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AIMS Power 1250w Inverter Charger not working, blown 300a fuse

HighTechLab

AKA Dexter - CTO of Current Connected, LLC
Joined
Sep 23, 2019
Messages
1,635
Not necessarily looking for help, more sharing my great Friday-morning before coffee experience. Maybe there is something to be learned, maybe since I haven't had my coffee I'm missing everything. Also when dealing with Aims, I plan to share my experience working with them.

I have a 1250w inverter/charger from AIMS Power that I've been using for some time with a BigBattery 170ah owl. The use case is as a UPS for my desk, which is two computers, printers, and other small doo-dads. Max load is probably around 600w, but the rest of the time around 200-300w. I like this inverter because it has an IEC input connector (the same type of connector things like computer power supplies use) and then a GFI output. Literally all I had to do was connect up the Anderson connector from the battery to the inverter, plug a few cables in, and then we were good to go.

It should give me about 3-4 hours of backup power in case I am doing some work in a panel and need to shut the power off for an extended period of time. We are off-grid, so our power goes out from time to time for this kind of thing and I dislike how these cheap UPS units you get from amazon/bestbuy only last like 5 minutes.

Our main power source is a Sol-Ark 12k. Last night I was up til about 1AM on the computer, then went to bed, leaving (of course) 20 tabs open, all sorts of programs without totally saving, the usual when you get over-confident that stuff isn't going to shut down. Everything was working and I went to bed.

This morning, I roll out of bed about 8:30, and start heading over to the office, and Jarrett (my partner) is trying to figure out why everything is off. The inverter was totally off, BigBattery voltage meter was not on...Same kind of behavior as when the battery gets run dead.

So I tried connecting up a regulated power supply to the inverter, inverter wouldn't turn on with 12.00v input...So we crank up the voltage to 14.00v, still nothing. At this point, I realized that if the BigBattery was fully discharged, then the voltage wouldn't have just gone up this easy, and at this point it was obvious to me that something totally failed. We pull out the BigBattery pack and check the 300a fuse inside...Blown.

Obvious to me now, it seemed that the inverter had failed...So we pull it out of the rack, take it to the autopsy table and take it apart. I'm thinking that inside I'm going to find burned fets, maybe a stuck transfer switch, something crazy like that.

But inside, it was as spotless as the day I got it. How do you blow a 300a fuse without causing serious damage I ask myself.

I was tempted to take it down to nothing and find the problem, but Jarrett wants us to check into the warranty first before we potentially void that. This unit was like $450, so it'd be nice to have a working solution again.
 
i'm glad y'all ok and that only a little of the magic smoke got out.

do you mind me asking type of fuse for reference?
hope your brewing continues uninterrupted for the forseeable future :coffee:?
 
It should give me about 3-4 hours of backup power in case I am doing some work in a panel and need to shut the power off for an extended period of time. We are off-grid, so our power goes out from time to time for this kind of thing and I dislike how these cheap UPS units you get from amazon/bestbuy only last like 5 minutes.
Sorry the AIMS stopped working. I know how much you like that inverter. I totally get the reason for not buying the cheap UPS's. Even some of the good ones that have battery expansion options don't provide as much time as an inverter/charger using a LFE pack.

I bought a Chinese UPS that requires a 24 volt external battery. I have a 280ah 24 volt pack made up of 8 280ah EVE cells. Literally enough power for days in the event of a power outage.

I am looking forward to what AIMS has to say. Please keep us posted.
 
Alrighty, so an update.

After trying to get everything to work, I gave up and let the thing sit overnight. Last night I turned on my power supply to see what would happen, and the unit didn't power up, to be expected.

Then, I don't think I changed anything, and it powered up!!!

So I turned it off and tried turning it on again, and it wouldn't power up.

Confused, now I suspected that the issue was the power switch, or something that has to do with telling the inverter to turn on. Knowing most of these inverters (aims, sigineer, foxpower, etc.) are identical, I went and grabbed my remote control panel for my Foxpower inverter, since the RJ45 port on the back goes to the main PCB...And I turned on the power switch on the remote panel AND IT TURNED ON!!!

Now, even more confused, I turned off the remote control panel switch, try the main power switch, and it is working flawlessly each and every time.


I disconnected my power supply and grabbed my BigBattery Owl, which I changed the fuse in (Oriley's only had 250a fuses, no 300a fuses) and connected it up. Inverter turned on no problem...Used a heat gun as a load, still no issues.

I connected it back up to my office, and still no issues.

What gives.

If it craps out on me again, I'll update the thread here...But certainly a puzzle to me.
 
It crapped out again.

I was across the room, next thing I know, the lights are FLICKERING LIKE A MACHINE GUN and the transfer switch was going absolutely wild in the inverter. After about 3 seconds, the fuse in the 12v owl blew, this time I replaced it with a 250a fuse because that is all that Oriley's had.

Took it back to the bench, fed it power with a bench supply, and still no luck turning it on. I'm going to let it sit like last time and see what happens.

Even if I do get it working, I'm done with this inverter. It's supposed to be the backup for over $3k in computers and stuff, and at this rate it's going to be the cause of it all getting ruined!

We already have called AIMS and left a voicemail with Tech Support.
 
For a stand alone inverter I recommend GoPower sine wave. Get a separate transfer switch, separate charger.

This is why I don't like these all-in-one units that seem so convenient. One part fails and you need the whole thing and it takes down the whole system.
 
It crapped out again.

I was across the room, next thing I know, the lights are FLICKERING LIKE A MACHINE GUN and the transfer switch was going absolutely wild in the inverter. After about 3 seconds, the fuse in the 12v owl blew, this time I replaced it with a 250a fuse because that is all that Oriley's had.

Took it back to the bench, fed it power with a bench supply, and still no luck turning it on. I'm going to let it sit like last time and see what happens.

Even if I do get it working, I'm done with this inverter. It's supposed to be the backup for over $3k in computers and stuff, and at this rate it's going to be the cause of it all getting ruined!

We already have called AIMS and left a voicemail with Tech Support.
How old is this AIMS? It does no sound good, hope they have good customer service and make it right for you.
 
We bought it in Nov 2020.

Contacted AIMS tech support, they are sending a replacement board. Since I'm opening it up, I void future warranties, but had the option of buying a second control board, so I did.

Longer post coming tomorrow, it's late and I'm tired haha
 
Man, That is one of the unit I was checking out 2 months ago on AMZ.
This not good that it broke after only 6 months, feel bad for other customers that cannot do troubleshooting so have to send the whole unit back on their on money to get it fixed.
 
Man, That is one of the unit I was checking out 2 months ago on AMZ.
This not good that it broke after only 6 months.
But (in the video) we fixed it with a new board in a matter of a few minutes!
 
But (in the video) we fixed it with a new board in a matter of a few minutes!
But other customers that do not have have the capability to do the repair like you can will have to spend quite a bit of their money to ship the unit back to be repaired, I will not be happy if I have to do that after 6 months.
 
advanced user repair is cool AND IMPRESSIVE!

i am avoiding AIMS inverter for now

unclear what type of fuse they use

using big LiFePO4 packs means big SCA
 
Does anyone know what the failure rate of these units are? That has to be taken into consideration. At one time I was seriously considering buying this unit but as it turned out I went in another direction with a 24 volt pack.

Since there are so many doing DIY projects, replacing a board should be easy...it should be easy for anyone. MPP Solar follows this policy as well and IMO it's a good one. No need to send the whole unit back if it fails. Replace the faulty board or component....done.
 
But (in the video) we fixed it with a new board in a matter of a few minutes!
But did you check the old board for a bad solder joint(s). When you pressed down on the CPU that was the first thing that came to my mind.
 
Does anyone know what the failure rate of these units are? That has to be taken into consideration. At one time I was seriously considering buying this unit but as it turned out I went in another direction with a 24 volt pack.

Since there are so many doing DIY projects, replacing a board should be easy...it should be easy for anyone. MPP Solar follows this policy as well and IMO it's a good one. No need to send the whole unit back if it fails. Replace the faulty board or component....done.
I have the Aims 24 volt 6000 watt split phase Inverter/charger. Has been working flawlessly for 5 years now. Wife back-fed it one time and blew main control board. Aims sold me new board and I replaced and all is good again. Just my experience for what its worth.
 
I have an AIMS 24v inverter/charger thats been running constantly for 3years...never an issue; although it is running off lead acid not lithium batteries and it is "only" an UPS, no daily cycling of batteries, no solar, just battery backup for all the network gear and my PC, about 600watts total.
It typically catches a power flicker or two daily, I think, excluding known events such as hurricanes where it gets powered down, its been running 24/7 with just a monthly topping off battery water.
I am giving the mppsolar+lifepo4 a try once the rest of my batteries arrive.
 
I have an AIMS 24v inverter/charger thats been running constantly for 3years...never an issue; although it is running off lead acid not lithium batteries and it is "only" an UPS, no daily cycling of batteries, no solar, just battery backup for all the network gear and my PC, about 600watts total.
It typically catches a power flicker or two daily, I think, excluding known events such as hurricanes where it gets powered down, its been running 24/7 with just a monthly topping off battery water.
I am giving the mppsolar+lifepo4 a try once the rest of my batteries arrive.
I was using sealed lead acid (gel matt) 4 years. Now using LiFePo4. Runs refrigeration & 220 well pump daily, and entire house if grid down. But then only sparingly.
 
I have the Aims 24 volt 6000 watt split phase Inverter/charger. Has been working flawlessly for 5 years now. Wife back-fed it one time and blew main control board. Aims sold me new board and I replaced and all is good again. Just my experience for what its worth.
I have same one, going on two years and counting with temperatures of 110 degrees Fahrenheit to 33 degrees below zero Fahrenheit it has still ran each morning I flip the switch to turn it on or the times I had to recharge or equalized the batteries.
 
Just to update everyone - after the repair this unit has been working perfectly fine, and we have a spare control board just incase something goes wrong again, which I doubt. Oh and I should mention that this was ONLY used in a ups-type application, no daily cycling back and fourth or anything. It was a relatively easy repair, much easier than changing a motherboard in a computer...Just plug everything into the same hole on the new board and take tons of pictures.
 
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