DIY power cable questions

auxinput1,976 posts03-22-2020 12:36pm


Even if the power cord/connector uses all 3 conductors, the equipment it's plugged into will not use the ground conductor. All is good.

 A question on floating grounds?? 

I have a two 1200 watt DSP plate amps from PE, the same thing you just mentioned. How does it get a ground? Floating? There is ZERO floor noise. I haven't had any problems, but could I? I was gonna make up a good PC for the two, plate amps. There is no safety issue? Mixing grounded with a floating ground? Can there be issues? Hope I'm not off topic.

How do you weave a cable with no ground wire, to eliminate noise, I understand how "IT" works, just wondering what to do in lue off it?

Regards The OldHvyMec..

well, the neutral wire is basically the same thing as ground.  At your main junction box or circuit breaker box, neutral is wired into the ground anyways (wired to a rod stuck into the earth).  The neutral wire is almost like a "drain" for the hot wire, since you need a return wire for A/C or even DC voltage.  You can actually get shocked if you touch a neutral wire that has current flowing through it (i.e. it's connected to a device that's using "HOT" current).   However, the third ground wire will never usually have current flowing through it (or at least a lot of current). 

When making a power cord for an equipment that doesn't use ground, you could just use two conductors if you wanted and everything will be fine.  Or you could build or use a true 3-conductor power cord.  In this situation, the ground conductor is not connected to anything in the equipment.  But the ground conductor is still connected to ground at the outlet.  If you do this, the ground wire can act as an additional shielding or EMI capture (since it allows any EMI or voltage to be shunted to ground.

There is no safety issue here.  You can safely use a 3-conductor power cord on a plate amp that only has 2-conductor floating ground circuit.

You might want to google "floating ground".  It can relate to the ground plane within an electronic equipment where all extraneous voltages are shared.  This includes the ground plan shared between equipment through the ground shield of interconnects.

You might want to google "floating ground".

You know I did, I need to look a little closer. Thanks for the info..
Pretty short, said something about floating voltage too.
Safe is always a concern. thanks

Regards

I appreciate everyone’s feedback. 
auxinput, 
Thank you very much for answering my question. After doing a little more research I came to the same conclusion as what you suggested but it’s nice to hear it again for confirmation. Your post was spot on. ;)  

 I`ve done simple (minimum)12awg shielded solid core pc`s since the 90`s. Outperforms anything else no matter of price. None of my cables are flexible, flat, twisted or in fancy colours. They just sound perfect.