# WiFi Switch for Solar Fence

#### JRVA875

Joined Aug 21, 2020
5
Thanks in advance for the help. I think this is just a stupid question, but I’ve never fooled with switches and I have no electrical experience so I’m confused on what I need.

I have a farm with a high tensile electric fence powered by a solar setup I built with this energizer:
https://cyclopsfence.com/collection...s-brute-8-joule-12v-battery-powered-energizer

There’s also a car battery and solar panel there.

It works great but, I spend a lot of time walking back and forth to turn it on/off when I’m trying to repair the fence. The energizer is within WiFi range of my house (120ft or so) so I’d like to add a WiFi switch and hopefully be able to turn the fence on/off with my phone from wherever. I found some DC WiFi switch on Amazon, but I’m not confident that they can handle the task I need them for. Can someone please point me in the right direction?

#### Dodgydave

Joined Jun 22, 2012
10,063
Post a link to the switch you have in mind, as long as it can handle the current rating it should be good.

#### MisterBill2

Joined Jan 23, 2018
9,503
If that is a problem then the fence is not at all right! A well built electric fence needs repairing once in the spring and then only after damaging storms. So if it needs frequent repairs the fence is the problem. UNless you have water buffalo damaging it. Or Elephants.

#### crutschow

Joined Mar 14, 2008
27,941
One problem with the Amazon units is that they often don't spec how much current they use from the battery.

#### schmitt trigger

Joined Jul 12, 2010
469
Indeed;
Even if the device itself can’t handle the current, a secondary heavy duty relay can provide the required capacity.
Do you have neighbors which could generate WiFi interference?
As you mention, 120 ft in open range should be within WiFi’s capabilities, as long as there is no interference.

#### ErnieM

Joined Apr 24, 2011
8,183
Since this is a remote solar installation that switch is a bit tricky. I would recommend a latching relay that doesn't need power to stay on or off. This unit from Amazon may work but I did not study it too hard, seems not to be a latching type relay.

Meaning the relay draws current, about 30 mA, when it is on,

I once worked on a very small electric fence on top of a lighthouse, also solar powered. We used a hard mechanical switch to disable it. While it ran off solar the cell and battery were part of the controller. The guys before me switched the high voltage out to make it safe when people were about, When I replaced this I opened the unit and switched the 6 or 12 volt power itself by adding some wire and a cable gland at the unit bottom. Much safer as neither the switch nor the wire previously used were rated to withstand that voltage

#### MisterBill2

Joined Jan 23, 2018
9,503
Indeed;
Even if the device itself can’t handle the current, a secondary heavy duty relay can provide the required capacity.
Do you have neighbors which could generate WiFi interference?
As you mention, 120 ft in open range should be within WiFi’s capabilities, as long as there is no interference.
The suggested Heavy Duty Relay would probably draw more current than the fence charger, and so the battery would need to be recharged a lot more. That might be beyond the ability of the solar charging system, so the protection would end before dawn. That may be a worse problem, depending on what sort of creatures your system is keeping out of the garden.
The fact is that when you are repairing the fence you are close to it means that switching it off and on from 120 yards away makes very little sense if the charger is close to the fence. And if the charger is not mains powered, why would it not be located at the fence? I see a different issue here, since it is quite a challenge to work on a fence from 120 yards away.

#### JRVA875

Joined Aug 21, 2020
5
If that is a problem then the fence is not at all right! A well built electric fence needs repairing once in the spring and then only after damaging storms. So if it needs frequent repairs the fence is the problem. UNless you have water buffalo damaging it. Or Elephants.
You're right. I tried to just make the explanation simple. Everyone understands the need to repair a fence. I more frequently need to touch the fence because I practice rotational grazing and therefore move my animals to a new paddock every 1-2 days. However, I only have a perimeter fence around 70 acres and I construct each paddock with temporary electric netting, which I connect to the perimeter fence in order to energize it. Hopefully repairing the fence is a very rare thing.

#### JRVA875

Joined Aug 21, 2020
5
Indeed;
Even if the device itself can’t handle the current, a secondary heavy duty relay can provide the required capacity.
Do you have neighbors which could generate WiFi interference?
As you mention, 120 ft in open range should be within WiFi’s capabilities, as long as there is no interference.
My closest neighbor is 1/2 mile away so I'm good on interference

#### JRVA875

Joined Aug 21, 2020
5
This is the unit that I was considering:
https://www.amazon.com/dp/B07F6YZXST/ref=cm_sw_r_tw_dp_x_IzbrFbBAXWWHY

Since the fence (4 strand, high tensile) is around 70 acres, I could realistically be 1/2 mile or so away from the energizer when I want to be able to touch it and not get shocked. Ideally, I always remember to turn it on/off when I'm near it, but it'd be really nice to be able to do it remotely when needed.

#### MisterBill2

Joined Jan 23, 2018
9,503
At my Uncle's farm. for the electric fence that they used to keep a bull in his place and not with the cows, they had a red plastic insulated handle with a hook, so they could open the fence. They explained that it was a far more shocking charger than for the cows, and since I had seen it sparking to grass and burning the grass I could believe it.
My point being that there are devices to let you open the fence without switching off the charger.
It should also be possible to make a similar hook device from a foot-long piece of plastic water pipe, either black poly or the white hard plastic, and some #9 steel wire. Much cheaper and more reliable than switching of the charger with a wifi thing.
Do you have access to the terminals of the battery that gets charged by the solar cells? There are other remote control options besides wifi.

#### MisterBill2

Joined Jan 23, 2018
9,503

#### gerty

Joined Aug 30, 2007
1,302
I have used one of these on 2 different occasions with excellent results. Might be a little overkill, but I've tested the range at 3/4 mile with several obstacles in between. You also get a beep, audible feedback that the signal was received..

Joined Jan 15, 2015
6,136
I would start with something like this. Most of these smart devices work with a pretty wide range of software applications on any smart phone. Most also work with for example Amazon Alexa, "Alexa turn on the fence, Alexa turn off the fence".

Something to beware of is the little Songle relays on these boards seldom meet their specifications so consider slaving an automotive relay to the board. Then you can easily switch 12 VDC 30 ~ 40 Amps.

On a similar note I have been experimenting with a few of these units for switching 120 VAC mains power. I bought 4 Teckin SP 10 smart sockets for $20 USD or about$5 each. The app for my smart phone was free and they work through my home WiFi network. Most smart switches work with a wide range of apps which is nice.

Another option for the distance involved is a simple remote relay card but you would need to carry the key fob transmitter.

Ron

#### MisterBill2

Joined Jan 23, 2018
9,503
You will probably want some sort of indicator to tell you that the fence charger is OFF, since grabbing a live electric fence would tend to be rather exciting. Not at all fun, but certainly exciting.

#### ErnieM

Joined Apr 24, 2011
8,183
I use one of these Sonoff switches in my house, together with Alexa.

I can use my phone's Alexa app to control the light when not connected to any WiFi, so as long as your phone has bars and the fence has Wi-Fi you can control the fence.

Same with the eWeLink Sonoff uses. That has the bonus of displaying the switch state to confirm it is off.

Joined Jan 15, 2015
6,136
Same with the eWeLink Sonoff uses. That has the bonus of displaying the switch state to confirm it is off.
Mine does the same in either my Alexa or Smart app, then too, I guess if not already there a LED pilot light could easily be added to the fence charger.

Ron

#### ErnieM

Joined Apr 24, 2011
8,183
A pilot light local to the fence charger switch is not the most useful thing when by definition you are not there and using a remote controller.