[Virtalahde]

Originally Posted by HandCrafted Lab

are you professional circuit designer, DIY designer,device maker?

I know enough to be dangerous.

Originally Posted by HandCrafted Lab

these engineers not able to design grounding chains correctly?

Some manufacturers do provide separate banana jacks for signal ground (Manley Labs is one of them), and I'm about to modify my chain for transmission ground system, too.

But you're right in that some gear has terrible inner groundings. In my opinion, XLR pin 1 *always* goes to the chassis, the signal ground(s) go to one star ground point inside the chassis. Good folks also provide a way to disconnect the signal ground from the chassis and a way to bring it to a star ground point/bus of the entire system.

Grounding and Shielding Audio Devices

Originally Posted by HandCrafted Lab

You have used two correct key words - If... & And.
It`s alike - "your car can (or should?)to explode because car engine use gasoline - which is flammable". Yes,of course - if you smoke near of the gasoline tank or push up the stump/match into this tank.

"If" & "and" are perfect words when we're talking human lives here. That's why safety standards are for.

Originally Posted by HandCrafted Lab

Yes, and this switch connect IEC ground pin to the chassis directly - if need.

And that is simply the wrong and illegal way to do that. I'm sorry, but it's exactly the same thing electrically as putting masking tape on your mains cable's safety ground lug!

There's another point in that system. Even if that switch (looks like a basis Apem switch or whatever) is connecting the safety ground to the chassis, I believe that those contacts, even in parallel, are NOT able to conduct full 16A (or more) to the chassis in the event of an catastrophic failure.

I'm sorry man, but what you're doing here is simply illegal, dangerous and just plain wrong. In some of your equipment, it looks like you're providing the user a way to disconnect every ground out of the system. If something fails inside and live mains voltge comes to connection with the chassis, the fuse is not going to blow if all ground lifts are in.

Originally Posted by HandCrafted Lab

But colleague - IEC rules not describe ground & digital loops, hums/noices for studio audio devices. Look, it`s not chinese teapot,razor or toaster.

Whether made in Ukraine or not, audio equipment is still perfectly capable of killing people if not designed correctly. It does not differ from chinese toasters in that way.

IEC rules perhaps don't describe ground loops, but they do describe basic electrical safety and that means the safety ground always goes to the chassis, period.

Originally Posted by HandCrafted Lab

Ground pin in the IEC socket is not grounding actually. It`s zero bus,in addition to hot and cold power lines. This zero bus can help to avoide an electical shock but this zero bus has widest spectrum of noises from different sources which is grounded through same IEC grounding across your power lines - from all your digital devices in studio to welder machines and lathe on the nearest plant,drills,microwaves etc near of your location.

Of course it's all relative when we're talking about grounds. Still, it's perfectly possible to make a low noise installation and still be perfectly safe. I run an unbalanced system in an industrial building. There's a lot electric noise-making machinery around, and none of it makes it to my system - if you don't count what happens below -110dBFS.

Originally Posted by HandCrafted Lab

Therefore... never use both variants of grounding simultanesously - firstly it has not any sense,secondly - you will not damage stuff and save money.

There are multiple installation techniques around that provide a way to organize your grounds properly. I talked earlier about separate banana jacks that separate signal ground from safety ground/chassis, and that one you can connect how you wish to.

The thing is.. You're talking about whole grounding systems but you're still selling individual pieces to individual customers. You just don't know how they're installed. That's why the safety ground is there, it's there for safety, to make sure no-one gets killed if the unit fails or someone does something stupid.

Disconnecting the safety ground with a switch designed for relatively low currents isn't better or more "right" than putting masking tape on your IEC connector.

If someone gets injured or dies when your equipment puts 230v through the user, it is you who is responsible if your equipment is built wrong.