Ext. Cord for Charging-Max Length???

[konakid]

I would like to charge my cart away from the house. I was thinking of using one of those long 100-150 ft. heavy gauge construction cords. The kind you can run a Skill Saw off of.

What kind of feedback can you give me on the best way to get electric from a standard outlet the maximum distance for charging purposes. I have a 72 volt AC cart - if that is a consideration. (Not sure of the charger wattage - but is that the main consideration?)

[jdunmyer]

You should be able to use a heavy-duty cord as you describe with no problem. The charger probably draws less current than a Skil saw. Of course, you can look at the charger's nameplate to be sure.

[konakid]

I did find some specs hidden in the cart's manual.

It said to use a dedicated 15 amp circuit and then I could go 100ft. with 10/3 AWG (3 wire 10 gauge).

Does anyone know if there are 8 gauge 120 volt ext. cords - and how much further I could go with that if I can find it? And do you think 15 amps is really necessary? Are they just asking for overkill to be cautious?

[cgtech]

It will draw over 10a for an extended period when charging "fully empty" batteries. I made my own extension cord from bulk wire (designed for exposed use), and ends i sourced at the local big box home improvement warehouse. That way you can use any size you need, custom fit to the length you need.

[gravelydude]

Kona,

There are no 8 gauge extension cords readily available on the market. If you need to go more than 100 feet, you should consider installing a receptacle at the intended charging area, and running some UF (underground feeder wire), which is similar to romex, to your main panel. This would be your best solution. Making up an extension cord longer than 100' will result in some voltage drop occurring between your power source and the charger. If you do not feel comfortable doing this project yourself, ask an electrician to give you a bid on the job. It may not be as expensive as you think.

Jack

[jdunmyer]

Kona,
Look at the nameplate on your charger to see the current draw. Then, figure out the distance you need to run from your nearest power outlet. Next, go to the Web and find a voltage drop calculator that's based on wire size. If you allow 3% drop, you will need heavy cable, indeed; if you allow 10%, much lighter wire is acceptable. Personally, I wouldn't worry about 10% drop for a battery charger, as it doesn't present the extreme surge load like a motor.

Think about this: how much distance is there between the service panel and the "nearest outlet"? Most outlets are wired with #12 wire, and it could easily be 50 feet or more between the 2.

That said, if you need to run 100 feet of wire, would it not be possible to simply park closer to the outlet?

[konakid]

Thanks for the feedback guys. I think I have enough info to figure out the numbers myself. Unfortunately I just don't know that much about electrical "stuff." But now I know how to go about doing the math.

Incidentally, my situation is terribly restrictive. Going underground is impossibly expensive. I am on lava rock. And to to make it worse, it is solid jungle/forest - so even if I wanted to go underground, I would need to clear the forest first - in order to get the heavy equipment in necessary to break up the rock.

So, I have an area that I already cleared, and have a large canopy installed to keep things out of the rain. And I just measured - it is 150 ft from a receptacle on my main power pole with a 25 amp breaker.

I can lay some outdoor wire on the ground - really the only choice. It is pretty much inaccessible to human traffic, and I could unplug it when not in use - and if grounded and only 120v, I think I can live with it. Fire is really not an issue either - usually very wet around here.