32 volt Battery Tender?

[SKYCHENEY]

Mike,
Check this link out. It claims you can put 110 in and get 220 out or vise versa. I think this is the same type we have.

http://www.sterling-power.com/htm/ist.htm

[Beckytek]

Yes Mike, Sky is correct. On my boat I can use the 120 volt cable in and run the 240 volt stuff. I overloaded the system and blew the 30 amp fuse but as long as you don't overload it. it works. With the battery charger you wouldn 't be drawing that much current to worry about. Sorry I didn't think of that sooner.

[MikeP]

You mean I can attach a single 120VAC shorepower cable to the boat from a conventional 120VAC socket w/adapter and produce 240 on the boat? Sounds like magic! But it's certainly an easy solution (except that I don't own any 30A 120V) cables..until later today!

I was also interested in the "Charge 'em/shut everything off and leave 'em" solution. I'm just concerned that over the 5-6 month period that the boat will be out of the water this time would let the batteries self-discharge enough to freeze the electolyte and destroy them over the winter. I know this is not a problem if the batteries are kept charged...

[Trojan]

MikeP
What is going to run them down if every thing is turned off. The only way that happens is if the battery is bad to begin with. Ether way you win. It will weeds out the bad one.




BILL

[MikeP]

Lead/acid Batteries in good condition self discharge on their own at around 4-5% per month even if not connected to anything. So 5 months is a fair bit of discharge but whether it's enough to matter, I don't know. Probably not since it is considered OK to discharge them to the 50% level for normal operations. Also, it's obvious your experience shows it's not a problem. There will be at least two critical months, Jan/Feb where the temps could be in the high teens/low 20's for a week or two. That's what I'm most concerned about.

[Trojan]

MikeP the transformer doesn't know which way it is hooked up. BUT, the amperage will be reduced alot. Of course you know that you need to rewire the transformer for the opposite direction use. You also must check to see if is a step up, step down type transformer. Some are just a one to one isolation and won't work. They use one to one because they are cheaper to make. Make sure it will do what you want first. It should show the wiring on the transformer case and the amperage. Its going to cost ya about $ 250. bucks or more to convert to this. With cables and plugs. It just depends on how fancy you want to get just to keep your batteries at charge. Then you need to be there to plug it in. I think it would be cheaper to buy a small step up transformer just for your charger. Temporary hard wire it to your panel or charger and use an extension cord. Small amperage transformers are not to costly.



BILL

[Trojan]

Mike I live in south east Michigan. My boat is stored right on the shore of Lake Erie. It gets real cold there for 4 months and I have never had a problem. But that doesn't mean there can't be. Its just the way I do it. I'm not about to drag those PITA 8Ds out of the boat to take home. Nor am I going to uncover the boat climb a ladder with 10 inches of snow at 20 below just to check the battery charge. Its a warm weather boat. I'm to old for that crap. Gives me chills just thinking about it.


BILL

[SKYCHENEY]

Mike,
No conversion should be necessary. Hatt wired this to do this job. You just have to flip the breakers in the stbd engine room to accomodate the 30amp 120v input. And as far as the costs of cables and plugs go, at least you will have them for later use if you ever get to a marina with only 120v service.

[Trojan]

How does Hatteras rewire a transformer with breakers? Or do they just by-pass the transformer with a separate circuit. How does that work? If he doesnt have an isolation transformer. He can just get a matching female plug and only wire the circuit half that has the charger on it with 110 volts..

BILL

[SKYCHENEY]

How does Hatteras rewire a transformer with breakers? Or do they just by-pass the transformer with a separate circuit. How does that work? If he doesnt have an isolation transformer. He can just get a matching female plug and only wire the circuit half that has the charger on it with 110 volts..

BILL

I don't know, Bill. But as Beckytec stated, it does work. You can run the 240v stuff with the 120v input. I'm not an electrical engineer, nor have I even looked at the schematic, but if you flip the breakers, you can run it that way. Maybe it's a special transformer of some kind. I don't know. My boat has two Jefferson Electric Isolation transformers. I don't know anymore than that.