Laser Machine Grounding/Earthing

[Want2build1]

Hi
My machine has the earth linked out to a connector on the panel.
The manual and video make a big fuss about grounding .
Basically thay want you to make your own earth point with a metal stake into the ground and use it to ground the machine.

1st of all, I'm asking "WHY?"

some thoughts also... it is looped to the mains wiring earth, so the new earth point will effectively be grounding the whole workshop and house wiring !

Could this cause any problems elsewhere on the ring supply ?

I haven't connected mine up yet.

For those old enough to remember .. it reminds me of going outside to pour a bucket of water on the earth stake, when the ground got dry, and the tv picture got smaller ! lol

[longy]

Found this Laser Machine MaintenanceLaser power and the machine body must have good grounded power connection. The earth wire should be connected between the power transformer and the machine grounding connection.
A good grounded connection is great for the following reasons:
A good grounded connection will assure the laser power to work normally
A good grounded connection can extend the life of laser tube
A good grounded connection will prevent any other electrical interference which can impact the outcome.
A good grounded connection will prevent any electrical damage to the machine.
Please make sure to ground the machine properly!

Also I would think that a large amount of static would build up when cutting plastics if the laser was not grounded. Watering the earth stake that's something I've never heard of, besides most household earths have been on PME for the last 30 + years.

[Want2build1]

link here => Untitled

it seems it isn't straight forward, so I will do some more research !

I will make an earth point at the work shop and see if there is a PD between the supplied earth, and my local earth.
Obviously, if there is a PD, then a current will flow !

20yrs ago, when I bought my 1st house, the bathroom, when damp, (after a shower etc.) whould have an earthing problem. if you stood at the sink, and touched the tap, you would get a tingling feeling.. I measured the tap voltage at 50v with the damp floor. I contacted the leccy board who told me earthing was the housholders responsibly ! ... so I bonded the pipes and made a ground earth and all was good :)

My current house is 200 yrs old, and TBH I haven't considered the earthing untill now !
It definately hasn't been re-wires for a long time.
I'd have done it myself by now, but 'we' aren't allowed to any more :(
(yes, I'd have read the current regs and done it properly )

[Want2build1]

The machine IS earthed at the plug socket.

Would it be ok to earth it/the workshop locally too ?

From my audio/on stage days, earth loops can cause lots of problems too !

[Web Goblin]

You can do you own wiring if your considered to be competent but you cant do it for anyone else. Although the exact explanation of competent is a bit vague.
As for your workshop wiring this can require a bit of "expert knowledge" shall we say. Is the workshop part of the house or attached to it or is it seperate from it? Do you know what type of earthing arrangement your house supply has? Most of the time the recommendation is for your workshop to have its own earth, ie make the workshop a TT type arrangement which is the earth rod in the ground.

[Want2build1]

At the moment I have TN-S into the house.
Armoured cable off it's own box from the house to the workshop.
Workshop is about 50m from the house.
Workshop takes the Earth from the house cable. (like TN-S)

To make the work shop TT, I would lift the incoming earth and replace with an earth rod .
Is that what you are suggesting ?

Still, the question is .. does the machine need it's ground connector wiring up, if it has ground/earth through the plug socket (which is linked to the ground connector on the machine panel) To me, it seems redundant ?

I can only assume, that the Laser Machine manufacturers are covering themselves for installations that don't have an earth circuit / system, either because of country or location ?

[Robin Hewitt]

Anyone who believes a word of this rant will be in immediate risk of death through electrocution. You have been warned.
You are up against the Elf'n'Safety fruitcakes here. Originally there were no regulations and working people accidentally sawing through cables electrocuted themselves. Then industry was compelled to put every live conductor either out of reach or inside a steel conduit. Then they decided there should be domestic regulation and they hit a big snag, steel conduit was not credible.
If you compel someone to earth their electric cooker you might simply be providing a return path for the electricity thus completing the circuit and killing someone. A poor ground connection can save your life. So they floundered about then settled for the 25mA residual current breaker (RCB). You really want one of these in the circuit so let's not start sinking earth spikes.
The RCB is a sort of transformer, there are a couple of windings to take the current out to the cooker, a couple of windings to bring it back. These two windings go in opposite directions so they should cancel each other out. If they don't cancel each other out it is assumed that some of the current is leaking to ground, possibly through you, and the breaker opens the circuit to save your life. Test showed it took more than 25mA to off you hence the leakage limit.
Let's now consider the poor unfortunate making the laser who has to try and be CE compliant. ie: it mustn't interfere with your telly. You might think that putting it close to the telly would reveal all, but of course the standard is for telly's of yesteryear which used to be analogue. When things get CE tested for emissions they usually fail because testing is expensive and the tester can make more money if you flunk. So what they do is bung on the CE sticker, add the occasional ferrite to the power lines and waffle on about earth connections in the manual.
This is what you are reading and getting worried about. What you really need is a bit of info about Faraday cages, earth loops and how to get data lines into/out of a cage. Anywhere the 25000V laser PSU might leak wants to be within 1" of the earthed case and your fingers must not be closer than that when it is switched on. /rant

[Web Goblin]

Yes you can install an earth rod for your workshop distribution board. Keep your wire armour but remove its earth connection at your workshop distribution board end only. This way your workshop now has a TT instal and your cable feeding it still has earth fault protection from its supply end at the house.
As for the ground connection for the laser then I would go by the manufacturers instructions.

[Want2build1]

Thanks WG

And as this is "The Internet" so it must be true :) , can I ask your experience with electrics ?

Always best to check !



EDIT ! :> Just checked your profile :) .. as you were !

BTW.. what style Karate do you do ? Grade ?
I got to 1st dan Shotokan before my back/joints stopped me doing more :(

Ta ;)

[Web Goblin]

Odd connection type. Is it a banana plug/crimp type connector?