Charging an electric gate battery

[troyak]

I have seen a number of posts about running 120v 15amps to a driveway gate, my question is a little different. I dont want 120volts, I just need 12v dc. What I would like to do is keep a 12v battery on a charger in my garage out of the elements and run 400’ of 16/2 low voltage wire to the gate. Would this work? Or could I keep the charger in my garage and run the same low voltage wire to the battery 400’ away?

I am aware of solar set ups, but I am quite far north, 54 degrees north, the days get pretty short in the winter.

Any expert advice would be greatly appreciated

 

[BrandonV]

You're going to have some crazy voltage drop at that distance with 16/2.

 

[The Cobbler]

online calculator shows a 2.5 voltage drop at 1 amp load using 14 g wire
at 8 g it showws .6 voltage drop

 

[troyak]

Damn, I was hoping that since it was a low voltage with a small draw it wouldn’t drop that much. I shall do more research. Thanks

 

[BrandonV]

Damn, I was hoping that since it was a low voltage with a small draw it wouldn’t drop that much. I shall do more research. Thanks

The problem is even if you put the battery out by the gate (which you pretty much have to) any trickle charger is going to just constantly think the battery is low... even if you used crazy thick wire.

As the voltage of the battery increases the voltage drop should get smaller as the charger will be putting less current into the battery over the 400ft but it's one of those things I think you should step back and say, "is this really worth it?".

 

[troyak]

Ok, I guess solar is really my only option

 

[theoldwizard1]

I don't want 120volts, I just need 12v dc. What I would like to do is keep a 12v battery on a charger in my garage out of the elements and run 400’ of 16/2 low voltage wire to the gate. Would this work?

The short answer is no !

Run 14/2 UF (can be direct buried) at 120VAC. You could use 16/2 if it is rated for 120VAC and can installed in a "wet" environment. Anything less than 14 AWG need to have an "appropriate" size fuse at the beginning of the run.

Yes, you will have substantially less than 120VAC at the end of the run, but you can buy 12VDC power supplies that will accept a "low" AC voltage input (I have seen some that will accept input voltage of less than 100VAC) ! You are only looking for a couple of amps worth of current at 12VDC so this should not be a problem.

Note, these are "power supplies", not battery chargers ! AC in, DC out. Yes, they usually can be adjusted up to 13-14VDC. End of discussion.

Running anything (like a power tool) that really needs 120VAC at the end of that run, will either blow the fuse at the head end or "let the magic smoke" out of that device.

TEWN wire (single conductor, either 16AWG or 18AWG) is rated for 600VAC and can be installed in a "wet" (underground conduit) location.

 

[troyak]

Ok, what about this?

500' UF UF-B 6/2 WG Cable Wire Direct Burial CU​

I am looking on Amazon. This is serious big 500 feet would weigh 150lbs. I suppose Ishould just bury this stuff deeper and run 120v to the gate.

Yes its getting up there in price, but I want to do things right, without busting the bank.

What do you guys think.

 

[BrandonV]

The short answer is no !

Run 14/2 UF (can be direct buried) at 120VAC. You could use 16/2 if it is rated for 120VAC and can installed in a "wet" environment. Anything less than 14 AWG need to have an "appropriate" size fuse at the beginning of the run.

Yes, you will have substantially less than 120VAC at the end of the run, but you can buy 12VDC power supplies that will accept a "low" AC voltage input (I have seen some that will accept input voltage of less than 100VAC) ! You are only looking for a couple of amps worth of current at 12VDC so this should not be a problem.

Now, these are "power supplies", not battery chargers !

Running anything (like a power tool) that really needs 120VAC at the end of that run, will either blow the fuse at the head end or "let the magic smoke" out of that device.

Out of curiosity for my own knowledge is there somewhere in the NEC that calls out the fuse?

Let's say the OP is using a 12V 1A battery tender. That pulls 15W or 0.125A.

Would you be okay installing a NEMA 5-15? What would a fuse look like on the other end (all I'm picturing is like an HVAC disconnect). Is there something made for this sort of application? Do you have to mark anything so people don't think you can pull 12A all day from it?

 

[tarmy]

I looked into this with my gate which was about 400’ from my shop. Ended up running some 6Ga. Out there with a separate 20A breaker. Works great and simply have two mid sized 12v batteries out there that the unit keeps charged to run the 24v gate opener.

 

[troyak]

Interesting, So I am not out to lunch on this. I dont have the gate or the opener yet, but I expect it to be 12 volts. But if I have power out there, i would add a couple low voltage lights as well, i wouldn’t be planning on running any power tools or stuff, that is what a generator is for

 

[troyak]

Thinking outside the box. Could you use a variable dc voltage power supply to deliver, say 14.4 volts to a 12v battery at this distance? This is if you were using say a 14/2 low voltage cable. You would measure the output at the far end and adjust it until you are happy, or am I out to lunch on this? I dont know enough about electricity resistance over a certain distance.

 

[u3b3rg33k]

I once did a 1000' run in the woods of 12/2. was for some christmas lights.

Voltage Drop Calculator

This free voltage drop calculator estimates the voltage drop of an electrical circuit based on the wire size, distance, and anticipated load current.

www.calculator.net

3 amps at 1kft, 120V, 12ga gets you 108V. works fine for christmas lights. or a slow charger (many switching supplies are rated 90-120v or 90-240v)

Don't overthink this. do what'll be cheap with off the shelf stuff. custom electronics is a terrible idea.

 

[troyak]

Thanks for this info. I certainly dont want to go overboard trying to get a solid line vice solar power to a gate

 

[cvairwerks]

Whole lot cheaper to do this instead:

Schumacher Electric 12-Volt Solar Battery Charger/Maintainer with Charge Control SP-1500 - The Home Depot

This 15-Watt solar battery charger is excellent for charging and maintaining 12-Volt lead-acid batteries. With extra-long cables, you can mount this unit in almost any place in your vehicle. Great for

www.homedepot.com

 

[troyak]

Yes, My default will always be solar, I am just looking for alternatives

I must say I love the interest I am getting with this forum. Just retired, so I have time on my hands to research this stuff, and will definitely be referring the the garage journal for my future projects.

Thanks to all

 

[vavet]

How self sufficient does this need to be?
I'd be inclined to go solar, knowing that in the winter, you might need to take the battery to the house to charge periodically.
If that's not acceptable, maybe you need more than 1 panel or maybe providing power to it directly is the right option.

 

[troyak]

I figured I would need a larger panel than what most gates would come with, but I also dont expect the gate to cycle more than a couple times a day on most days. I have thought about periodically removing the battery for giving it a good charge once a week, that wont be a problem, I will most likely go this route, but I am enjoying reading all these posts and getting ideas from those with a lot more experience with this stuff than I have.

 

[cvairwerks]

Troyak: We have a couple of crew cars at work that have either 5 or 10 watt solar tenders on them, as they don't drive enough to keep the batteries charged. One of the vans is a 7.3 diesel, and I don't think it's needed a jump start, even in the dead of winter, in something like 7 or 8 years.

 

[troyak]

I like that idea. In the winter add a battery tender to supplement the system, in the summer, I wouldn’t need it. Lots of sunshine here in the Summer and very long days

 

[cvairwerks]

If you throw the tender onto the gate battery as a permanent install, you probably would never have to pull the battery for a charge, only a changeout.

 

[dcg9381]

Ok, I guess solar is really my only option

Not that big of a deal. Just over-panel it substantially, maybe 200 watts and point it in the right direction. Big deal is that it's not shaded and has line-of-sight to the sun. If you can get 10-20A for 1-2 hours a day, you can make this work. The rest is about how many days you have with no sun at all (overcast) - and that's a function of storage/battery.

Make sure you get a charge controller that provides the 12V output on a "low voltage" protected circuit. That way you can't draw down the battery too far.

It's much simpler than it sounds..

 

[tarmy]

Interesting, So I am not out to lunch on this. I dont have the gate or the opener yet, but I expect it to be 12 volts. But if I have power out there, i would add a couple low voltage lights as well, i wouldn’t be planning on running any power tools or stuff, that is what a generator is for

Get the opener. My experience was that they are 24v…not 12v. Also, the weight and function (swing vs. sliding) will be important. They make many different motor sizes and if two swinging gates you may have two controllers.

My take is you are guessing at this point. They have all kinds of ways to power these things as well.

 

[justsam]

I don't claim to be a super tree hugger, but this is one application that solar just works well. If you still want to do other wise it would be good to know what size gate opener, how many operations per day, etc. A 24volt system would be better in terms of voltage drop if you are running DC out there. Really doesn't matter if you are running 120VAC. If you choose solar, and there is a chance it will not get battery charged, pick a unit that battery removal is easy to take out and charge. If there is a chance you will be adding lighting or cameras that could move you to the 120VAC however they too can be solar. Remember any apparatus you add at the site must deal with weather, potential theft or mischief.

 

[wyliesdiesels]

I have seen a number of posts about running 120v 15amps to a driveway gate, my question is a little different. I dont want 120volts, I just need 12v dc. What I would like to do is keep a 12v battery on a charger in my garage out of the elements and run 400’ of 16/2 low voltage wire to the gate. Would this work? Or could I keep the charger in my garage and run the same low voltage wire to the battery 400’ away?

I am aware of solar set ups, but I am quite far north, 54 degrees north, the days get pretty short in the winter.

Any expert advice would be greatly appreciated

400' of 16/2 will have way too much voltage drop

 

[wyliesdiesels]

Yes, My default will always be solar, I am just looking for alternatives

I must say I love the interest I am getting with this forum. Just retired, so I have time on my hands to research this stuff, and will definitely be referring the the garage journal for my future projects.

Thanks to all

solar will be cheaper than trenching pipe/wire or direct burial wire....

 

[theoldwizard1]

Whole lot cheaper to do this instead:

Schumacher Electric 12-Volt Solar Battery Charger/Maintainer with Charge Control SP-1500 - The Home Depot

This 15-Watt solar battery charger is excellent for charging and maintaining 12-Volt lead-acid batteries. With extra-long cables, you can mount this unit in almost any place in your vehicle. Great for

www.homedepot.com

2 - 6V golf cart batteries will give you enough power to run a 1,000W-2,000W inverter for 20-30 minutes. Plenty to run most power tools !

 

[walta]

I like wires. If it were me I would run a conduit and fill it 12 gage THHN conductors knowing you will see some voltage drop in the long wire. It looks like the “Battery Tender Plus” model is rated to operate down to 90 volts at less than 1/2 an Amp so low voltage should not be a concern for the charger just do not expect your power tools to work on that outlet.

Walta

 

[troyak]

Many more options, thank you, What ever I do, I will up date everyone, It may take some time, but I hate it when conversations just end without conclusion.

 

[gpiggaz]

Solar would be my recommendation even at that Latitude - Just up size the panel to get you more input power to the charge controller. You can buy cheap panels ( although shipping might be an issue) here: Santansolar.com They are mostly used panels, but there are some new ones available too.

 

[Innovate1]

I think solar is a good option but there are a couple ways to do wires without going crazy on the wire size.

You could do 240 V feed and a boost transformer to somewhere to raise the voltage to about 5 - 10% above nominal. That should be enough to run a trickle charger but not power tools.

Convert to DC at the feed end but feed something like 24 - 48V down the wires. Then used a DC input trickle charger at the other end. Several volts drop at the higher voltage isn't going to be an issue. I don't have any specific hardware suggestions for this. I did something similar but on a much smaller scale when I wanted to run some electronics that takes about an amp of power at the end of a Cat5 network run. 12V converter feeds the wires. 12V to 5V switching converter at the end. Switching converter reduces the current input by over 2x so input is about 1/2A. Works fine.

If you do long wires you need some good surge protection on the ends for electric storms.

 

[troyak]

Thanks for the option, but this is well above my electronics IQ. Perhaps sometime down the road I will want to go this route, just not now

 

[mm08822]

I would hardwire it from the house. Size it for a receptacle to run small hand tools unless you own a portable gen. All other solar ideas just add long-term complexity. Do it right from the beginning.......you'll only have to mess with it one time (and cry once!)

Running straight 240v out to it for a 240v battery tender is also an option......cuts down on wire size.

 

[troyak]

Sorry for the loooong delay getting back to my solution.

I went solar. The system came with a 10 Watt panel, and I added a 20 Watt panel to give me a total of 30. I have added the remootio smart opener to the system which allows me to see the voltage of the system at any time. It has never dropped below 12 volts. I don't use the gate very often, but I have 2, 1 watt bulbs on my gate, that run dusk to dawn, just to make it look fancy. And I had Christmas lights running off the system for about a month at Christmas, also using the dusk to dawn feature.

If anyone else is researching this, there is a low voltage option for many electris gates. It is an 18V Ac transformer, that you can run 1000 feet of low voltage 16 Gauge wire to the gate in order to charge the battery. I have Ghost Controls, but I know Mighty Mule also has this option, I assume others do as well. I have the transformer and wire incase I require it, but have not yet used them.

 

[dcg9381]

What battery are you using? I had to go up to a 50-100 watt panel as we were 3-7 days of overcast and the panel location was probably making power for 3-4 hours per day.

I'd also make sure my charge controller had 12V output with low voltage protect so you can't kill your battery.

 

[troyak]

I bought a 95 Amp/hour deep cycle battery from Costco.

The Ghost Controls instructions says it is limited to 30 watts of solar energy, so I have the two panels. 10 watt is pointing I am guessing around 50 degres from the horizon, the 20 watt is pointing around 20 degrees to catch the winter sun which only gets to 12 degrees above the horizon in December. I don't use the gate much, so it shouldn't need that much energy from the battery.

I have the battery and control sitting by my gate in a plastic box bought at Cabela's. On January 12th, 13th and 14th, the overnight lows were -45 degrees celsius. This is the codest temperatures I have ever seen, but the system kept working as it should. The battery charged during the day, and didn't freeze at night.

The Remootio smart opener and App is excellent, I am able to see the Device supply voltage at any time. I expected that I would have to put the battery on a charger every now and then, but never had to.