Static & Grounding? Confused

[hihihi8]

Today, after taking off my coat, I habitually grounded myself on my PC's chassis. The PC was on and running while i did this, and the moment I touched the case, some serious static discharge occurred. At the same time, my Aquaero 5 LT Fan/Pump controller disappeared from my windows interface but then reconnected. The Aquaero is screwed into the chassis by the grounding screws, and the case is grounded to the power supply. The system itself didn't flinch/freeze and works fine, but I'm confused as to why the static had an impact on my grounded components. Isn't the current supposed to go directly through the case into the ground via PSU? Could anyone clarify for me? I'm a bit worried about my Aquaero atm. Thanks! 

[WereCat]

When I touch my case and I get zapped and my PC is off then LED on my keyboard will turn on.

 

[manikyath]

if that's connected by USB, USB is stupidly sensitive.

[hihihi8]

1 minute ago, manikyath said:

if that's connected by USB, USB is stupidly sensitive.

yep, the aquaero is connected to windows via usb interface

[fjdhdhcyfhf]

2 minutes ago, hihihi8 said:

yep, the aquaero is connected to windows via usb interface

Is it connected to the internal motherboard USB, back panel, front panel? I always thought io shields were crap for grounding I guess you might have proof of it. In electrical work we bolt everything to copper wire but in a pc only the psu is connected to earth with copper and the rest Is grounded through a steel case coated in non conductive paint! The psu is also painted and sometimes sits on rubber

[hihihi8]

3 minutes ago, SCHISCHKA said:

Is it connected to the internal motherboard USB, back panel, front panel? I always thought io shields were crap for grounding I guess you might have proof of it. In electrical work we bolt everything to copper wire but in a pc only the psu is connected to earth with copper and the rest Is grounded through a steel case coated in non conductive paint! The psu is also painted and sometimes sits on rubber

It's connected through internal mobo usb pins, so i guess it found an easier path to ground via the ground plane of the Aquaero --> molex power connector --> PSU?

But that still doesn't really explain why my aquaero blacked out for a moment..

[fjdhdhcyfhf]

3 minutes ago, hihihi8 said:

It's connected through internal mobo usb pins, so i guess it found an easier path to ground via the ground plane of the Aquaero --> molex power connector --> PSU?

But that still doesn't really explain why my aquaero blacked out for a moment..

I can't really use anything more than a multimeter coz the voltage will destroy things. It won't think it would be grounded but just connected to the reference 0v. I might be wrong

[rhyseyness]

1 hour ago, hihihi8 said:

It's connected through internal mobo usb pins, so i guess it found an easier path to ground via the ground plane of the Aquaero --> molex power connector --> PSU?

But that still doesn't really explain why my aquaero blacked out for a moment..

Putting 10kV+ on the ground line (which is possible), would definitely cause your Aquaero to black out for a moment 

[fjdhdhcyfhf]

3 minutes ago, rhyseyness said:

Putting 10kV+ on the ground line (which is what you did), would definitely cause your Aquaero to black out for a moment 

if you put any voltage to the ground line it should function normally. If it wasn't grounded properly it will play up. That's all the ground is a pathway for unwanted and dangerous energy

[hihihi8]

3 minutes ago, SCHISCHKA said:

if you put any voltage to the ground line it should function normally. If it wasn't grounded properly it will play up. That's all the ground is a pathway for unwanted and dangerous energy

What i was thinking, however it should be grounded properly, as if it were not, my PC would probably be dead now from that huge arc. The PC itself didn't freeze or anything, it was chill enough to display a message saying that the aquaero usb device had disconnected/reconnected lol

[fjdhdhcyfhf]

1 minute ago, hihihi8 said:

What i was thinking, however it should be grounded properly, as if it were not, my PC would probably be dead now from that huge arc. The PC itself didn't freeze or anything, it was chill enough to display a message saying that the aquaero usb device had disconnected/reconnected lol

Yea to be honest the psu is not something I have looked into in great deal but I have dealt with other switch mode power supplies and I know a few things like a good quality design has high voltage circuitry a good distance from the electronics and electrical regulations only require the case around the high voltage to be earthed. Nothing else needs to be earthed just the psu to be electrically safe in terms of regs. In a double insulated device like a mobile charger nothing is connected to earth because it doesn't have to be. That's why Iv always guessed computer io shields were useless. I can't imagine the 0v lines would be connected to earth coz that would destroy its purpose of being the 0v reference, electrical earth can be at any v relative to what you are checking it against

[rhyseyness]

29 minutes ago, SCHISCHKA said:

if you put any voltage to the ground line it should function normally. If it wasn't grounded properly it will play up. That's all the ground is a pathway for unwanted and dangerous energy

If you put voltage on the ground line, you're pulling your ground up.

This means that any voltage in your system which is referenced to that ground is gonna be wrong.

The ground is most definitely not a "pathway for unwanted and dangerous energy." That's an earth, they're very different.

[hihihi8]

2 minutes ago, rhyseyness said:

If you put voltage on the ground line, you're pulling your ground up.

This means that any voltage in your system which is referenced to that ground is gonna be wrong.

The ground is most definitely not a "pathway for unwanted and dangerous energy." That's an earth, they're very different.

wouldn't that mean a big reverse current through the entire system? As "Ground" would be 10kV, and 12V would be the lower side

[rhyseyness]

1 minute ago, hihihi8 said:

wouldn't that mean a big reverse current through the entire system? As "Ground" would be 10kV, and 12V would be the lower side

Precisely, but it was his case, which is only the ground for his Aquaero, not the entire system.

The rest of the system will use a reference ground from the PSU, not the earth (chassis).

[hihihi8]

1 minute ago, rhyseyness said:

Precisely

rest of the system remained stable though

[rhyseyness]

Just now, hihihi8 said:

rest of the system remained stable though

Just editied my previous post for clarity

[hihihi8]

3 minutes ago, rhyseyness said:

Precisely, but it was his case, which is only the ground for his Aquaero, not the entire system.

The rest of the system will use a reference ground from the PSU, not the earth (chassis).

The aquaero doesn't actually use the case as the ground though, its circuitry is powered by a molex connector (5v GND GND 12V)

[fjdhdhcyfhf]

10 minutes ago, rhyseyness said:

If you put voltage on the ground line, you're pulling your ground up.

This means that any voltage in your system which is referenced to that ground is gonna be wrong.

The ground is most definitely not a "pathway for unwanted and dangerous energy." That's an earth, they're very different.

Yes your right I mixed the words up

[rhyseyness]

1 minute ago, hihihi8 said:

The aquaero doesn't actually use the case as the ground though, it is powered by a molex connector (5v GND GND 12V)

I'd have thought the same thing, but one of the signals in the Aquaero is obviously connected to the chassis, as it's adversely affected when the chassis is pulled high/low.

[rhyseyness]

2 minutes ago, SCHISCHKA said:

Yes your right I mixed the words up

I do the same thing sometimes, and it's my job 

[hihihi8]

11 minutes ago, rhyseyness said:

I'd have thought the same thing, but one of the signals in the Aquaero is obviously connected to the chassis, as it's adversely affected when the chassis is pulled high/low.

I see, thank you for clearing it up for me! So If i insulate the chassis and aquaero with say, nylon screws and ceramic washers, I can continue to use the case as a grounding point without affecting my aquaero, true?

[fjdhdhcyfhf]

8 minutes ago, rhyseyness said:

I do the same thing sometimes, and it's my job 

We use it interchangeably depending on who we talk to. On 230v ac appliances ground is earth

[rhyseyness]

51 minutes ago, hihihi8 said:

I see, thank you for clearing it up for me! So If i insulate the chassis and aquaero with say, nylon screws and ceramic washers, I can continue to use the case as a grounding point without affecting my aquaero, true?

Should do!

Glad I could help