Author Topic: PSU question  (Read 708 times)

Offline Xmas!

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PSU question
« on: January 25, 2019, 09:55:13 AM »
So I am drawing a complete blank trying to make sense in my head about something. Are the V+ outputs on ONE power supply connected as 1 circuit? Or are they each individual circuits? I am looking into using a different kind of fuse block for the V+. The real question is, can I take all three V+ from a single power supply and combine them on a 1 input/3 output fuse block?
My name is Steve and I'm just getting started. but I think this will become a huge hobby!!

Online Poporacer

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Re: PSU question
« Reply #1 on: January 25, 2019, 10:17:13 AM »
Most power supplies have a common V+. You can verify this if you disconnect power and then test continuity on those ports. If they are connected then you will only need to connect one V+ port to your fuse block. Make sure you choose an appropriate size wire!
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Offline Xmas!

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Re: PSU question
« Reply #2 on: January 25, 2019, 10:29:37 AM »
Most power supplies have a common V+. You can verify this if you disconnect power and then test continuity on those ports. If they are connected then you will only need to connect one V+ port to your fuse block. Make sure you choose an appropriate size wire!


Thanks once again Pop. I am planning on using 10awg wire (30 amps). But if they do have continuity, wouldnt it be better to run 10awg wires from all 3 V+ outputs to a block since I will be using 3 outputs from that block?

Online Poporacer

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Re: PSU question
« Reply #3 on: January 25, 2019, 12:01:24 PM »
It really wouldn't be better. If the wire can handle the amperage, adding more won't let you pull any more power. And 10 AWG wire is pretty big, you could probably get away with something smaller. Based on wire size alone and voltage drop, you could use 16AWG wire, but the insulation might not be rated for that.

Offline Xmas!

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Re: PSU question
« Reply #4 on: January 25, 2019, 12:11:46 PM »
The PSUs and F16 are rated for 30A so thats why I used 10awg.

Offline Kringle

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Re: PSU question
« Reply #5 on: January 25, 2019, 02:46:03 PM »
From my experience in the industrial maintenance field the reason there is multiple V+ and V- on a power supply is because they are usually used to power multiple things.  With 3 output you can run say 2 wires to each V+ to feed 6 different devices.  It allows for not having to putt say all 6 wires on one terminal.  Not sure if this is the actual reason for it, but its the way I see most engineers utilizing it.  Having all 3 out puts to one fuse block basically would be a redundancy in case 1 or 2 wires got cut somehow.

Offline Xmas!

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Re: PSU question
« Reply #6 on: January 25, 2019, 03:42:52 PM »
Roger that. Thanks.

Offline JonB256

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Re: PSU question
« Reply #7 on: January 26, 2019, 06:08:03 AM »
I have yet to find any of the "Meanwell" style PSUs that have isolated V+ outputs.
There are a lot of computer power supplies that will do that (they will call them "rails") for +5vdc outputs.

Offline Stormyblade

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Re: PSU question
« Reply #8 on: March 11, 2019, 02:00:31 PM »
It really wouldn't be better. If the wire can handle the amperage, adding more won't let you pull any more power. And 10 AWG wire is pretty big, you could probably get away with something smaller. Based on wire size alone and voltage drop, you could use 16AWG wire, but the insulation might not be rated for that.


After reading through this topic, I am curious how you attach a 10awg wire to the outputs of the PSU? Any lug/terminal you would use on this wire would be far too big to fit on, or under, the screw terminals, correct? I used 12AWG wire and had to trim down the lugs so they could fit, and I was very concerned I would be creating a hot spot at that connection point.

Offline thaistalyn

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Re: PSU question
« Reply #9 on: March 11, 2019, 07:09:50 PM »
I have terminal kit from Amazon-->  https://amzn.to/2XS60OD and use the yellow forks  (bottom left on the Amazon picture) for connection to my power supply with 10AWG wire. The wire fits easily into the fork and the fork fits in the power supply slot just fine.


The OP (Xmas/Steve) posted a build of his enclosure and he actually uses spade terminals (first yellow connector top row in the Amazon pic) to connect to his power supply and distro block.  He added a spade connector on the power supply side - here is a link to the spade stud that can be permamently mounted to the powersupply --> https://amzn.to/2u3AbVm




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Offline Stormyblade

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Re: PSU question
« Reply #10 on: March 24, 2019, 11:43:43 AM »
I have terminal kit from Amazon-->  https://amzn.to/2XS60OD and use the yellow forks  (bottom left on the Amazon picture) for connection to my power supply with 10AWG wire. The wire fits easily into the fork and the fork fits in the power supply slot just fine.


The OP (Xmas/Steve) posted a build of his enclosure and he actually uses spade terminals (first yellow connector top row in the Amazon pic) to connect to his power supply and distro block.  He added a spade connector on the power supply side - here is a link to the spade stud that can be permamently mounted to the powersupply --> https://amzn.to/2u3AbVm

I may have missed his build thread and pics. Thanks for sharing that info!

 

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