MeanWell SP-320-48 Repair Thread

[amberwolf]

I have been pulled away from this for quite a long time now, and at some point misplaced the box the whole project was in. I have now run across that box a few days ago, and then today I also ran across 3 really cheap S-150-48 MeanWells at Goodwill, on 50%-off day, basically two bucks each. I hooked the cord off the needs-repair 350W MW to one of them, and it appears to work, at 48.3V output. I didn't put a load on it yet, and haven't tested the others. No idea what they had been used for before I got them (but am curious). The stocker at GW said there were 6 of them that morning; he doesn't remember if the other 3 were the same as these.

No further info yet, but if I'm lucky I'll run into some time to finish this repair soon. Ish. I hope.

 

[dnmun]

wow, whatta deal.

it is really easy to get to the adjusting trimpot and add in some more resistance in parallel or in series where that trimpot is so that you can really extend the voltage range on the output.

AREALDEAL!

 

[amberwolf]

I actually would like to figure out a way to parallel them (without using big diodes on each one's output, in case of slight voltage variations on each one), to get 9A max, and then just series them with the current-controlled 55V Sorenson that can do 9A in it's sleep. Then use the Sorenson to do the current limiting and the voltage adjustment, on whatever I am charging (since practically any pack I want to use on the bike will be at least a few volts higher than it's max voltage)

That assumes these are (or can be made to be) isolated units, whcih I don't know. I cant' find them in the product lists on the MW site.

I thought I had seen a thread on paralleling MWs a while back, but I cant' find now, and don't recall if the conclusion was yay or nay or if there even WAS a conclusion.

I found Auraslip's thread on these exact same units from last year, something like "how hard can you push a meanwell", but that wasnt' it. A few other MW threads, none of which had what I was after.

 

[Kingfish]

I tried to parallel mine back in spring of 2010 but determined on that summers' road trip it was for naught with How-To: Meanwell 63-84V CV/CC Charger - however I believe NeilP has written at length on the subject with his thread converting meanwell power suply into Lipo charger.

FWIW, I gave up on the S- & SP series, and sold them off. Presently I am on this path: Review: Meanwell HRP-600 Series, although the next ebike I build will likely use the RSP-2000 series which is designed for up to 4 units in parallel. The RSP is a good series, though be warned that the 2400 and 3000 flavors use 180-264VAC for input, as well as being quite a bit more expensive.

That said, AW - I cannot argue with your thrift, and if you can make it work then I tip my hat in your general direction Maestro 8)

~KF

 

[amberwolf]

I suppose I will have to just try it. I have rather large diodes avaialble from old linear power supplies, so if I must I can use those to keep them from feeding back into each other, and I can use multiturn pots to replace the singleturn pots for votlage adjustment to make them more closely matched.

I briefly had an idea tha tI could use op-amps from each one to compare it's output to the actual total output of the set, and have that autoadjust it's otuput up or down to match, but this would still require some sort of resistance or something to cause a voltage difference between each PSU and it's connection to the pack. Otherwise they will all have the same voltage at the outputs, but not be actually outputting that voltage.

If they have somewhere internal that could be used to reference the actual output voltage from, that might make this workable, but I am not really sure how I could make the circuit so taht it doesn't just keep constantly changing the voltages o each PSU and not end up at the correct one.

A program on an MCU could be used to do this, but that's startng to get pretty complex for what is supposed to be a quick-and-dirty-and-cheap charging method.

 

[day-nightsigns]

Did anyone ever finish working on or repairing this issue? Looks like it just dropped off.
I have the same issue with the 5 and 12 volt ps. Need some help, anyone....anyone. 8)