I have 50 separate LED lights plugged into UK AC230v Sockets, each LED has its own driver, they are fixed onto metal framework which is also supporting draws and shelfs.

Everytime I open a draw or touch a shelf, I get a light electric shock, not painful but does produce a cracking sound.

Is this a cause for concern?

If you had to guess from experience, what would you say is the most likely cause of this, Also, would there be a straight forward way to diagnose?

It would be a very tedious and time consuming process to manually test every LED and its driver.

 

? static ?
try adding an earth to the metal cover,
that will either cure the problem if its static or blow a fuse / circuit

 

Is the shock just a short time or does it continue as long as you are touching the metal?

 

If its a periodic "Zapp" most likely static charge.
If it persists end occurs just about every time you touch it, could be mains power leakage.
Either way, if you earth GND the metal framework, it should take care of things.

 

? static ?
try adding an earth to the metal cover,
that will either cure the problem if its static or blow a fuse / circuit

Ok il try this.

Is the shock just a short time or does it continue as long as you are touching the metal?

quick zap, but occurs almost every time the frame or part of it gets touched

If its a periodic "Zapp" most likely static charge.
If it persists end occurs just about every time you touch it, could be mains power leakage.
Either way, if you earth GND the metal framework, it should take care of things.

It sounds like a mains leakage, because it does occur every time.

Does it imply which part of the AC mains the leak could be? IE ground not functioning properly, or the live wire, etc?


Also, is there a way to confirm its mains leakage with a multimeter or some other way?

 

If its a periodic "Zapp" most likely static charge.
If it persists end occurs just about every time you touch it, could be mains power leakage.
Either way, if you earth GND the metal framework, it should take care of things.

Also, if it is a mains power leakage, wouldnt it be better to locate the leak as opposed to just earning the framework?
Or is earthing the frame and leaving it there considered good enough?

 

Also, is there a way to confirm its mains leakage with a multimeter or some other way?

One, measure with high impedance volt meter to ground, you may see a fairly significant AC voltage, if so, connect a 10k resistor from frame to GND and measure again, if it collapses, does not indicate significant AC leakage, if voltage remains, definitely connect the frame to earth GND.

 

Disconnect the power from your LEDs and see if it goes away. But a mains leakage should give you a continuous shock, not a short zap.

Ir is possible that a DC source of 60V or more is charging the shelving unit as a capacitor and the shock comes from discharging it through you.

Edited: that would show as a DC voltage to ground.

 

Also, if it is a mains power leakage, wouldnt it be better to locate the leak as opposed to just earning the framework?
Or is earthing the frame and leaving it there considered good enough?

Some ungrounded systems do have some 'natural' leakage, often not dangerous, but earth grounding should eliminate it.

 

+1 above.

Even if it's 'safe' now, with low leakage, that could change at any time.

https://www.benderinc.com/know-how/...ounded-systems-as-reflected-in-the-standards/

"the unearthed power supply system". "Unearthed" in this context only refers to the connection between all active conductors and the earthing system.
In accordance with IEC 60364-4-41:2017-03, 411.3.1.1 "Protective earthing", the exposed-conductive-parts must be connected to a protective conductor, depending on the type of earth connection.

 

It could be a good idea to try a mains tester screwdriver like the in the photo below....

 

Does it have a 2-core or 3-core mains lead?

 

Also, if it is a mains power leakage, wouldnt it be better to locate the leak as opposed to just earning the framework?
Or is earthing the frame and leaving it there considered good enough?

First up is safety,
no matter what the source is , exposed metal should be earthed,
this will "cure" static and if its more than that , it will protect you and identify the source

 

Everytime I open a draw or touch a shelf, I get a light electric shock, not painful but does produce a cracking sound.

It definitely is HV (tens kV) spark discharge of static electricity.
230 V will kill without spark and sound, because of relative low voltage.
Human is carrier of static charge, which generates by dynamic interacting shoes and floor surface.
For this discharge does not matter, shelf is grounded or does not.
I never ground my shelf, to prevent deadly case, when one my hand is contacting with shelf,
and I accidentally touch hot wire by other hand.

 

Connecting the frame to a solid "safety ground" is indeed the way to go, if it is a mains voltage leakage. And probably the reason "the shock is not to bad" is because you are not making a good enough connection to it. So when some day you do make a good connection, if you are very fortunate, it will throw you on the ground.

 

Can someone explain to me how one can get a quick zap from AC leakage? In my experience, shocks from AC leakage are continuous.

 

Can someone explain to me how one can get a quick zap from AC leakage? In my experience, shocks from AC leakage are continuous.

Just an idea. . .
When there is a class-II switched-mode power supply the suppression capacitor (generally 2.2nF Class-Y) will be connected from rectified mains negative to output 0V.
There is generally about half mains voltage on the PSU 0V, at a very high impedance.
I wonder if the Class-Y capacitor in combination with the mains rectifier can act as a charge pump is there is a lot of external capacitance.

 

Can someone explain to me how one can get a quick zap from AC leakage? In my experience, shocks from AC leakage are continuous.

Thats a good question
as to what it is caused by
but at least the metal will now be earthed and safe.
My bet is its actually the person that is getting a charge and discharges to the metalwork,
but with an exposed metal work thats not earthed , I think the important point is getting the metalwork earthed.

 

Of course, if the cause of the charge was static in nature, grounding the frame will only enhance the degree of 'zap' received. as the source of the charge originates from the person him/her self ,

 

Of course, if the cause of the charge was static in nature, grounding the frame will only enhance the degree of 'zap' received. as the source of the charge originates from the person him/her self ,

Exactly!

The charge pump idea is interesting. I had suggested earlier that shelves could be charging up as a capacitor.

I say ground it. That will at least give us more info.