What Connection Paste for 3000 Amps Busbar

The material that is stated on the maintenance procedure document in the organisation's quality documentation!

It doesn't exist or if it does, it doesn't say?

Oh dear. However will the business continue to operate when all the knowledge leaves for other jobs <rhetorical question>?

Industry standard for reducing bus-bar joint, contact resistance is silver plating of the contact area. There is no conductive paste, to my limited knowledge, available to industry, for this purpose.

_{It would be nice to know what these busbars are made of...}

chopped up busses, of course!

Just use the good old flour and water paste. When they ask you why, tell them you got the information from me instead of the proper sources inside your company.

We use a generic electrical contact grease on most connections. Connections in corrosive atmospheres and/or critical applications will get silver plated and then greased. The key is regular maintenance. We clean and re-grease most connections every three years. Silver plated connections are refreshed annually.

Good luck

This is not an endorsement but I have seen this product used on high voltage/current equipment:

http://www.sanchem.com/aSpecialE.html

However you still have to properly prepare the surface, use the right fasteners and torque them to manufacturer's specs. As a final step thermal image them periodically to ensure their integrity.

Solder paste.

Vaseline

Conducto Lube from Cool-Amp is the preferred product around here.

http://www.cool-amp.com/

Why are you taking it to pieces in the first place? Is there heating at the joints?

I've had bars running at 4000A continuously for 25 years, other than cleaning off dust they're never touched.

They need to package it in a better container. A lot of silver solder paste has the same problem.

It is many years since I was employed designing and building busbar systems. Back then we specified; clean contact faces with fine emery followed by an acid wash, and then smear them immediately with petroleum jelly to prevent re-oxidisation prior to assembly.(Vaseline is an impure version of PJ) The industry may have moved on to more sophisticated products but some of the plant that I worked on 40 years ago (3-8kA power station GT connections, 10kA electro-plating lines and 2kA 48VDC telephone exchange battery banks) are still operating today. Torquing up the bolts to the correct tightness is equally as important as cleaning and protecting the contact faces. The objective is to exclude any air that is needed for corrosion to form while not tightening so much that the soft bars distort. There are torque tables available on the web or from your local Copper Association. Plating the contact surfaces is generally only used where the contact is intended to be broken and remade during service. The expense is rarely justified for static busbars.

Decide on a standard of acceptability, typically 0.002-0.01Ω per joint and test each joint as it is made. If it falls outside the standard, remake the joint before proceeding with the rest of the installation. If you leave testing to the end and one of the middle joints fails you will disturb the surrounding joints as you remedy the problem.

The answer to your question is a moving target that changes with time and technology. Copper is the preferred bus bur material for stationary applications and aluminum for mobile applications. Copper should be cleaned with Scotchbtight or equivalent and silver plated with Cool amp, brush plating, or electroplating. The bars are then tightly bolted together. If compression stress can be maintained, 100 mesh woven silver screen can be compressed between two busbars. The screen will yield and form a gas tight joint that will last for many years without maintenance.

For aluminum bus bars, careful cleaning as above and addition of an electrical joint compound is best. Burndy makes a synthetic based compound called Penetrox a-13. For applications that don't permit silicones, you can use Penetrox a which is petroleum based.

Hello,

thank you all for your answers. I finally bought Electrical Joint Compound PENE8 from Burndy in the USA. It's exactly the stuff I needed. Surprised that we don't have anything similar in the UK.

Jurgen

As I pointed out it was a long time ago. The company that I wiorked for at the time was a multinational cable maker who owned a subsiduary called BICC Burndy. The company was later bought out and broken up. The name is too much of a coincidence for it not to be linked. Small world.