Odd Size 25x70mm 63V 10000uF Blown capacitor in PowMr Solver Inverter - Page 1
Forum section: electronics / repair

author: pkomoro
author_rank: Newbie
timestamp: October 22, 2024, 03:46:20 am
content: I have a PowMr solar inverter that suddenly started smoking on me. I purchased it on eBay directly from the factory store but they are ignoring my requests for any warranty service, so it looks like I'll have to tackle the repair myself. (Fair warning for anyone else contemplating buying something from a Chinese company and expecting any warranty repairs)The issue seems to be that at least one of 4 capacitors on the 48VDC output output blew. I'm having no luck finding a capacitor that will fit. I've checked all the usual places (eBay, Amazon, Digikey, Mouser, AliExpress).Capacitor is 63V 10000uF in a 25mm x 70mm size. Any suggestions of where else to look?The nearest capacitor that I found with a 25mm diameter is a 63V 6800uF 25x50mm "audio electrolytic capacitor". Does anyone have any advice on using this a substitute? I haven't desoldered the 4 capacitors yet so I'm not sure if it's just 1 bad one (that's my current best guess), but if it's just 1 bad cap then I'm guessing it should work well enough?

author: johansen
author_rank: Super Contributor
timestamp: October 22, 2024, 11:33:25 pm
content: what is the power rating of this inverter?if its the 5kw unit for 600$, how much load was on it?I would double or triple the capacitance, read the data sheet and add up the rms amp rating of the capacitors. you need around 50 amps rms if its a single phase pwm inverter.

author: pkomoro
author_rank: Newbie
timestamp: October 22, 2024, 11:51:01 pm
content: The inverter is the POW-HVM6.2M-48V-NIt's a 6200W 220/230/240V single phase inverter. I attached a picture of the label to this post.At the time failure, it was running an electric water heater, which normally uses around 4000-4500W. I think I had it set at 220V or 230V output.I smelled smoke, so I ran into the solar system room and the inverter was spewing smoke from the fan but was still running and producing power. I had to manually shut it off with the switch on the side.It's been running well in this setup for around 6 months. In the summer it ran my whole-house AC, and at night time I would switch off the AC breaker and put on the water heater.The capacitor that failed is on the 48V battery side of the circuit, not on the output side. Battery voltage was probably right around 50-52V, so if the heater was taking 5000W, that would have been around 100A of current but, again, this was very typical use in my case, so it looks like random component failure.

author: johansen
author_rank: Super Contributor
timestamp: October 23, 2024, 03:54:16 am
content: so it depends how the topology is setup.if the solar mppt bucks the panels down to 50 volts and sends it to the battery, then another inverter section takes the 50 volts and turns it into 240vac, those capacitors have to handle the combined rms sum of the ripple currents from both converters.

author: indeterminate
author_rank: Regular Contributor
timestamp: October 23, 2024, 11:52:17 am
content: The caps are not really 10000uf 63v low ESR hi ripple current components that's why they blow up frequently.you are lucky that they did not catch fire as many of them contain flammable electrolyte.after you repair this the next thing to go will be all the fets & there gate drives.the cap you listed earlier is unsuitableyou are looking for 4700uf 63v low ESR high ripple current components from a reputable supplier & manufacturer , everything on ali is fake rubbish.

author: pkomoro
author_rank: Newbie
timestamp: October 23, 2024, 03:25:24 pm
content: The issue I'm having is that I can't find any supplier that has 25mm diameter 63V 10,000uF caps.Everything in the 10k uF range is 30mm or 35mm, and I don't think that I'll have space to fit those. The caps on the board are fairly tight together, with perhaps 1-2mm space between them. I ordered some 30mm 10,000 uF caps to see if they will fit. If it's just one cap that blew and the remaining 3 test OK then I might be able to squeeze one 30mm into that area if I'm lucky, but I doubt that I could get two 30mm caps to fit next to each other.You're thinking stepping down to 4700uf will be adequate? Digikey has these that are 25mm x 52mm low ESR, but going from 10,000uF to 4700uF seams like a huge drop.https://www.digikey.com/en/products/detail/chemi-con/EKMH630VSN472MQ50S/4000677