tray bonding

[High Tower]

This thread had me concerned as we do not bond bolted joints the only thing we do do is bond between multiple level trays

 

[Tesla1980]

It's a wonder they didn't make you take the pigtails out. Bad practice.

Can't see the point of earth links on a bolted joint.

It's what they wanted and what I was was told to do it was not between bolted joint there would be no point in doing it then would there it was between mulitple levels of tray ? but thanks for your input

 

[High Tower]

It's what they wanted and what I was was told to do it was not between bolted joint there would be no point in doing it then would there it was between mulitple levels of tray ? but thanks for your input

In fairness I thought the same as tony!

 

[Spoon]

Just been sent a couple of electrical test reports from our trunking/cable tray supplier. Here are the conclusions:

Trunking Conclusion:
All samples tested passed the electrical tests.
A representative sample of trunking was tested to demonstrate that earth straps in copper, tinned copper or none do not make a measurable difference to the impedance of conventional bolted links and snail (punched thread form) fasteners.

Cable Tray Conclusion:
All samples tested passed the electrical tests.
A representative sample of tray sizes and gauges was tested to demonstrate that earth straps in copper do not make a measurable difference to the impedance of both spring clips and conventional bolted links.

 

[johnboy6083]

I feel vindicated!
to be honest, we couldn't of expected any different, it's very basic electrical theory!

 

[Guest112]

I never see the point in fitting the earth links either, but in my experience most jobs ask for it,

waste of time and money by the looks of it

 

[benji]

I think earth links on trunking goes back to when most trunking was supplied painted

 

[johnboy6083]

I think it comes down to common sense. Unfortunately an awful lot of sparks I've seen on site seem to lack it.

 

[grantr37]

Nothing wrong with putting power and data cables in the same trunking as long as it has multi-compartments.
We get ours from TOTAL CABLE MANAGEMENT SOLUTIONS - specialists in trunking, cable tray and ladder: Unitrunk

thanks for that I never heard of this company before...might be better than the various wholesalers ....

 

[Knobhead]

I think earth links on trunking goes back to when most trunking was supplied painted

They never provided links when I was using miles of GE Power Centre trunking.

 

[Spoon]

thanks for that I never heard of this company before...might be better than the various wholesalers ....

We used to use Legrand, but they are too expensive and Unitrunk are very good and same quality as Legrand. Been using them for a few years now.

 

[Engineer54]

Why wouldn't you use earth straps when they are supplied with the tray and trunking?? Before they started supplying earth straps, all our metallic containment systems (apart from conduit) in the factories I did my training in had to have a strap between joints etc. Every project i've ever worked on, call for them!! I'll stick to what i know and have done for over 40+ years, ....the straps go in!! lol!!

I can't ever remember using painted Tray Or trunking, it was always Galvanised stuff i've ever used. I take it your referring to the grey trunking, (can't remember try being painted) often used in office buildings etc??...

 

[Spoon]

I know where you are coming from Eng54. I have always listed earth lugs with the galvanised trunking and cable tray, but these reports say that it doesn't make a difference if they are fitted or not, and in this day and age where we have to save as much money as possible, then I cant see the need to list them any more. Saving on purchasing cost and also installation costs (time used up fitting them)

 

[High Tower]

I really fail to see how any earth link would make a difference to a properly bolted joint.

I just had to install 120m of 125mm tray 2 level with numerous changes of direction and intersections.

25m of 4" trunking again with various changes of direction.

Supply and install with a budget of £2250 I'd love to see anyone fit in bonding joints into that budget.

 

[Knobhead]

Why wouldn't you use earth straps when they are supplied with the tray and trunking?? Before they started supplying earth straps, all our metallic containment systems (apart from conduit) in the factories I did my training in had to have a strap between joints etc. Every project i've ever worked on, call for them!! I'll stick to what i know and have done for over 40+ years, ....the straps go in!! lol!!

I can't ever remember using painted Tray Or trunking, it was always Galvanised stuff i've ever used. I take it your referring to the grey trunking, (can't remember try being painted) often used in office buildings etc??...

I never used anything but powder coated GE Power Centre trunking. It was the standard for our company. One contracting company was told to take out some galvanised that they put in as it looked an eyesore when run between panels that were all our "standard" colour.