Bosch GAL 12V-20 Charger supply Convert to 220v - Page 1
Forum section: electronics / repair

author: mentholflash
author_rank: Contributor
timestamp: February 21, 2025, 07:19:27 am
content: Hi allCan i convert this charger transformer to 220v.i bought a lot of tools from usa and i have four of these things.i bought a 110v to 220v transformer but can only plug 1 thing in at a time.i am not an Expert and will need slow explanationThanks in advancecheers

author: ME
author_rank: Frequent Contributor
timestamp: February 21, 2025, 08:55:16 am
content: Why not buy a generic power brick and swap the cable?,doubt theres any smarts in there?.

author: elektryk
author_rank: Regular Contributor
timestamp: February 21, 2025, 10:19:47 am
content: Does it have some components on the bottom?If charging controller is placed in the brick, then you cannot use generic one.

author: NE666
author_rank: Frequent Contributor
timestamp: February 21, 2025, 11:56:36 am
content: Quote from: mentholflash on February 21, 2025, 07:19:27 amIsn't that what power strips are for?Quote from: ME on February 21, 2025, 08:55:16 amIt's not a regular power brick, it's a lithium ion battery charger and the top-side holds a proprietary socket to take Bosch Pro 12v battery packs.

author: mentholflash
author_rank: Contributor
timestamp: February 21, 2025, 01:01:56 pm
content: Quote from: elektryk on February 21, 2025, 10:19:47 amthere are components on the bottom have included picIsn't that what power strips are for?it would have to be usa power strip then not sure what four of these of the one transformer would do to the transformer."It's not a regular power brick, it's a lithium ion battery charger and the top-side holds a proprietary socket to take Bosch Pro 12v battery packs".is there something specific about what looks like just something that powers a charging board in battery pack socket?cheers for replies

author: themadhippy
author_rank: Super Contributor
timestamp: February 21, 2025, 01:42:33 pm
content: I'd be tempted to try 2 in series

author: elektryk
author_rank: Regular Contributor
timestamp: February 21, 2025, 02:03:04 pm
content: Quote from: mentholflash on February 21, 2025, 01:01:56 pmSo there's a great chance that this is plain power supply. It doesn't even have optocoupler for feedback, but still current may be limited on primary side...Its also worth to check what's inside the part with battery connector, probably there will be some MCU/charging controller.BTW did you consider replacing charger as a whole?

author: reodor
author_rank: Contributor
timestamp: February 21, 2025, 02:10:09 pm
content: Quote from: themadhippy on February 21, 2025, 01:42:33 pmThat would only work if both chargers draw the same amount of current at all times.

author: tunk
author_rank: Super Contributor
timestamp: February 21, 2025, 02:20:20 pm
content: No expert, but I'm a bit surprised that there's no CE1 capacitor.

author: inse
author_rank: Super Contributor
timestamp: February 21, 2025, 05:19:22 pm
content: Maybe it has already been removed to make room for a 400V type 😁

author: inse
author_rank: Super Contributor
timestamp: February 21, 2025, 05:22:08 pm
content: Quote from: reodor on February 21, 2025, 02:10:09 pmI guess it’s because of his nickname 😆

author: mentholflash
author_rank: Contributor
timestamp: February 21, 2025, 06:22:56 pm
content: Quote from: inse on February 21, 2025, 05:19:22 pmYes not that easy to find 47uf 400/450v 16-18mm x 25mm max else the cover wont go back oncheers

author: inse
author_rank: Super Contributor
timestamp: February 21, 2025, 08:14:29 pm
content: No need to find another cap because you don’t need it.It won’t work, leave it as it was and run it from a step down transformer or get a cheap clone that works on 230V

author: mentholflash
author_rank: Contributor
timestamp: February 24, 2025, 07:53:46 am
content: Quote from: inse on February 21, 2025, 08:14:29 pmhi mateThanks for the response can you elaborate please?cheers

author: inse
author_rank: Super Contributor
timestamp: February 24, 2025, 10:16:58 am
content: I think it is most probably designed for 120V only, the switching transistor and transformer selected accordingly (the latter you can‘t even test).Swapping the capacitor was like trying to convert a Diesel car to Gasoline by changing the fuel tank.Worst case you will end up with a destroyed charger.If it was wide range capable, I don’t think they would have downgraded it.

author: inse
author_rank: Super Contributor
timestamp: February 27, 2025, 08:43:31 pm
content: Any updates on the conversion attempt?

author: mentholflash
author_rank: Contributor
timestamp: March 02, 2025, 11:48:34 am
content: I was told on here that the transistor was 5N50 is a 500V mosfet so would be fine.but i have more picsi am now looking for a transformer.And to repurchase 4 new chargers where i am is over $440Thanks for your help

author: tunk
author_rank: Super Contributor
timestamp: March 03, 2025, 12:01:36 am
content: No expert, but I got the impression that switch modetransformers are designed for each specific PSU. Soyou may have a problem getting the right transformer.You could try this:- use a 400/450V capacitor, plug into 120V and measurethe no-load voltage. Then plug it into 230V and againmeasure the voltage. If they're the same, it may work.(Or it may blow up.)- get one 230V charger, open it and see if they are thesame.

author: NE666
author_rank: Frequent Contributor
timestamp: March 03, 2025, 09:26:26 am
content: Quote from: mentholflash on March 02, 2025, 11:48:34 amYou're looking in the wrong places.https://www.ebay.com.au/itm/267169962791