Results 1 to 10 of 10

Thread: Electric Fence Triggers Siren When Raining

  1. #1
    Junior Member
    Join Date
    Feb 2019
    Location
    Germiston
    Posts
    17
    Thanks
    21
    Thanked 4 Times in 3 Posts

    Electric Fence Triggers Siren When Raining

    Afternoon All

    Our 6 year old fence recently started to trigger the alarm during rainfalls. Inspection of the fence reveals nothing: no debris, nothing arcing.

    After a few hours of dry weather, fence works perfectly.

    Any suggestions of where or what to check?

    Thank you.

  2. #2
    Diamond Member
    Join Date
    Apr 2010
    Location
    planet earth
    Posts
    3,943
    Thanks
    153
    Thanked 317 Times in 287 Posts
    This seems to be a common problem ... my neighbours fence is the same ... as it starts raining you hear the electric fence alarm ... you reset the alarm and it works no problem ...even while it is pouring down with rain ... as soon it its starts raining again the alarm is activated.

    There have been 3 electric fence companies try fix it ... without any joy.
    Comments are based on opinion...not always facts....that's why people use an alias.

  3. Thanks given for this post:

    Annetta (14-Jan-22)

  4. #3
    Gold Member
    Join Date
    Jun 2017
    Location
    Port Elizabeth
    Posts
    723
    Thanks
    19
    Thanked 186 Times in 156 Posts
    Quote Originally Posted by Annetta View Post
    Afternoon All

    Our 6 year old fence recently started to trigger the alarm during rainfalls. Inspection of the fence reveals nothing: no debris, nothing arcing.

    After a few hours of dry weather, fence works perfectly.

    Any suggestions of where or what to check?

    Thank you.
    It is generally dust on the insulators or a hairline crack that the water sits in and tracks str to earth .Difficult to see as it does not " jump " across a gap and create the spark

    See if you can get it down to a zone and clean insulators

  5. Thanks given for this post:

    Annetta (14-Jan-22)

  6. #4
    Silver Member
    Join Date
    Jul 2008
    Location
    Germiston, South Africa
    Posts
    381
    Thanks
    21
    Thanked 46 Times in 42 Posts
    My gutshot reaction would be a cracked insulator.

    Sent from my SM-A705FN using Tapatalk
    To make a mistake is human, to learn from that mistake is knowledge and knowledge is strength.

  7. Thanks given for this post:

    Annetta (18-Jan-22)

  8. #5
    Diamond Member
    Join Date
    Apr 2010
    Location
    planet earth
    Posts
    3,943
    Thanks
    153
    Thanked 317 Times in 287 Posts
    I want to see if the person who is going to test and issue the COC for the electric fence picks up the fault.

    I have a feeling the fence next door has a problem with the cable between the unit and the fence.

    My thoughts ... after a couple dry days ... if you take a hose pipe and spray water into the pipe and each row fence insulators ... where ever the insulator is cracked it should activate the alarm ?

    IF an insulators is cracked ... why doesnt it activate while it is raining ... would you detect leakage voltage on the steel fence ?
    Comments are based on opinion...not always facts....that's why people use an alias.

  9. #6
    Silver Member
    Join Date
    Jul 2008
    Location
    Germiston, South Africa
    Posts
    381
    Thanks
    21
    Thanked 46 Times in 42 Posts
    In fact the cracked insulator should trigger an alarm, especially if your energizer settings are still configured with their default settings.
    Typically the Energizer will trigger the alarm after the return voltage has been reduced below a preset level after a preset time, which is normally 3 seconds or 3 pulses.
    A triggered alarm is normally caused buy a high voltage fence cable touching an earthing point for longer than it takes to trigger the alarm.
    If the cracked insulator is filled with water and the resistance is so low that on each pulse the voltage drops below the set level (3kv?), then the alarm will sound.


    Sent from my SM-A705FN using Tapatalk
    To make a mistake is human, to learn from that mistake is knowledge and knowledge is strength.

  10. Thanks given for this post:

    Annetta (18-Jan-22)

  11. #7
    Silver Member
    Join Date
    Jul 2008
    Location
    Germiston, South Africa
    Posts
    381
    Thanks
    21
    Thanked 46 Times in 42 Posts
    Quote Originally Posted by ians View Post
    I want to see if the person who is going to test and issue the COC for the electric fence picks up the fault.

    I have a feeling the fence next door has a problem with the cable between the unit and the fence.

    My thoughts ... after a couple dry days ... if you take a hose pipe and spray water into the pipe and each row fence insulators ... where ever the insulator is cracked it should activate the alarm ?

    IF an insulators is cracked ... why doesnt it activate while it is raining ... would you detect leakage voltage on the steel fence ?
    I'm thinking that dirty water in the cracked insulator may offer a lower resistance? Once the pure rainwater has replaced it, the resistance is raised and the voltage no longer drops below the threshold. Just a thought

    Sent from my SM-A705FN using Tapatalk
    To make a mistake is human, to learn from that mistake is knowledge and knowledge is strength.

  12. #8
    Junior Member
    Join Date
    Feb 2019
    Location
    Germiston
    Posts
    17
    Thanks
    21
    Thanked 4 Times in 3 Posts
    We checked and found two cracked insulators.
    We had a particularly harsh hail storm a few weeks back and our West fence took the brunt. We also replaced the energizer.

    We have had a good downpour since all of the above was done so we hope this has resolved the issue.

    Thank you all for your inputs.

  13. Thank given for this post:

    Derlyn (18-Jan-22), Dylboy (18-Jan-22)

  14. #9
    Silver Member
    Join Date
    Jun 2020
    Location
    Fourways
    Posts
    250
    Thanks
    63
    Thanked 11 Times in 11 Posts
    Intresting thread!

    Could an IR test be done of sorts to prove if there is a short of sorts ? I mean a fence is massive volts so it may not be enough but still curious.

    Connect one end to the line and the other to the earth wire or wires and then test?

    Sent from my SM-N960F using Tapatalk

  15. #10
    Gold Member Derlyn's Avatar
    Join Date
    Mar 2019
    Location
    East london
    Posts
    829
    Thanks
    53
    Thanked 86 Times in 80 Posts
    Quote Originally Posted by Leecatt View Post
    I'm thinking that dirty water in the cracked insulator may offer a lower resistance? Once the pure rainwater has replaced it, the resistance is raised and the voltage no longer drops below the threshold. Just a thought

    Sent from my SM-A705FN using Tapatalk
    @ leecat. I've been following this thread and I think you have hit the nail on it's head concerning the resistivity of rain water. Your point of dirty water as a result of the dust mixing with rainwater and decreasing it's resistivity is spot on. The same happens with municipal water as a result of the chemicals added.

    There was a thread regarding instant showers tripping the ELR with Municipal water but working perfectly with harvested rain water.
    It can be seen here ... https://www.theforumsa.co.za/forums/...er+resistivity

    This has been an interesting and thought provoking post.
    Thanks Annetta.

    Peace out ... Derek.

Similar Threads

  1. Electric fence COC
    By ians in forum Electrical Contracting Industry Forum
    Replies: 0
    Last Post: 13-Dec-21, 09:27 PM
  2. [Question] Neighbors' Electric Fence Bleeding into my fence
    By willemma in forum Electrical Contracting Industry Forum
    Replies: 5
    Last Post: 10-May-21, 07:37 PM
  3. [Question] Electric fence COC
    By SKPK in forum General Regulatory Compliance Forum
    Replies: 1
    Last Post: 21-Apr-17, 11:27 AM
  4. Electric Fence Specs
    By daveob in forum General Chat Forum
    Replies: 27
    Last Post: 11-Jun-12, 03:33 PM
  5. Do your electric fence maintenance now!!!
    By garthu in forum Technology Forum
    Replies: 9
    Last Post: 14-Oct-10, 10:38 AM

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
  •