Grounded to a water pipe picture û requesting comments 1

[MotorGenerator]

Hi – Sorry for the beginner question but I’ve come across this system that is grounded to a water pipe. I’m concerned about the paint and corrosion on the water pipe that could prevent a good electrical connection. I haven’t got into testing the system (other than a simple DMM - couldn't prove a good connection) but I would appreciate any comments on how to ensure this connection is a good one. i.e. scrape the paint and maybe some kind of lubricant????

 

[7anoter4]

I think the upper ring only hold in place the grounding cable and only the lower ring is used for grounding. Some welding points between this ring and the pipe will improve the contact and grounding continuity.

 

[waross]

The upper ring appears to be an approved galvanized malleable iron grounding device. If t was properly installed there is no need to worry about it.
The function of the lug on the end of the cable is not clear what. The angle of the photo does not show enough detail.
I would leave the installation as is.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[squeeky]

Unfortunatley i cannot view the photo. Bonding is common. Ensure you bond everything. I have seen pin holeing due to electrolytic errosion. Because you now have an electrode at one potential and there is another piece of metal at another potential due to stray currents or ground salts, it will act like a galvanizing plant and move metal from one electrode to the other. Bonding and bring EVERTHING to the same potential is the only answer. If you don't do it at first, by the time you get your first holes, its tooooo late.

 

[DRWeig]

I'm going to agree with waross.

Best to you,

Goober Dave

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[busbar]

I would scrap the entire installation and install a single, properly sized, listed ground clamp that has not been field-fabricated or field-modified like the two pictured. The top clamp has “stacked” washers/hex nuts that do not appear to be part of the original assembly, and the lower mess serves no electrical purpose.

 

[waross]

The upper clamp appears to be a type of clamp that is listed for grounding.
See Here:

http://www.tnb.ca/en/catalogues/online/industrial_mro/pdf/c2/blackburn_03_ENG.pdf

It may be a size too large but probably not. Extra long bolts are common with these connectors. There should be a size shown on the clamp. (Raised letters in the cast malleable strap). From the length of the bolt ends I suspect that the nuts and washers were added so that the socket wrench would reach the nut.
The lower figure shows a type of weld-on grounding tab that is common in the petro-chemical industry. I am not sure if this is welded to the strap around the pipe or the pipe itself. If the tab is welded to the pipe this is OK. If the tab is welded to the strap then it is not code compiant and superfluous. Tabs such as that are used to connect grounds to tanks, vessels, pile caps, and structures. Some specs. may require the aluminum alloy connector to be replaced with a silicon bronze Servet post connector.
See here:

http://www.benwin.com.sg/UploadedImg/1157945664_servit post KC,K2C.pdf

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[stevenal]

I'll go with Busbar on this. Extra oversize nuts would violate the listing. Use the right wrench instead of modifying the clamp to fit the wrench.
The tab looks to me to be attached to the strap. The angle iron to the right either extends to and attaches to the wall to provide support for the pipe, or not. If not, the strap and angle iron make up a non-listed grounding assembly. If it's a support, it seems like a bond to prevent a potential difference between the pipe and support might be prudent.