Poles for the Dewalt 24 v Battery?

[boilermanc]

Hi all, I have several 24 volt dewalt batteries and few drills that work with them but the batteries are dead. I successfully "bumped" several 14 and 12 volt dewalts back to life so want to try it with the 24's before I pitch them. I do not know the poles on the batteries though. There are 4 connections on those batteries.

I have done the google search but nothing that I can find. Anyone know or can check theirs for me?

thanks in advance!

 

[Fcvapor05]

You should be able to figure out which is which within a few minutes with a multimeter..

 

[AA/FC]

I tried to "bump" one of those back to life once....I killed it permanently. Not sure what went wrong. That was a few years ago now and I've since bought all new 18V Milwaukee Fuel tools to replace those old Dewalts that I had.

Let us know if you have any luck with it.

 

[boilermanc]

You should be able to figure out which is which within a few minutes with a multimeter..

Hey thanks. The batteries are dead. I put the multimeter on 200m and I can get just a 1 to show up as I run across the 4 blades. So I guess the question is here, I dont know that I know what to test when the battery is dead?

 

[uart]

Hey thanks. The batteries are dead. I put the multimeter on 200m and I can get just a 1 to show up as I run across the 4 blades. So I guess the question is here, I don't know that I know what to test when the battery is dead?

Hopefully that was the 200mV range boilermanc. If so then 1mV is very dead indeed.

Without having one to look at I can only guess, but there's two possibilities that I think are likely.

Possibility 1.
With most Nicad stuff any extra battery terminals are normally only used by the charger, not by the tool itself. So if you look carefully at where the battery contacts to the tool, you may find that only two of those four contacts are used. Those would the two main poles.

Possibility 2.
If all 4 contacts really do connect to the tool then it's possible that DeWalt have decided to split the 24 volt pack into two banks of 12 volts each. There are some definite advantages in doing this.

To see if this is the case, can you try measuring the voltage between pins 1 and 2, also between pins 2 and 3, and finally between pins 3 and 4 of the pack (just number the pins left to right for reference). Make sure you use a voltage range on your multimeter.

BTW. Can you try the charge the battery even a little bit before testing? Or does the charger just totally reject it and refuse to do anything at all?

 

[G_P]

These are NICAD right? If its lithium do not "bump" them or they will probably explode.

I would open the packs up and examine the cells. Very good chance there is a dead cell in there. It will be easy to spot as it will likely be leaking out one end and there will be dried crystals all over that end.

 

[boilermanc]

Hopefully that was the 200mV range boilermanc. If so then 1mV is very dead indeed.

Without having one to look at I can only guess, but there's two possibilities that I think are likely.

Possibility 1.
With most Nicad stuff any extra battery terminals are normally only used by the charger, not by the tool itself. So if you look carefully at where the battery contacts to the tool, you may find that only two of those four contacts are used. Those would the two main poles.

Possibility 2.
If all 4 contacts really do connect to the tool then it's possible that DeWalt have decided to split the 24 volt pack into two banks of 12 volts each. There are some definite advantages in doing this.

To see if this is the case, can you try measuring the voltage between pins 1 and 2, also between pins 2 and 3, and finally between pins 3 and 4 of the pack (just number the pins left to right for reference). Make sure you use a voltage range on your multimeter.

BTW. Can you try the charge the battery even a little bit before testing? Or does the charger just totally reject it and refuse to do anything at all?

Brilliant Uart! I checked the drill and it only have two contacts so that made it pretty easy to figure out which ones were the right ones to work with. I did my little "tap tap tap" with a good battery and one of the 24v are charging as I write! I will try it on the other two when I can and hopefully gets my drills up and running. Hate to replace them or the batteries, there expensive!

thanks!