Is it feasible to connect 5 ATX PSUs in series to get 60v?

[JovanD]

This is assuming i make sure the - on 12VDC output is not connected to ac plug ground.

I seen people on the internet make 24v by connecting 2 PSUs, but i need 60v.

Im asking here just to make sure it will work since i know PSU's work a bit different than batteries.

[whispous]

Why are you needing to do this?

[Hinjima]

5 minutes ago, whispous said:

Why are you needing to do this?

For the rumored 4090 Super.

[JovanD]

Just now, whispous said:

Why are you needing to do this?

I want to connect my electric moped to a generator, the moped runs on either 48V or 60V, but only 48V PSU's i can find are for led strips and not powerful enough and too expensive, so i figured used ATX psu's would be most economic option since i only need 20A per PSU.

And reason for doing that is because the original lead acid batteries got damaged (probably age, imbalance, overcharging), they puffed up and don't hold much range, so im but sceptical of using them.

I already ordered a nice LiFePo4 battery, but it will take at least 2-3 months to arrive, so i need a temporary solution to get decent range.

[JovanD]

7 minutes ago, Hinjima said:

For the rumored 4090 Super.

Seems like GPUs are outgrowing the 12v standard, if it continues like this, we're gonna need car jumper cables to connect the GPU's 

[Hinjima]

8 minutes ago, JovanD said:

Seems like GPUs are outgrowing the 12v standard, if it continues like this, we're gonna need car jumper cables to connect the GPU's 

Someone actually built this thing as an April Fools before the 4000 release when it was rumored to hit 600-700w   Maybe you are correct in a few years ^^

But yeah, can't help you with your question sadly, I am not very good when it comes to electrics like that. Good luck!  

[JovanD]

The thickness doesn't seem too far off from the real thing

[da na]

Sounds like a pretty bad way to get 60v, but I'm sure you could do it. Why not just use a transformer? 

Also, you get a charge controller for those LiPos? Just want to make sure.

 

[FloRolf]

@manikyath this sounds like a topic you'd be interested in 

[OhioYJ]

Wouldn't a 60 Volt power supply cost about the same as 5 power supplies anyways? Not to mention take up a lot less room, and make this much simpler?

 

How much current do you need?

 

Here is an adjustable example.

 

Fixed style example.

[JovanD]

29 minutes ago, OhioYJ said:

Wouldn't a 60 Volt power supply cost about the same as 5 power supplies anyways? Not to mention take up a lot less room, and make this much simpler?

 

How much current do you need?

 

Here is an adjustable example.

 

Fixed style example.

I need about 20Amps and im considering getting used PSU's for about 5eur a piece (cheapest i can find) since my budget is 30eur, not 300eur so 60v psu is not gonna cut it, that's why the DIY serial method.

[Alex Atkin UK]

1 hour ago, JovanD said:

The thickness doesn't seem too far off from the real thing

Yeah, but the real thing does actually squeeze into some three slot ITX cases.

[manikyath]

9 hours ago, FloRolf said:

@manikyath this sounds like a topic you'd be interested in 

i've actually done this before...

 

on that note, yes and no.

yes - you can do this.

but no, dont. this is EXTREMELY dangerous, you have to disconnect the earth lead from all but the first psu's power cord, insulate or remove all but the first psu's chassis, you cant bolt them together with anything conductive or you'll have 48 volt dead shorts, etc...

 

MeanWell probably makes something you can use either in a single psu form, or two in parallel.

 

also.. if you're doing this to replace a 60v lead acid pack.. lead acids are dirt fcking cheap...

[manikyath]

19 hours ago, JovanD said:

the moped runs on either 48V or 60V, i only need 20A per PSU.

60 volts is a problem for MeanWell apparently, but 48 volts has plenty of choice;

 

https://eu.mouser.com/ProductDetail/MEAN-WELL/UHP-1500-48?qs=XeJtXLiO41Q5%2FLaLUsa1%2FA%3D%3D

https://eu.mouser.com/ProductDetail/MEAN-WELL/SE-1500-48?qs=l0g2inPJSHML6gMN8U2Smg%3D%3D

https://eu.mouser.com/ProductDetail/MEAN-WELL/NSP-1600-48?qs=Li%2BoUPsLEntZJJHjPkSMvA%3D%3D

 

there's also this 55 volt unit, but that's exceptionally expensive.

https://eu.mouser.com/ProductDetail/MEAN-WELL/HEP-2300-55?qs=t7xnP681wgWNs1mLcP1Qqg%3D%3D

 

19 hours ago, JovanD said:

the original lead acid batteries got damaged

you're well awara that lead-acid batteries are dirt cheap right?

assuming it's a 4-pack of the bog standard formfactor that's also in UPS'es, you're only looking at 80 bucks or so for a fresh set of batteries. (or to be honest.. if they'll take the punishment until your LiFePo arives.. which, just so you know, it's not a straight up drop in replacement in a lot of cases..)

 

at least going with either of these options doesnt require any of the below...

20 hours ago, JovanD said:

a generator

Quote

5 ATX PSUs in series

9 hours ago, manikyath said:

disconnect the earth lead from all but the first psu's power cord

9 hours ago, manikyath said:

insulate or remove all but the first psu's chassis

9 hours ago, manikyath said:

48 volt dead shorts

18 hours ago, JovanD said:

used PSU's for about 5eur a piece

 

the thing is.. what you are planning can be done, but it sounds ridiculous, dangerous, impractical, and possibly reason for the police to remove your moped from the road... (which in most EU countries i'm aware of, they can do if they have a strong indication that the current form of the vehicle will not pass inspection)

 

something else to consider is, if any of your second hand bangers has a slight defect in primary - secondary insulation.. that's an electrical fire. you know the occasional tingles some phone chargers can give you? that's risk for a dead short if you like multiple PSU's in series.

 

what i'm telling you.. is to push your budget to €100 for a set of batteries, to avoid a potential €150 fine if the po-po sees you drive around with this nonsense.

 

also;

19 hours ago, da na said:

Also, you get a charge controller for those LiPos? Just want to make sure.

i just want to add that it felt like this was skipped over.. and this should not be skipped over.

[JovanD]

The LiFePo4 battery i ordered is a pack that comes in a metal case with BMS good for 100A (continuous) discharge and comes with a 10A charger, it cost me 700eur with shipping, but im banking on the long cycle life of LiFePo4 cells to make it worth it hopefully  im also bit broke right now (because i ordered the battery) and because wages here are quite subpar .

And yes im aware of the possible legal issues, in not in EU, im in Serbia where cops are cheap(10-20eur) to bribe, but than again my moped is in the weird legal "gray zone" where it's officially classified as an "e-bike" and motor power has been declared as "250w" although im pretty sure its more than that  

Now that i think about it i will just wait it out since it's not worth it to me to mess with traffic court, especially since i don't have any drivers license.

Although in the meantime i managed to jerry rig the moped to run on 3 cordless power tool batteries i had (i 3d printed the adapters), the range is really bad, barley 8-10km, but good enough to get me to work and i don't have to worry about lead acid pillows.

Anyway thank you guys for telling me its a bad idea.