Measuring residual current. How do I know what RCD to fit?

[trev]

very witty Trev.

Those who know my sense of humour will know what I'm getting at. :bucktooth:

Biff! Can I borrow one of your epic fail pics please.

 

[Marvo]

"You can measure the earth leakage by using an earth leakage clamp meter and clamping all the phases (and neutral if there is one) simultaneously."

That is the kind of thing I was looking for, I just can't find one!

You can do this with any earth leakage clamp meter.

http://www.test-meter.co.uk/earth-leakage-clamp-meter/

 

[Des 56]

Breaking news
Fork truck runs over extension lead


"Unfortunately, just one of those things we can't protect against"

I just wish there was some way we could

 

[Inteificio]

You can do this with any earth leakage clamp meter.

That is the obvious thing I was clearly overlooking.
Was just looking at the instructions and clicked.

I will now slowly walk away feeling daft.

 

[mechelec]

If you are being told to fit RCD protection use something like this

Earth Leakage Relays

fit one for each machine on it own dedicated feed (if required) and set to maximum setting (30A) and maximum time delay. You will have fulfilled the instruction you have been given and shouldn't get nuisance tripping.

 

[Inteificio]

I take it #22 is not an option

Thanks for the offer, but I won't design it wrong...probably.

 

[Jaxo]

So if I fit an RCD its ok to wire my factory in extension leads ?

 

[Plonker 3]

Wow lots of questions at once.

Reason for RCDs, many.
For a quick answer.
These will be fed off plugs and sockets, regs indicates RCD requirement.
Boss wants RCDs.
Operators are a f£$^%ing liability and are so reckless with equipment everything in this factory needs RCD protection.
No reason not to add additional safety, if something is designed correctly, it won't cause an issue, but stop an accident.

"and i smell a cascading feeds epic here as well..." - Each piece of equipment will have it's own dedicated feed. Not sure what you meant though, so care to expand?

"What happens when one machine packs up, it takes out another 3 or 4 or whatever? " That's a good thing. If one item on the production line has an electrical fault the production line stops.


Des, I know little about mining, so your references are lost on me.
Basically a packing machine. Main boxer -> conveyor -> metal detector -> conveyor -> weigher -> LS.


RCDs are going in, no choice on that.
I need to know how to design to avoid nuisance trips.

So what does he suggest you do?

 

[Inteificio]

"So if I fit an RCD its ok to wire my factory in extension leads ?"

Clearly not, however if you have to deal with stupid people it means they are less likely to be able to hurt themselves.


"So what does he suggest you do?" - He is a mechanical engineer.

 

[Plonker 3]

"So what does he suggest you do?" - He is a mechanical engineer.

So why is he not listening to your professional opinion?