Gate Power with 1700 Foot Driveway

[Besoeker]

Battery power gate controller (in case power goes out) with a trickle charger. Run a #8 to the gate in the conduit previously installed. Maybe run a light or two also at the gate...

See post #7.

 

[kwired]

I echo the first part. I'd look at a 13.8VDC operator with a local deep cycle battery. You can run one conductor out & have the charger at the house. Put a diode at the battery. Use a ground return.

"Wait!" you say.... "Voltage Drop..."

But that implies current.

Working backwards... End-state; the battery is fully charged and draws no current from the charger. Before then, yes there is drop, but you're putting some coulombs into the battery. Patience, Grasshopper.

You do need a way to up the charge voltage to make up for the fixed diode drop.

Now, iffen I were building it, I might use a 48V->13.8v converter, or even just a series regulator at the battery.

As for capacitor storage.....I've not looked at such in years and yield to gar.

Makes sense. Charge voltage must be higher than battery voltage to make charging current flow. If you have a deep discharge that is when charging current will be higher, but it could be limited by drop over the distance, but again it will just take more time. It is not like you will be standing there waiting for it to charge.

 

[Besoeker]

With 2 AL and a 10 amp load at 240 VAC I come up with less than 5% drop and I doubt the load would be that high. Place a small transformer to get the 120 volts and it's done.

We can think it to death or just get out an do it. Honestly 1700' is not that far, consider the parking lot lighting at your local shopping plaza.

I don't disagree with your solution although 2 Al seems like quite a big conductor.
How much would 3400 feet of that cost compared to a small battery charger and battery?

 

[stickboy1375]

I see these gates done all the time, and they just stick a meter behind a bush...

 

[kwired]

I don't disagree with your solution although 2 Al seems like quite a big conductor.
How much would 3400 feet of that cost compared to a small battery charger and battery?

You would need an equipment grounding conductor also.

2-2-4 URD is about 1.25 per foot. I don't have price for 2-2-2 which really is what should probably be run since upsizing ungrounded for voltage drop the EGC would likely need to be #2 also.

Based on 2-2-4 price that is about $2125.00 for conductors alone plus you still need to bury it. If in area where subject to rodent activity it is highly recommended to put it in a raceway.

I would opt for battery and solar charger myself - even knowing batteries will need replaced every 3 or 4 years minimum if there wasn't anything else needing power that couldn't be run from the batteries anyway.

 

[mike_kilroy]

I echo the first part. I'd look at a 13.8VDC operator with a local deep cycle battery. You can run one conductor out & have the charger at the house. Put a diode at the battery. Use a ground return.

Have you ever tried to use ground for a conductor at 12vdc? It is none existent. Even 50vdc or 75vdc... infinity.... you need ac to get a low resistance ground - it has to do with chemistry and the ac changing field that makes the connection from the ground rod to earth..... very interesting topic. easy to prove at home with a 12vdc battery, 12v ite bulb, and 12vac power source.

I assume a drive 1700' is similar to ours in that the 7200v from the street is taken to a 7200->240 xfmr within 200' of the house, so to just add a meter behind a bush includes installation of a step down xfmr from power company and a min monthly bill that around here is around $ 50 so really not an option.

 

[iwire]

I don't disagree with your solution although 2 Al seems like quite a big conductor.
How much would 3400 feet of that cost compared to a small battery charger and battery?

2 is not a big conductor, in AL it would not be that costly. It would cost more then charger and a battery at installation but I think the on going maintenance issues with a battery would be at best a pain in the rear and at worst costly.

I am a huge fan of keeping things simple, especially for a dwelling unit.

 

[hillbilly1]

2 is not a big conductor, in AL it would not be that costly. It would cost more then charger and a battery at installation but I think the on going maintenance issues with a battery would be at best a pain in the rear and at worst costly.

I am a huge fan of keeping things simple, especially for a dwelling unit.

Ahhhh! The KISS philosophy! How I miss those days! You just about have to have an engineering degree to open a live panel anymore!

 

[Besoeker]

2 is not a big conductor, in AL it would not be that costly. It would cost more then charger and a battery at installation but I think the on going maintenance issues with a battery would be at best a pain in the rear and at worst costly.

I am a huge fan of keeping things simple, especially for a dwelling unit.

The KISS principle? I'm all for that.

We do a fair bit of work in supplying UPS systems mostly in the 10kVA to 400kVA range.
In truth, we don't make any of the parts. We just do the system design and integration.
Mostly, the batteries are Yuasa VLRA (valve regulated lead acid) 10 year life.
They are maintenance free. The electrolyte is gel so doesn't spill even if the case gets damaged.
I looked into that in some detail when trying to get permission to air-freight a consignment.*
On that basis, I'm inclined to think that battery maintenance is not a big issue.


*From the manufacturer's data sheet:

Special Provision A67, contained in IATA Dangerous Goods Regulations and the ICAO publication, Technical Instructions for the Safe Transport of Goods by Air and states that:

"Non-spillable batteries are not subject to these Instructions if, at temperature of 55C, the electrolyte will not flow from a ruptured or cracked case and there is no free liquid to flow and if, when packaged for transport, the terminals are protected from short circuit."