Eddy

[cliffed]

Just found this on another forum… no comments on the actual pic…this can’t be right can it?

 

[James]

So where is the enclosure earthed!!

Top right just out of the picture maybe?

 

[Petej999]

So where is the enclosure earthed!!

How long is a bit of string mate, your guess is as good as mine, but vwe aint talking earthing it's eddy currents we are yapin about

 

[pirate]

I found this video re domestic sized installations quite informative:

 

[Petej999]

So where is the enclosure earthed!!

Dunno Mate not done the training for distance viewing

 

[IAmSparkytus!]

Hello to all,

Rather than start another eddy current thread, thought I'd just tag onto this one.

Cables contained in metal trunking which is bushed to the side of a 12TP dis board. Lives and neutrals go through one 50mm brass Bush into RCBOs. The earths go through another 50mm hole which is in line with the earth bar.

Will the brass bushes prevent eddy currents as the brass isn't magnetic?

 

[littlespark]

The metal trunking and any metal enclosures will be bonded, so any eddy currents will be grounded.

 

[IAmSparkytus!]

Is that correct? I've done some research and never heard anyone mention that yet?

If so, that means there was never an issue to start with which is the best result.

 

[IAmSparkytus!]

No mention of that as a solution in the regs either? Is there any clarification on that?

Thanks!

 

[James]

Eddy currents can circulate in any ferrous metal, grounded or not.

 

[IAmSparkytus!]

Eddy currents can circulate in any ferrous metal, grounded or not.

Back to my post then, will the use of brass bushes prevent them with brass not being ferrous?

 

[nicebutdim]

Back to my post then, will the use of brass bushes prevent them with brass not being ferrous?

Aren't these brass bushes fitted in ferrous material?

 

[Avo Mk8]

Back to my post then, will the use of brass bushes prevent them with brass not being ferrous?

No.
If the whole ferrous plate was replaced by brass, then yes!

I think the 'hole paranoia' about eddy currents in domestic installations is ott!
John Ward did manage to raise the temperature of the bit of metal consumer unit between single cables by a whole 2 degrees after 5 minutes of over 100 Amps

. I don't think we'll be starting many fires this way

 

[James]

Back to my post then, will the use of brass bushes prevent them with brass not being ferrous?

Short answer is no.
although being brass will prevent the bush itself being affected, magnetism will pass straight through and the steel plate will be affected just the same.