Drill charger broken

[AbdulW87]

Hello all,
I need some advice about fixing my drill charger. I have a challenge xtreme 18V cordless drill. The charger is broken, after checking it with a multimeter, I have narrowed it down to a blown transformer. The ratings on top of the charger body show transformer output voltage at 18 v and current at 2A.
My question is can I use an laptop charger with an 18v 2A output and connect it to the charger circuit.
Thanks.

 

[Mark A]

Is there no warranty left on it? These cheap tools usually have pretty long warranties if you can find the receipt.

 

[Kennysevenfold]

why bother, the drill is like £30 brand new?

 

[AbdulW87]

@mark no, no warranty left I am afraid.

@Kenny drills are cheap especially with so many offers right now, but I like to imagine anything can be repaired , so giving it a try. At this point I am having trouble with the input wattage specified on the charger case. If that doesn't play a big part then the fix should work.

 

[touch]

Wattage (power) is related to voltage and current (power = voltage x current). If both power supplies output the same voltage and current then they'll have the same power.

 

[bitslice]

My question is can I use an laptop charger with an 18v 2A output and connect it to the charger circuit.

Yes, but caveats.

be careful of leaving it charging for too long, the original charger may have been charging at a reduced or variable rate and may automatically go into a float mode. And it may not have been charging at exactly 18v, probably more like 16.8v

So yes, you can ram 2A@18v into a battery and it will charge,
stick it on a cheap timer plug so you don't forget about it.


See post #7 and #8

 

[K.C. Leblanc]

Yes, but caveats.

be careful of leaving it charging for too long, the original charger may have been charging at a reduced or variable rate and may automatically go into a float mode. And it may not have been charging at exactly 18v, probably more like 16.8v

So yes, you can ram 2A@18v into a battery and it will charge,
stick it on a cheap timer plug so you don't forget about it.

I've has a quick google and it seems that some Challenge Xreme chargers used an external PSU not that different from a laptop charger.

There's even one here;

http://www.ebay.co.uk/itm/18V-AC-DC...ammer-Drill-/191749209014?hash=item2ca524bbb6

 

[bitslice]

Ah, that's running at 23v
Thanks for that, I couldn't be bothered to google

so 18 batteries @1.25v each = 22.5v

so just charging at 18v DC isn't going to fully charge them



but look on ebay for a 24v DC adapter, they are much more common and about £3
an extra volt won't damage anything

 

[Deleted member 66701]

Get a hobby charger - you'll be able to charge anything with it.

Don't forget the power supply to run it.

http://www.hobbyking.co.uk/hobbykin...O6_50W_5A_Balancer_Charger_w_accessories.html

Ah, that's running at 23v
Thanks for that, I couldn't be bothered to google

so 18 batteries @1.25v each = 22.5v

so just charging at 18v DC isn't going to fully charge them



but look on ebay for a 24v DC adapter, they are much more common and about £3
an extra volt won't damage anything

There are 15 cells in an 18v nicad pack (I assume you have a nicad pack and not nimh or lion) and nicad cells are charged to 1.45v (1.55v if performing a forming charge) so that's 21.75v total pack voltage fresh off the charger. A nicad pack will soon lose voltage though and the resting (nominal voltage) for a fully charged pack is 18v or 1.2v per cell. You can't just attach a power supply (23v or otherwise) straight to the battery pack as you need to use the right charging algorithm that terminates the charge when the pack is full.

 

[bitslice]

You can't just attach a power supply (23v or otherwise) straight to the battery pack as you need to use the right charging algorithm that terminates the charge when the pack is full.

You can (as I mentioned in post #6) use a timer.
it just won't be as efficient.

I think we are clearly talking about bodging this, not spending lots of money

I've always gone with ni-cads being around 1.25v ?