My electric fence has been installed and running flawlessly for at least 4 years. Recently the alarm went off and I checked the fence perimeter, all good. A strange thing is that the alarm clears when I remove mains and run the energizer on battery only. Today I took the energizer to Nemtek for testing and they found no fault with it. This is giving sleepless nights as it is a security risk. What could be causing this problem? 

On 2024/02/06 at 7:53 PM, Tim003 said:

My electric fence has been installed and running flawlessly for at least 4 years. Recently the alarm went off and I checked the fence perimeter, all good. A strange thing is that the alarm clears when I remove mains and run the energizer on battery only. Today I took the energizer to Nemtek for testing and they found no fault with it. This is giving sleepless nights as it is a security risk. What could be causing this problem? 

Did you manage to get any info regarding this?

I have exactly the same problem

On 2024/02/06 at 7:53 PM, Tim003 said:

My electric fence has been installed and running flawlessly for at least 4 years. Recently the alarm went off and I checked the fence perimeter, all good. A strange thing is that the alarm clears when I remove mains and run the energizer on battery only. Today I took the energizer to Nemtek for testing and they found no fault with it. This is giving sleepless nights as it is a security risk. What could be causing this problem? 

Can you please give details of which branch of Nemtek did you use for having it checked as I have clients that also need support/testing of their units on a regular basis. 

On 2024/09/09 at 6:29 PM, Willem die ratel said:

Did you manage to get any info regarding this?

Yes, there was a wire fault inside the conduit because it many wires (including the power cable) and the a live wire was damaged thus withing intermittently. The electric fence technician had to remove all wires from the energizer to the fence and reroute them to another point on the fence to avoid removing the pavement. 

14 hours ago, Scorp007 said:

Can you please give details of which branch of Nemtek did you use for having it checked as I have clients that also need support/testing of their units on a regular basis. 

 

I repaired my neighbour's Nemtek Wizzord recently.  I have also noticed that the 12V battery had been run down to 0V. After repair of the low voltage board, I  substituted the battery with a 12V bench psu and found when lowering this voltage that the unit 'cuts off' when voltage goes below 11V. This looks promising, except the microcontroller does not switch off and a current of 45mA is still being drawn. This of course depletes the battery over weeks or months,  and destroys the battery. Please take note of this when energizer is unattended for long periods of time. 

Also the mains charging voltage is 14.0V. Isnt this a bit high for a continuous float charge? 

Edited October 11, 20241 yr by BritishRacingGreen

On 2024/10/11 at 12:39 PM, BritishRacingGreen said:

I repaired my neighbour's Nemtek Wizzord recently.  I have also noticed that the 12V battery had been run down to 0V. After repair of the low voltage board, I  substituted the battery with a 12V bench psu and found when lowering this voltage that the unit 'cuts off' when voltage goes below 11V. This looks promising, except the microcontroller does not switch off and a current of 45mA is still being drawn. This of course depletes the battery over weeks or months,  and destroys the battery. Please take note of this when energizer is unattended for long periods of time. 

Also the mains charging voltage is 14.0V. Isnt this a bit high for a continuous float charge? 

@BritishRacingGreen I've got a Nemtek Druid 114 that just switches off by itself (blue screen) after about 30 mins, no errors, new battery and fence = 9 - Good. Any ideas why this would happen?

BTW, "Float" on these batteries can be 13.6V-14.4V with "bulk" charge sometimes going to 14.8V which is a little high. Nowadays though, all these batteries seem to last just into their 13th month.

9 hours ago, Brushless said:

@BritishRacingGreen I've got a Nemtek Druid 114 that just switches off by itself (blue screen) after about 30 mins, no errors, new battery and fence = 9 - Good. Any ideas why this would happen?

BTW, "Float" on these batteries can be 13.6V-14.4V with "bulk" charge sometimes going to 14.8V which is a little high. Nowadays though, all these batteries seem to last just into their 13th month.

If you disconnect the fence load, does it still disconnect? 

Also, when running from battery only, does that makes a difference? 

Some Nemteks gets very hot mainly due to the linear battery charging regulator requirement.  So I want to suggest that you check the temperature of the low voltage module's heatsink after 20 minutes or so. 

Edited November 19, 20241 yr by BritishRacingGreen

Thanks, it gives an error and switches off immediately without fence load. Haven't tried just on battery, will do so and will check heatsink temp too after a while.

On 2024/11/19 at 6:51 AM, BritishRacingGreen said:

If you disconnect the fence load, does it still disconnect? 

Also, when running from battery only, does that makes a difference? 

Some Nemteks gets very hot mainly due to the linear battery charging regulator requirement.  So I want to suggest that you check the temperature of the low voltage module's heatsink after 20 minutes or so. 

I've tested it now and it still switches off randomly, on battery or on mains. I've gone over it with a soldering iron for dry joints and have tried warming the entire unit up with a heatgun but it still trips randomly. Once during last night after running on mains for ~8 hrs and once again this morning after ~30 mins on battery, but there has been no pattern to when it turns off. Anything else I can try or look for?

On 2024/02/06 at 5:53 PM, Tim003 said:

My electric fence has been installed and running flawlessly for at least 4 years. Recently the alarm went off and I checked the fence perimeter, all good. A strange thing is that the alarm clears when I remove mains and run the energizer on battery only. Today I took the energizer to Nemtek for testing and they found no fault with it. This is giving sleepless nights as it is a security risk. What could be causing this problem? 

I seem to have same challenge. Energizer works perfectly on battery but alarm gies off when plugged in to the mains. The plug was short so I extended it without the earth cable. It's been working for about 4 years now until this day. At first I thought it was battery  problem but I replaced it but the problem persists.

Hi

I have had many electric fence problems since it was installed seven years ago.

For Joe King's problem, I am almost sure that all the earth connections to the earth spikes are not there or have been eroded. This is why I am almost sure that when he connects the mains earth, the fault presents itself. There is definitely a short to earth somewhere in the system. After a system has run for many years, the connecting HV wires crack due to the UV exposure, and sometimes it can be tricky to find.

Low or old batteries can be another problem. Low batteries can give intermittent faults, which can be very annoying.

My experience was that after several years, I found my fence light was very dull. I went to purchase another one and found that it did not work at all. I took it back and asked for it to be checked or replaced, which they could not and would not do. I went home and checked the fence again, only to find all the earths to the earth spikes were eroded away. After repairing them all, the lights were both good. I went back to the shop and apologised for putting up a fuss.

Insects and bird droppings are another annoyance. I clear these with a wet broom after switching off the system.