Erbauer 18-24v battery charger

[Cornboats]

Does anyone know how to get hold of an electrical schematic for this battery charger? I have Ryobi portable drills but the charger is missing so was wondering if I could use an Erbauer charger which I do have instead. The battery connections can be altered on the charger but the Ryobi batteries are charged through a temperature detector on the negative line. The Erbauer charger has a 3rd terminal but its positive.

[sam_sam_sam]

Re: Erbauer 18-24v battery charger

Are you using ni-cad batteries or are you using Li-ion batteries
It makes a big difference which batteries we are talking about

It might be a big maybe ?

[sam_sam_sam]

Re: Erbauer 18-24v battery charger

The Erbauer charger has a 3rd terminal but its positive.

You need to know how this 3rd terminal is being used for me to answer your question

[Cornboats]

Re: Erbauer 18-24v battery charger

Thanks for taking the trouble to reply. They're Ni-cad batteries. I don't know how the 3rd terminal works, I thought getting hold of a schematic would help me understand. On the Ryobi charger the negative went through the 3rd terminal via a temperature fuse to the negative of the batteries.

On the Erbauer when powered on I get 26v across + & - and 26v across the 3rd terminal and - , so I've assumed the 3rd terminal is +.

I've got 2 Erbauer chargers, 1 has an ac transformer the other has no transformer but instead a massive capacitor 45micro farrad x 450v.
Here's some pics of both.

[sam_sam_sam]

Re: Erbauer 18-24v battery charger

Do you have a battery for this charger if you do can you take the battery case off of it and see how it is wired

[Cornboats]

Re: Erbauer 18-24v battery charger

No I'm afraid I don't. I stripped the Ryobi down which is how I know that charging is thro the 3rd terminal.
I keep searching the net in the hope I'll find a schematic. Can you reverse engineer the circuits in the photos I posted?

[sam_sam_sam]

Re: Erbauer 18-24v battery charger

Not really this why you need a battery for this charger because it can be a few different ways it can be done one way is just use a thermo switch or a resistor type sensor or “k” type or something similar

[sam_sam_sam]

Re: Erbauer 18-24v battery charger

There some ni-cad chargers out that very easy to use and work fairly well

https://www.ebay.com/itm/Ni-MH-Ni-Cd...53.m1438.l2649

One note on this charger you should replace the capacitors in this charger they unknown brands

[Cornboats]

Re: Erbauer 18-24v battery charger

I looked at the link. Charge rate is 1 amp compared to Erbauer of 2.8amp. I'm not going to resort to buying a replacement just yet, not when I have perfectly good robust chargers- just not configured correctly. I shall perserver a bit longer and endevour to find a wiring diagram.
Appreciate your help.