Serrated washers on steel conduit

[drzsta]

Never used them in any conduit system. Why would a competently installed conduit run with threaded fittings require serated washers for earth continuity?

Anything painted I rather get good contact with an earth prep tool like G&j Hall manufacture.

 

[7029 dave]

Never used them in any conduit system. Why would a competently installed conduit run with threaded fittings require serated washers for earth continuity?

Same, folk can't be arsed today to spend a bit of time cleaning the accessory up to obtain good continuity.

 

[westward10]

As I said in #4 a well installed system shouldn't need them but I still like them.

 

[Marvo]

Okay, what the hell is a serrated washer.?

They're known as star washers in this neck of the woods. Generally used to provide a mechanical lock for a nut especially in a vibration environment. Do they actually do anything to improve earth impedance on steel conduit systems? I've never seen them specified to improve the impedance of a joint, my initial thoughts would be that they may even decrease the contact area or maybe could strip the galvanising off one of the surfaces and accelerate corrosion so could even be detrimental... (**tin hat on**)

 

[Des 56]

Just googled it, and can say don't see the connection with conduit work or any kind. Never used them in my day.

Here,here
Not only have I never seen or heard of washers (serrated or otherwise) being used on a conduit system,the action of introducing two extra surfaces to retain continuity (where no action should be required) seems to be making the continuity and effectiveness of passing a high current worse.
If it was the case it is a better practice why were we not doing so decades since

 

[Rocboni]

If it was the case it is a better practice why were we not doing so decades since

I thought that we were. My understanding that in England the method was different in Scotland, so I'd be interested hearing from Scottish members.

 

[Bobster]

I've always used flanged couplers that incorporate a lead washer for when I used to install conduit systems. Although that was also a requisite for the M&Q regs I was working to at the time.

 

[Pete999]

All right I know I'm going to get some sheet over this, to answer a question someone posed the reason why they didn't use these things years ago was/is because installation standards have gone by the wayside, how many sparkys clean the ends of couplers when used as an end to be fitted into an accessory? how may file the lock nut? how many clean the paint from an accessory box? go figure.

 

[Des 56]

I thought that we were. My understanding that in England the method was different in Scotland, so I'd be interested hearing from Scottish members.

Wales is my experience, but I would have thought the whole of the UK was more unified back then,especially trade practices concerning serrated washers

 

[Rocboni]

Looks like I don't really have an argument.

 

[streamer]

Where did you go to College Rocboni? I'm from the same area as you and I'm sure we were taught to use them at college. Also, it was standard practice when I worked for a large contractor in Glasgow. As was lock rings behind couplers, which you don't always see.

 

[Rocboni]

Scottish Borders.

 

[streamer]

Scottish Borders.

Me too. Although it was the old one up the hill about 20 years ago.

 

[Rocboni]

You'll have been taught by Kenny Redpath then?

 

[streamer]

Yes, is he still on the go? He must be a fair age now.