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Need help grounding some exposed metal.

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RisingFire

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Ok, i have some sheet metal and some metal braces
and some metal screws that i feel are creating dangerous static electricity.

this is what i made

its a dance pad for the game dance dance revolution on the playstation.

https://www.angelfire.com/d20/ddrhomepad/

The arrow panels have wires that connect to a directional circuit and a ground circuit within the playstation controllers PCB.

everything works fine and all once its wired up.

but after a while, the controller gets fried somehow.
i've tried many different controllers and many different soldering irons with different wattages.

then i thought maybe its the static electricity coming from people stepping on the sheet metal and pieces of plastic rubbing, and people stepping on the plastic.

I figured the easiest way to ground this is to somehow use the 3rd prong in a wall outlet... but i nkow nothing about electronics really.




can i take a grounded power cord...

cut off the female end...

find the wire that connects to the half circle male end that goes into the wall for grounding...

cut off the other male pins for the HOT and the NEUTRAL...

connect the grounding wire to the sheet metal....

and plug the cord into a wall outlet?
at this point only the half circle ground pin will be going into the outlet.

will that work as a ground?

i'm afraid of plugging stuff in the wall hehe.

Rise

email or aim please. ( RisinFire )
nick.hoang@verizon.net
 
Hi RisingFire,

You may be right,
it might be static.

But first,
these items would normally carry adequate earthing facilities.

Check that you have constructed it properly.

If you're satisfied that you have made it right,
and that the metal parts are not earthed,
then this is not a good situation.

Your logic of providing an independant earth to the unit by
using the earth pin from another socket,
shows that you have given this some thought.

What is wrong with using the earth pin of the socket that
the unit uses ?

My guess is that the unit is one of those 'double insulated'
jobs, and the earth pin on its plug is not used.

Maybe its a sealed unit plug and lead, and you can't get
into it to fit a connection, in which case i would say
change the lead and use a three wire normal mains lead,
and use the earth wire to do exactly as you said.

I am assuming you live in England, where there are laws
about earth leakage and so forth, if you're not sure get
someone qualified to check it out. The metal parts should
not form part of the circuitry involved with the equipment,
they should be capable of being connected to ground without
affecting the operation of the equipment at all.

Music equipment that is used in entertainment purposes may
well be subject to more stringent regulations than private
use. You may find that regular inspections are required.
This is not difficult nor usually is it expensive.
Their main concern is safety.
Plugs have to be in good order, cable grips have to be
secure, cables have to be sound, no frayed or damaged bits.
Basically, its pretty much common sense.
Any exposed metal parts have to be adequately earthed.

I dont quite understand where the different wattage
soldering irons feature in this.

What you describe as a separate wire for an earth, would
probably work OK, but it would look pretty bad, use the
earth pin on the plug, that would be much more practical.

Please come back with some more details,

Regards, John
 
as a temporary solution

i have gotten a long wire and drilled it and screwed it into the side of the unit, into the sheet metal.

and i connected the other end of the wire to the screw that holds the faceplate for the wall outlet as a ground.

i live in the US.

the unit this hooks up to, a playstation controller, which hooks into the playstation, does not have a grounded power cord.

so far i think this method of grounding is working.
although yes, its pretty ugly, there's a wire on my floor hanging out of the outlet haha.

if i could modify the power cord that the playstation uses, to change it into one witha ground, that would be nice, but i dont think i can do that.

so i assume, like yous aid, this is a double insulated situation.

i dont believe there are many soultions to this actually

oh i said the part about the soldering irons cause at first i thought i was burning out the circuit boards during soldering.

Nick
 
Hi Nick (RisingFire),

Glad you got something sorted.
Could you perhaps ask around your mates to see
if they have any suggestions?

If you replace the plug on the playstation lead,
then surely that will allow you to use its earth
pin? Even if you have to tape the extra wire along
with the playstation wire, at least you know it cant
be Un-Earthed by accident.

Is it one of those fittings where the wall plug is
also a small power supply built as a big fat plug?

We have those here in England quite a lot, they can
be a pain in situations like this, using accessories.

I am assuming this is private use,
it would never be allowed otherwise.

Regards, John


PS: if it has a transformer type supply,
you may be able to earth the playstation too,
in which case you may be able to put a
three wire mains lead for the whole assembly.

John
 
yeah the plug for the playstation is a big fat plug with only 2 prongs
so i assume its a simple or complex power supply inside

yes this is purely private use.

chances are i dont want to mess with the power supply

BUT, if i do add a 3rd wire
and tape it along side

could i merely attach it to the 3rd prong for grounding in the outlet?
i guess simple soldering would work.

there would be no problems if that 3rd wire was just alone and plugged in right?

like taking apart a power cord, and just taking the prong and attaching my wire to it, meaning i just ground when i need to, as opposed to having a whole new plug.

maybe i can wire something straight into the playstation yeah.
 
Hi Nick (RisingFire),

Yes, i think i see the situation now.
I'm guessing there is a lead from the 'power supply cum plug'
that feeds the playstation, which is not a mains lead in the
usual sense, just a low voltage for the unit, probably with
a smaller plug to plug into the playstation, yes ?

Well, by earthing the parts that you did,
it is my opinion that you effectively earthed one side
of this low voltage feed,
However,
wait to see what other replies you get before doing anything.

I would suggest using the earth pin on the power supply unit,
and running a wire from it to the negative side of the
low voltage supply on the power supply unit.

That would be a fairly short wire, and would do the same
thing as the longer wire that you already tried. If you do
this, dont use both, cos you dont know for sure which way
round the low voltage is, and you dont want to short it.

I dont know if this makes sense to you, get others to read
it too if you arent sure.

I will try to put it another way:
You already earthed one side of the low voltage,
and that was OK.
I'm suggesting you do the same again, but at the
'plug cum power supply' end.
A short wire from the earth pin to the neg side
of the output voltage.

But dont do both, as i said, you dont want to short it.

Also wait and see what others have to say before you do.

Thats about the tidiest way i can see.

Another possibility is a 1k resistor to the earth pin,
mounted inside the power supply unit, to one side of
the output. that should kill any static charge.
If not, then its not static.
That might be more agreeable than an earth wire.

See what others say before you do anything.

Regards, John
 
I don't know what the rules are in the US, but the Australia/New Zealand Wiring Rules, state that any exposed metal, which is earthed, must NOT form part of the circuit. Therefore, you can't connect the earth pin to the low voltage supply, whether directly, or via a resistor.

The safest idea, is like you did earlier - a grounding lead going to a separate plug, with the active (hot) and neutral pins removed. Do yourself a favour, and get a double adaptor - that way, you can plug in your playstation supply and your ground lead next to each other. Then you can tape the ground lead to the power lead.

BTW, in the interest of safety, when you remove the active and neutral pins, don't just cut them off - remove them COMPLETELY.

Actually - on second thoughts - you don't need to remove the pins - just don't connect them to anything :oops:
 
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