XLR shared ground

[Guest]

i want to build a universal power supply for my "pc room" where i can plug in my phone at 5v, and my other projects at 12v and XLR has three pins, so my question is: can i share 12 and 5v ground? or do i need to scrap the 5v pin?

[SydneySideSteveSomewheres]

You could use 12V car batteries, basically, you would just hook up an automotive battery charger to them. That way if you need to supply a different voltage to as you say a phone it would just be a matter of wiring in a car cigarette lighter socket. This would give you a connector that has a potential to be able to connect a multitude of other usable devices. Just be wary that the cigarette lighter type USB converters (the jack) their circuitry draws current as soon as they are plugged, so you might want to include a plain old toggle switch to stop that!

 

Traditionally UPS use batteries that are Sealed Lead Acid (SLA) or Gel cells as their rechargeable sustainable power source.

 

Nb: If you use car batteries they are lead-acid and off-gas hydrogen from the electrolysis principle of converting electrical energy to stored energy. This gas is flammable and these batteries should be kept well ventilated (outside is best!) and away from naked flame or explosions could occur...

 

[Guest]

2 minutes ago, SydneySideSteveSomewheres said:

You could use 12V car batteries, basically, you would just hook up an automotive battery charger to them. That way if you need to supply a different voltage to as you say a phone it would just be a matter of wiring in a car cigarette lighter socket. This would give you a connector that has a potential to be able to connect a multitude of other usable devices. Just be wary that the cigarette lighter type USB converters (the jack) their circuitry draws current as soon as they are plugged, so you might want to include a plain old toggle switch to stop that!

 

Traditionally UPS use batteries that are Sealed Lead Acid (SLA) or Gel cells as their rechargeable sustainable power source.

 

Nb: If you use car batteries they are lead-acid and off-gas hydrogen from the electrolysis principle of converting electrical energy to stored energy. This gas is flammable and these batteries should be kept well ventilated (outside is best!) and away from naked flame or explosions could occur...

 

but i want to plug it into the wall, not via batteries, i'm planning on using a picopsu or a normal psu

[Factory Factory]

Yes, they can share ground. Unless you specifically want a floating-ground application (like using an oscilloscope on a battery-powered item), ground is common. As in, one ground to rule them all.

 

This doesn't work on AC since AC doesn't have ground the same way. Hot and neutral cannot be made common with DC or with other types of AC power. However, if you're using three-prong AC, the ground pin can be made common with all the other ground in the project (and it is generally good for safety to attach the ground pin to the casing of the project so that no voltage buildup occurs that can give the user a nasty shock).

[Huntsman]

Ground is common for DC. Unless you want to floating ground. However, a XLR connector is a terrible choice for this. If you accidentally plug in audio equipment into it, be prepared to cry as much tears as the equipment costs.

[Guest]

5 hours ago, Huntsman said:

Ground is common for DC. Unless you want to floating ground. However, a XLR connector is a terrible choice for this. If you accidentally plug in audio equipment into it, be prepared to cry as much tears as the equipment costs.

wow, that is just the reason that i chose this over usb

[Ahoy Hoy]

Could use a 5 or 6 pin XLR and have separate grounds

[nuttytechy]

I personally would not use XLR for any form of power. What concerns me the most when people use an XLR for any form of power is cable size, Electrical resistance etc. If you are using one of the pins for a 5volt and another for a 12 volt then yes its possible as even though an 3 pin XLR has the 3 connectors, There is a 4th and thats the outer plug, That can be used as a ground. We use that when we run balanced audio cables. 

 

The issue im going to bring up. You will have 2 leads within the plug which will be 2 different voltages. The only snag will be is how much of a load. You said 12 volt projects. As I do not know what they are. You will need to remember the load being put through those cables. The higher the load the more heat which will dissipate from those leads. I dont want to scare you and say it could start a fire but the bottom line is that when you doing your own cables you need to take that into account. 

 

I know some of you are going to say. This product has a thin cable but runs at 5 volts.... Yes it does but it has a low current load - say 5 milliamps etc so it wont give off much heat.