Difficult battery charger task

The OP can't do the project as he described it safely. He just doesn't know what he's doing.

But since he's going to try it anyway, Mr Stirling gave some very good advice. The OP should carefully follow all the precautions and good advice in Mr. Stirling's list.

If I could, I would add at least a pair of real polycarbonate safety goggles which are ANSI Z87.1 compliant, and a pair of rubber insulating gloves. He should go to an electrical supply house for these rather than buy the cheapie imports from the "do-it-yourself-poorly" mega hardware store down the street. For the most part, the megastores sell wannabe toys, manufacturing culls and QC rejects for safety equipment.

A good pair of goggles and insulating gloves will reduce the chance of eye damage or electrical burns, but only if they're used.

Chris

Much better. All you need now is a 3 ohm, 43,200 watt resistor bank. That's not as difficult or as expensive as it might seem (although it will cost quite a bit)..

Try calling Surplus Sales of Nebraska. They've got tons of wirewound power resistors, and will help you design the least expensive load bank for your application. Remember to use the correct mounting hardware, manufacture a frame with sufficient air space between resistors to avoid hotboxing, and remember generous use of forced air (the 20" box fans they sell for $15.00 USD each at the hardware store are really good for this).

Use a remote voltmeter to determine the correct point to disconnect the load bank, and you're good to go.

Mr. Stirling's advice is still valid for switching and releasing the load bank. And please remember the rubber gloves and safety goggles.

Good luck Chris

Yes they do. Bodies smelling of charring are particularly offensive to the olfactory system ;-)

...Jim Thompson

The poster is from Turkey- may be that mustached belligerent female Larkin was hitting on a few months back.

Much better. All you need now is a 3 ohm, 43,200 watt resistor bank. That's not as difficult or as expensive as it might seem (although it will cost quite a bit)..

Maybe a bank of water heater elements, it will make enough hot water for several showers; nice to go to the hospital clean, the morgue doesn't care though. Tom

| > Run the leads of the batteries (divided into 30V or so groups) outside | > the cover. | >

| > Connect several adequately rated knife switches mechanically together, | > and use these to isolate the batteries, so they are at a safe potential. | > Make sure you can visually see that all the knife switches are disconnected | > before approaching. | > NEVER go anywhere near the battery pack with any metal buttons/tools/ | > eyeglasses/rings. | > Wire the groups of cells up seperately, and case them seperately. | | The OP can't do the project as he described it safely. He just doesn't | know what he's doing. | | But since he's going to try it anyway, Mr Stirling gave some very good | advice. The OP should carefully follow all the precautions and good | advice in Mr. Stirling's list. | | If I could, I would add at least a pair of real polycarbonate safety | goggles which are ANSI Z87.1 compliant, and a pair of rubber insulating | gloves. He should go to an electrical supply house for these rather | than buy the cheapie imports from the "do-it-yourself-poorly" mega | hardware store down the street. For the most part, the megastores sell | wannabe toys, manufacturing culls and QC rejects for safety equipment. | | A good pair of goggles and insulating gloves will reduce the chance of | eye damage or electrical burns, but only if they're used. | | Chris |

Ditto to the above and would add a buddy system. All parties should have first aid with CPR. Never work on this kind of device alone.

Don't forget the eye wash station and neutralization solutions for spills ...

Is hydrogen buildup going to be a problem?

Fire fighting systems? Structure? Are you going to locate your battery room behind the washroom? Floor loads? Fusible links in the heating, ventilation and air conditioning plenums. Is this thing going to be safe?

Add a couple dozen more items in a 24-7 backup system for replacement of defective cells.

The OP is clearly over his head. It might be to his credit to walk away rather than bungle the job.

BTW anybody know how to limit the discharge current to 120 Amps ;)

Dan

On Mon, 27 Jun 2005 06:03:17 -0700, boothmultipler wrote: ...

By making a sane decision as to what load you connect your battery pack to.

Good Luck! Rich

LOL!

Thanks! Rich

How about, "BMF Resistor"?

Cheez! Rich

Yes, for the third fraqgging time, CONNECT IT TO AN APPROPRIATE LOAD! I once worked for a guy who had a 1000-amp dummy load in his attic. I don't know what happened to the load; he sold his company to these guys:

Good Luck, Rich

But, do they annotate whether your underpants were clean at the TOD?

Thanks, Rich

Oh, christ, then it's nothing. Go to Beale AFB, California, and ask the SR-71 blackbird techs how they do it.

Or are you filling in for them now? ?:-/

Good Luck! Rich

Right. Maybe he could get that Toko--- (whatever the name is) guy to do it. Solves two problems at the same time.

They're very hard to find now-a-days. You would need PFM to get your hands on one. Tom

Sheeesh! Political-correctness has come to circuit design.

BMF stands for "Big Mutha F....er" ;-)

...Jim Thompson

No! No! No! BMF is a VALUE, NOT a part name ;-)

You can have BMF caps, resistors, transistors, heat sinks, etc.

...Jim Thompson

"...ing". It's an adjective. ;-P