Making a Bench Top Power Supply From a 24 Volt 5 Amp Battery Charger

[XJohnDoe001x]

Friends, do anyone have a schematic for making a Signet HB 150 24T battery charger that came from a Pronto Sure step power chair into a variable volt, variable amp bench top power supply? Or can someone give me some ideas on how to proceed and some features that I may want to consider.

 

[NMNeil]

I'm far from an electronics expert, very far in fact, but I'm old and have been around the block a few times, so I give the following advice honed from decades of experience in such projects.
Sell it and buy a bench top power supply.
It will work properly, have a warranty, end up being cheaper and it significantly reduces the risk of electrocution and other annoying side effects of such projects when 'modifying' high voltage/amperage devices, and yes, I have the scars to prove it

 

[(*steve*)]

If it was a dumb battery charger then you could add a regulation stage to it to make a power supply.

However, this is a multi-stage charger which will change its behaviour over time to bring a battery safely up to full charge and then (presumably) maintain it. As such it's not suitable to be converted (easily) to a power supply. You might be in the middle of using it when it decides the "battery" is charged and turns off.

 

[dave9]

Yeah there are too many variables here on how it senses and terminates charge to know if it's viable.

However while we're on this topic I recently came across a new buck regulator design (meaning PCB layout) that was *new to me* in the realm of cheap *junk* coming from China. Most of the cheap adjustable regulator boards have glaring flaws against implementing into an enclosure chassis without more parts and more modification.

It doesn't regulate current but the form factor and aligned front facing POT and display make it easier to drop into any chassis with enough front space for it:

https://www.ebay.com/itm/DC-DC-5-36...ck-Step-Down-Power-Supply-Module/202261622042

 

[BobK]

You might be able to pull it apart and use the raw voltage output, eliminating the charger logic. Depends I guess on how modular the design is. If it is fully inyegrated, this might not be simple.

Bob

 

[kellys_eye]

Better off starting with an old laptop or printer PSU. I have a few 36V 3A (might be 2A) power packs from old printers - laptop PSUs with around 20V output are very common.

 

[XJohnDoe001x]

Thanx Bobk,