The other side of the module seems to have a 2-wire connection to the battery – is this a proprietary format for talking to the BMS in some lithium packs? Almost certainly serial if it is – and possibly gets passed through the module to the other port. Might be worth looking at lithium BMS datasheets?

Don't see any mention of RS232 in that page – do the other ads specify it thus? At that price, perhaps the easiest way to find out is to buy one.

Neil – are you asking how RS232 works or are you wondering about the format of the control data you need to send to this thing? I rather suspect the latter. I expect the format is semi-proprietary but isn't going to be a well-guarded secret. The vendors might tell you (in Chinglish!) if you ask.

Dunno if you can find any trace of these devices publicly but these are what you find when you rip open a Lenovo L-Ion pack.

If you ask the seller they will probably link you to a data sheet.

I'm loosely reminded of emailing a chinese seller after buying a part of him. He miss understood and replied sorry we will get it right next time we makes some. Maybe the serial interface doesn't work.

If you google the entire listing title a number of links come up. Some are video's. Might be some info there.

John

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I think the only way you get any detailed info is to reverse engineer the schematic. I have used quite a few modules similar to the one you show. The descriptions often have errors and you dont know what you get until it arrives!

On this one it mentions non synchronous rectification but nowhere does it say AC input or what AC frequency.

Not relevant to your bench PSU purpose but some people have assumed that the CV/CC modes meant that it can be used to charge Lithium type batteries, they can do, but they are not really optimised.

The modules I use are mostly DC:DC buck or buck-boost. 10A versions are not much more expensive, some have meters but if not there are plenty of cheap digital V and A modules and since they are not on the regulator board are easier to put where you want on your front panel.

By totem poled do you mean transformer secondaries in series? also what current do you consider high for a bench PSU?

Ian P

Duplicate post removed

Edited By Ian Phillips on 06/02/2016 20:38:15

Neil,

The module in this video looks familiar:

**LINK**

MichaelG.