Earth hour
    By Dave A in forum General Chat Forum
    Replies: 38
    Last Post: 04-Apr-09, 11:38 AM
  5. Google Earth
    By Faan in forum General Business Forum
    Replies: 0
    Last Post: 30-Jul-08, 08:52 PM

Did you like this article? Share it with your favourite social network.

Did you like this article? Share it with your favourite social network.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •