Server power supplies in series!

[auraslip]

Well the stack has worked great for many months, but it's developed a problem.

It'll push current for 20 seconds, and then one unit shuts down and flicks on and off for about 10 seconds before coming back online. Don't know what's causing it. It still works, but is just a slower charge.

Luckily, I have a spare unmodded unit, and another unused unit in the stack, so I just need to isolate the bad unit and swap it out.

[ZOMGVTEK]

Hmm. That's interesting.

Did you try hitting it really hard yet?

[auraslip]

Actually that's a good point. Before I was pushing the meanwell to it's max....

but on my new bike I made a mistake and made the charge wires from 22awg. And since it's like 6 feet long (through the rear rack and bag where it's stored all the way down to the triangle and then back up inside it) They were getting warm, so I turned the meanwell down to 4.5a. Maybe that's not enough power to make it stay on.

OTOH, if that were the case It'd be shutting down at the end of the charge cycle.

So to answer your question, no. These are rated at 12v60a, but I've only done 8a max.

[ZOMGVTEK]

Oh wow, 22 AWG charge wires? Even 4A is pushing that wire.

I wasn't speaking electrical, more physical. Hitting stuff thats broken sometimes fixes it in my experience. Sometimes it just makes it more broken.

A 60A supply should be happy supplying 4A or so, the only issue I could see is how the setup is being current limited. You sure the meanwell isn't doing funny stuff dialing down the current that low? You were running it for a while exactly as it sits I presume?

[auraslip]

Ran it for like 6 months until I adjusted the power down and started having problems. Will try to knock it with a mallet

[icecube57]

Ran it for like 6 months until I adjusted the power down and started having problems. Will try to knock it with a mallet

Some of those supplies have LVCs also...how low did you tune it....

[ZOMGVTEK]

Ran it for like 6 months until I adjusted the power down and started having problems. Will try to knock it with a mallet

Do you think it might have more to do with how the supplies are current limited, rather than the supplies themselves?

Limiting a bunch of series supplies with a single psuedo CC supply that makes up a minimal amount of the total series voltage is not like a lab power supply. It's limiting the current by limiting the voltage, which may or may not be possible for the voltage range of the supply and the range your pack can be in.

I'm suspecting the low current is the issue.

[auraslip]

Actually, the meanwell is a 48v unit. Remember when I first tried this I tried a 5v meanwell, and then a 24v, and finally only the 48v unit worked?

It's one of the 12v units that is acting up.

[ZOMGVTEK]

Ah, I thought you were running a 24V Meanwell. 48V should get the job done fine.

I could see an instance where the Meanwell could make some series supplies flip out, but it would be unlikely. Probably just a screwy supply.

[ZOMGVTEK]

Anyone ever see one of these before?



I just got a big lot of DPS-600PB's and there was a DPS-500FB in there. It's a 600W model with 2 more amps on the 12.15V line. Otherwise looks identical.