Any harm in chopping off unrequired PSU connectors?

[Coup27]

I have put together a Haswell PC using a Seasonic SS-360GP Gold PSU. I chose this because the user wanted a 24/7 PC with high quality parts. They also wanted it in an m-ITX case. I am really struggling to squeeze it all into the case without a cable fouling the HSF or adding strain to those awfully loose internal USB3 header connections. Anybody who has built a m-ITX using a full size PSU will understand my pain.

Although this sounds drastic, this PC will never be expanded. I was thinking of cutting off the PCI-Express 6 pin and all of the traditional 4 pin molex connectors and taping the ends up with electrical insulation tape.

I wanted to check first that this will not cause any issues? Personally I can't see how it would, but I don't know if there are any electronics in the connectors themselves such as a resistor which completes the circuit which I'll remove if I cut them off.

 

[Flapdrol1337]

kills the warranty, just squeeze harder

 

[Hail The Brain Slug]

Well, if you don't care about voiding the warranty, you might as well break open the power supply and cut the wires from the PCB directly. That way you won't have any loose wires going anywhere for anything and it's been made end user-proof.

 

[Red Squirrel]

Well, if you don't care about voiding the warranty, you might as well break open the power supply and cut the wires from the PCB directly. That way you won't have any loose wires going anywhere for anything and it's been made end user-proof.

This. Also give enough slack so that in the future you can always just connect it back with wire nuts or something.

 

[DigDog]

just MAKE SURE YOUR PSU IS FULLY DISCHARGED before you open it.

https://www.google.co.uk/?gws_rd=cr&ei=VkKDUsqQJs2KswblqIH4Aw#q=how+to+discharge+a+psu

 

[Charlie98]

I have put together a Haswell PC using a Seasonic SS-360GP Gold PSU. I chose this because the user wanted a 24/7 PC with high quality parts. They also wanted it in an m-ITX case. I am really struggling to squeeze it all into the case without a cable fouling the HSF or adding strain to those awfully loose internal USB3 header connections. Anybody who has built a m-ITX using a full size PSU will understand my pain.

Although this sounds drastic, this PC will never be expanded. I was thinking of cutting off the PCI-Express 6 pin and all of the traditional 4 pin molex connectors and taping the ends up with electrical insulation tape.

I wanted to check first that this will not cause any issues? Personally I can't see how it would, but I don't know if there are any electronics in the connectors themselves such as a resistor which completes the circuit which I'll remove if I cut them off.

In lieu of just chopping the wire and using black tape (and assuming you don't want to go into the PSU itself, although that is probably the best idea...) you can also use terminal crimp caps... they don't get all hot and melty like black tape does in a hot PC case.

Personally, I'm right there with you... especially for all those unneeded Molex connectors.

 

[Coup27]

Nice idea on the end caps, thanks.

 

[Charlie98]

Nice idea on the end caps, thanks.

Just remember to use a gauge-specific crimper to crimp them... and then give them a pretty good tug to make sure they don't come off. Stranded wire, especially smaller wire, can be a bit of a booger to try to crimp down securely in terminal or butt connectors. You do NOT want one of those caps coming off after the end user gets the machine.

 

[spat55]

I'd just keep them just in case one of those wires touches the case and someone touches the case! I for one wouldn't be a fan of opening the PSU.

 

[Red Squirrel]

Opening a PSU is not really a big deal. It's not like a TV where there's extremely high voltages inside. There's the big capacitors which may still hold 120 but it feels funny more than anything if you do happen to swipe your hand on them.

Depending on how the wires go to the board you can even just desolder them. Sometimes they all combine together in one spot so just find the ones you don't want and desolder them. Chances are they'll all come out but you can just resolder the ones you want.

 

[serpretetsky]

Opening a PSU is not really a big deal. It's not like a TV where there's extremely high voltages inside. There's the big capacitors which may still hold 120 but it feels funny more than anything if you do happen to swipe your hand on them.

I don't have statistics, but I would still treat 120 with respect. Most likely you'll feel a discomfortable feeling, but there is always that chance you get a good path right through your heart and end up in a hospital.

 

[Coup27]

I live in Europe so I'd get the full 230VAC instead!

I've let this thread continue because it's interesting to see peoples comments, however I decided to overhaul the cabling routing and finally found a way of shoe-horning it all in.

 

[serpretetsky]

I live in Europe so I'd get the full 230V DC instead!

fixed, unless you were operating in your PSU with the power still plugged in :O .
Caps do not provide AC by themselves.

 

[Red Squirrel]

I don't have statistics, but I would still treat 120 with respect. Most likely you'll feel a discomfortable feeling, but there is always that chance you get a good path right through your heart and end up in a hospital.

Oh definitely, but if it's turned off and you actually discharged it odds are there wont be much energy left in there.

 

[mindless1]

1) Whether 120VAC or 240VAC the caps usually get to a little under 400VDC from rectification and/or doubling.

2) PSU practically always have bleeder resistor(s) to discharge the high voltage cap(s) but even if they didn't then the 5VSB circuit, even powering nothing, would drain them to a safe voltage within a few seconds, a far shorter amount of time than it takes to open the PSU.

3) Rather than bulky and expensive end caps or tape that can get sticky and come loose, I'd use heatshrink tubing, and fewer pieces, bundling together 2 or more wires of the same type (per rail, per voltage, and the grounds) instead of a separate cap on every wire. That could end up cheaper (except shipping is a wildcard for a one-off project order), take up less space, and be less prone to rattling around.

You could desolder the wires but often that takes a really beefy soldering iron and the structural integrity of the PCB may be compromised if single sided and there are a lot of open holes and some strain on the remaining wires. It seems like it's a low benefit to work ratio.

 

[Galatian]

Maybe a stupid suggestion: if you can still give it back, can't you exchange it for a modular PSU?

 

[philipma1957]

I don't have statistics, but I would still treat 120 with respect. Most likely you'll feel a discomfortable feeling, but there is always that chance you get a good path right through your heart and end up in a hospital.

I was changing a 4 foot ceiling florescent bulb.

Did it live since I was been lazy.

Hot sweaty and I got a full shot of juice from my left and across my chest to my right hand.

Felt some weird pains in my sweaty armpits,but my heart felt like

A) it was squeezed by a really big hand.
B) it felt sore for about 2 or 3 hours after it happened.


Never again. No live work on anything and I wait for all caps to discharge.