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DC motor speed controller, too many inputs!

(crossposted)

Just bought a 36 V cordless drill, uses lithium ion batteries. Opened it up and discovered there are at least six wires coming from the battery pack to the motor speed controller.

Does that mean the speed controller is not going to work if I just connect 36V DC to the plus and minus terminals of the speed controller?

I suspect at least one of the terminals coming from the battery pack is to monitor the lithium-ion battery temperature (probably help keep it from exploding). I don't know what the others are for.

Maybe I'll have to buy a matching battery pack instead of using my own (36V, 3.5AH), or maybe I'll bypass the speed controller and go directly to the motor. But I'd rather use their speed controller even with its tiny heat sink.

Can't find DeWalt's amp hour rating for their 36V lithium-ion battery packs, lots of hype about the technology though.

Thank you.

Reply to
John Doe
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2716.5101 36VDC/20A 629321-00

r205

Reply to
John Doe

I loved your TV series, perhaps a movie is in the works?

[8~{} Uncle Monster
Reply to
unclemon

Is that one of your more useful replies?

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Reply to
John Doe

I was really upset when "John Doe" was canceled. It was one of the better shows on TV.

[8~{} Uncle Monster
Reply to
unclemon

It's not clear what (or why) you want to do. Why don't you want to use the battery pack that came with the drill? If you're looking for a backup battery, just get one like the one that came with the drill.

Mark

Reply to
redbelly

I could have been clearer about not having a battery pack for the DeWalt DC900 cordless drill. I bought the bare tool from eBay without a battery pack or charger.

I bought two different Panasonic drills so I could use some of their juicy 3.5 amp hour 12V batteries (4 total) for my project (with whatever cordless drill motor). Then I saw the 36V DeWalt (tool only) and thought that's perfect. Unfortunately it has a PWM with about eight inputs that probably must be satisfied somehow. So if I can't find the data for that PWM motor speed controller, looks like I will be selling one of the Panasonic drills and buying a battery/charger for the DeWalt motor. Or maybe I can find a suitable replacement PWM.

Yes, using a matching DeWalt battery (light but volatile lithium-ion) might be the way to go. Would be nice if DeWalt provided amp hour ratings for their batteries, but maybe their users aren't considered technically inclined enough to understand that.

Thanks.

Reply to
John Doe

I did some browsing around. Amazon.com lists a 2.4 A-hr spec on the Dewalt 36V battery:

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Pretty expensive suckers ($170 at amazon, and $100 for a charger), especially if you wanted to get a 2nd battery. Looks like this tool is meant for professional contractors.

Good luck,

Mark

Reply to
redbelly

...

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Great, I missed that, thanks.

There aren't any other standard use cordless drills at 36V either. I think the next biggest is a Milwaukee 28V right angle drill.

The DeWalt lithium-ion batteries and charger are not nearly that expensive on eBay. The way I see it, people buy the kits on sale wherever they can get them and then break up the kits. Apparently you can get stuff like batteries and chargers much cheaper (at certain times) than you would pay for the replacement charger or battery normally sold separately.

Reply to
John Doe

. . .

Yes there are, at least on this side of the pond:

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?cId=100372&ts=26691&id=24048

Don't know it it's avaialable in the US though.

--
John B
Reply to
John B

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