MP 1,1-5,1 Getting electrical tinges from touching Mac Pro 5,1 chassis

[yakult121]

Hello people, recently getting slight electrical tinges from brushing by or touching my Mac Pro 5,1 chassis. Its definitely not static.

Any ideas how to get rid of it? Attach a grounding cable from the metal chassis to earth?

 

[tsialex]

Hello people, recently getting slight electrical tinges from brushing by or touching my Mac Pro 5,1 chassis. Its definitely not static.

Any ideas how to get rid of it? Attach a grounding cable from the metal chassis to earth?

Did you check the polarity of the electrical power outlet? This change from country to country so you should check the correct polarity.

Do you have ground at the socket? I have frequent electrical shocks when the power outlet is not grounded.

 

[KeesMacPro]

Any ideas how to get rid of it?

It's definitely a grounding problem in the electrical installation (unless you connected a cable with socket without ground contacts).
If the house is not your property , I'd contact the owner of the place and claim it.
Normally in installations not any older than let's say 20 years or more there's a switch that detects grounding current leaks and switches the mains off immediately.
That is actually mandatory in at least 1st world countries...
Failing grounding can be deadly!

Attach a grounding cable from the metal chassis to earth?

No , dont do that.
Although that will be safer for you, but chances are that there will be current flowing through your MP > dead MP.

In case you want/have to solve it yourself, I'd put a copper pipe in the earth under the house and connect it to the main grounding wire of the electrical installation (where the fuses are).

 

[sfalatko]

Hello people, recently getting slight electrical tinges from brushing by or touching my Mac Pro 5,1 chassis. Its definitely not static.

Any ideas how to get rid of it? Attach a grounding cable from the metal chassis to earth?

So you are saying this has only recently started happening? If that is so what has changed? Has there been any electric work done on the circuit/load center/residence?

 

[yakult121]

Thanks guys for your replies! I have a three pin power cable so i think earth/ground are there (nonetheless, i'll get another cable to test). The only change that i've made to my Mac Pro is to replace a faulty PSU. I guess this replacement PSU has problems..

I need to figure out how to repair the faulty one... it's been sitting aside for the last two weeks.

Thanks again guys!

 

[JuanPC2021]

i have 2x MacPro 5,1 2010,

one had the electric tingles when touching, the other Not...

it´s the PSU, it´s failing...

Replace with another, exactly the same,
NOS or New...
it´s a Good Quality PSU, 80plus Platinum level...

80 Plus - Wikipedia

en.wikipedia.org

both my Apple MP 5,1 have different PSU...
the one i removed was:
DELTA ELECTRONICS, INC.
MODEL: DPS-980BB-2 A REV :00F
Apple part Number: 614-0454
12.2v 79A
5Vsb 5A.
MAX TOTAL CONT. OUTPUT POWER: 980W

the other Original PSU i have is different brand.

but....
i did a crazy thing... removed the Apple PSU and installed an ATX EPS12v PSU
eVGA T2 80plus Titanium level.
improvement was small -20w IDLE, -40w 100% LOAD CPU or GPU "GTX Titan 6GB"..
Effort level was crazy...

if you want to try replacing the Apple PSU for ATX EPS12v
#1. you need to remove & open the original PSU,
to desolder or cut the Apple cables as close to the PCB as possible..
also
i do Not recommend replacing with a standard Size ATX PSU,
go for SFF "Small Form Factor",
there are good models from Corsair SF and Silverstone 800w Titanium.
buy heatshrink tubing 3mm or 4mm if you want to solder cable to cable directly,
from ATX SFF PSU cable to Apple Cable.
wiring is complex.
see wikipedia for standard ATX EPS12v v2.3 pin-out,
most are Not needed for Apple Board, ATX EPS PSU are unnecessary complex.
Apple cables are easy to guess with a multi-meter, measuring turned off & turned on.

Apple has 1x 3.3vdc, and 2x that look close to 3.3vdc,
those are Thermistor PSU temperature sensing, Not needed, can be left floating, or can be connected to 3.3v with a variable or fixed resistor to emulate Thermistor resistance, some thermistors are 10k ohms, others are 50K,
if Temp sensing are left open / floating or connected directly to 3.3vdc, PSU Fan will spin 100%, needs MacsFanControl to lower fan speed or disconnect PSU fan, Not recommended.
ATX PSU have Fan, but having another fan is better, heat builds up because thermal design,
original design was axial / horizontal design front to back,
but most ATX EPS SFF PSUs are belly FAN, Not good for that case.
probably you need to move the 120mm psu fan from the back of the the grill to the front of the grill,
to make room for the SFF PSU cables, does Not have enough room for cables,
Apple cable management is very neat / minimalist.

ATX cables are too long, like spaghetti, you need to cut or buy shorter 24-pin ATX cables,
also CPU cables,
GPU VGA cables long are OK.

The problem with standard ATX size PSU is that Apple MacPro5.1
has a Aluminum Mesh to hold a 12v FAN for the PSU,
Apple PSU does Not have a FAN.
the PSU fan is on the Case in front of the PSU...
Removing that is near impossible,
better to leave the metallic grill.

you also need a shorter 1inch ATX PSU cable from cablemods for your PSU brand/model...
or cut the original 24-pin cables shorter "Not recommended." unless you buy replacements.

is complex.. it´s easy to install an Original Apple PSU.
TeamProFitcom has nice cables, dual mini 6-pin GPU to 8-pin GPU.

Mac Pro Pixlas Mod - The House of Moth

Modify your Mac Pro power supply to relieve the board and feed powerhungry GPU's

thehouseofmoth.com

Mac Pro Pixlas Mod, is it really needed?

I have been a vocal proponent of the Pixlas Mod. However I started doubting the claims my recommendation was based on and decided it was time to get to the bottom of this. Do I still recommend the Pixlas Mod after gathering all this information?

thehouseofmoth.com

 

[yakult121]

Thank you for the detailed write up! I will