How about greasing electrical connectors?

[spokewrench]

I replaced the controller on my Aventon Abound. Generally, I find e-bike connectors difficult to disconnect, and this was especially bad. Vaguely I remembered a tool. Later I remembered what it was: my hose removal pliers. Using them might require me to put some sort of hose clamp on each half of a connection for the pliers to pry against. Besides, putting connectors together can also be difficult.

Decades ago, I learned that corrosion on car battery terminals usually comes from acid fumes seeping out around the terminals. A little silicone grease around the posts kept a battery clean and neat. I was careful not to get grease on the post because that was supposed to cause resistance. Then I read an article by a highly experienced electrical engineer who said silicone grease won't cause resistance in connectors because the sliding metal parts will push it out of the way. When he worked for RCA, they even used it on the contacts of television tuners. After that, I greased battery posts liberally. No problem.

Spark plug connectors have long boots so that when you try to start on a foggy morning, your spark won't escape along the wet porcelain. I had success using Permatex silicone dielectric grease on plugs, to increase the moisture rejection and make boots easier to remove.

I have used silicone grease on e-bike connectors, primarily so I can make and break connections a little better, and also to help keep them weather tight. There's still plenty of friction. Is it a good idea?

 

[Base]

We used to subscribe this silicone to hirose connectors. I still use it on other connectors and works fine.

had to dig deep in the memory, I think it was called Dynatex

 

[spokewrench]

Come to think of it, I have a pound of Deoxit Marine Grease, made for electrical connections.

 

[stompandgo]

The best is dielectric grease. It's an insulator, but electrically, it's not. You can get it at any decent auto parts store.

 

[Gionnirocket]

You should not put dielectric grease on the electrical conducting mating part of electrical connections. Though as mentioned it can be pushed out of the way by the mating, it's still not the recommended manner of application. Especially true if the connection mating will be cycled.
The proper application is to the sealing rubber connection covers or over the exposed metal contacts after they are mated.
I received the same advice from an engineer at Boesheild.

Google provided this widely accepted explanation.

Dielectric grease, also known as tune-up grease, is a non-conductive, silicone-based grease used to protect electrical connections from corrosion and moisture. It's not intended to conduct electricity but rather to create a protective barrier. To use it, apply a thin layer to the outside of the connection, ensuring it's applied after the connection is made. Avoid putting it between the mating surfaces of the connection, as this can hinder electrical conductivity.

Here's a more detailed explanation:
What it is: Dielectric grease is a silicone-based, non-conductive substance that repels moisture and prevents corrosion on electrical connections. It's not meant to conduct electricity or improve conductivity, but rather to create a barrier against the elements.

How to apply it:

• Make the connection first:
  Ensure the electrical connection is properly made before applying the grease.
  
  
• • Apply to the exterior:
    Apply a thin, even layer of dielectric grease to the outside of the connection, like around the terminals or the base of the connector.
  • Avoid between mating surfaces:
    Don't apply dielectric grease between the actual contact points of the connection, as this can interfere with the electrical flow.
  • Use sparingly:
    A little dielectric grease goes a long way. Avoid using too much, as it can attract dirt and debris.

And from one manufacturer...

Dielectric Grease on Spark Plugs

Dielectric grease is a simple compound of oil and silica filler that’s very hydrophobic and is excellent at sealing out moisture and preventing corrosion. The trick with using a dielectric grease is knowing where to apply it to seal the electrical contacts from moisture ingress and prevent...

mgchemicals.com

 

[stompandgo]

I've been using it for decades. Always in moderation, as a lubricant, not a sealant.

 

[Gionnirocket]

I've been using it for decades. Always in moderation, as a lubricant, not a sealant.

I put that s*it on everything!
Great as a lubricant, sealant and as described above.
I buy food grade so I can use the same on my aquarium and plumbing O_rings etc....

Amazon.com: Haynes Silicone Grease, Food Grade Sanitary Lubricant, Machine Lube, Prevent Valves and O-Rings from Sticking, 1-4oz Tube Silicone Grease HAYSG 4OZ Tube Clear, 4-oz : Industrial & Scientific

Amazon.com: Haynes Silicone Grease, Food Grade Sanitary Lubricant, Machine Lube, Prevent Valves and O-Rings from Sticking, 1-4oz Tube Silicone Grease HAYSG 4OZ Tube Clear, 4-oz : Industrial & Scientific

www.amazon.com

 

[stompandgo]

You're correct that it is mainly an insulator at e-buke voltages, not so at high voltages. A properly fitting connector will scrape all but a very thin film off, which protects the connector from moisture.

 

[Gionnirocket]

You're correct that it is mainly an insulator at e-buke voltages, not so at high voltages. A properly fitting connector will scrape all but a very thin film off, which protects the connector from moisture.

True... But at best with new connections that will be mated once and done.
Also keep in mind that higher voltage and/or current are more prone to arching and that's why you should avoid all "contaminants"
And with sensitive low voltage/current you can actually increase the required low impedance
It's not serving any purpose between conductors and when applied around and over its sealing out any moisture that can get between the connection.
I realize that there's two rational here.. but following the accepted best practice has never let me down.

 

[spokewrench]

Google provided this widely accepted explanation.

I, too, accepted it. After all, the typical resistance of silicone dielectric grease is about 3x10^16 ohms times the thickness in cm divided by the area in cm^2. How could a film be so thin that resistance wouldn't matter? Yet the electrical engineer said that at RCA they would put it on the contacts of TV tuners to prevent oxidation. (A VHF tuner would have three disks with 12 contacts each, for 2 RF filters and a local oscillator.) If the grease prevented oxidation, a film must have remained.

Okay, I thought. Maybe 10 milliohms wouldn't matter in a tuner, but on a car battery terminal cranking an engine with 100 amps, it would drop a volt. Dropping a volt at each terminal would mean 2 volts less cranking voltage. I had a gadget that recorded cranking voltage. I cranked with posts and terminals clean and dry. Then I took the terminals off, smeared posts with silicone grease, put the terminals back on, and cranked again. The voltage was the same!

 

[fooferdoggie]

this works great for the job. I have used it to waterpoof my garage door opener so I can have it on my bike in the rain.

ACF-50 Anti-Corrosion Lubricant Compound - 13 oz Aerosol - MUST SHIP GROUND!: Industrial Lubricants: Amazon.com: Industrial & Scientific

ACF-50 Anti-Corrosion Lubricant Compound - 13 oz Aerosol - MUST SHIP GROUND!: Industrial Lubricants: Amazon.com: Industrial & Scientific

www.amazon.com

 

[Gionnirocket]

I, too, accepted it. After all, the typical resistance of silicone dielectric grease is about 3x10^16 ohms times the thickness in cm divided by the area in cm^2. How could a film be so thin that resistance wouldn't matter? Yet the electrical engineer said that at RCA they would put it on the contacts of TV tuners to prevent oxidation. (A VHF tuner would have three disks with 12 contacts each, for 2 RF filters and a local oscillator.) If the grease prevented oxidation, a film must have remained.

Okay, I thought. Maybe 10 milliohms wouldn't matter in a tuner, but on a car battery terminal cranking an engine with 100 amps, it would drop a volt. Dropping a volt at each terminal would mean 2 volts less cranking voltage. I had a gadget that recorded cranking voltage. I cranked with posts and terminals clean and dry. Then I took the terminals off, smeared posts with silicone grease, put the terminals back on, and cranked again. The voltage was the same!

I understand that it can be ok... But it's not guaranteed not to be a problem in all cases or in the future.
Best practice is just that... Just because something works doesn't mean it's correct to do so.
I rarely torque anything to spec other than handlebar/stem and never have a problem. But I'm not going to argue that it's better than to torque to spec.
ymmv

 

[spokewrench]

I understand that it can be ok... But it's not guaranteed not to be a problem in all cases or in the future.
Best practice is just that... Just because something works doesn't mean it's correct to do so.
I rarely torque anything to spec other than handlebar/stem and never have a problem. But I'm not going to argue that it's better than to torque to spec.
ymmv

Not me... I didn't understand how it could be okay. I double checked it with my incandescent lights, which drew 13 battery amps. Clean and dry, I think the drop from post to cable terminal on each side was maybe 2 mv. With silicone grease, it was the same.

When my Nissan was maybe 30 years old, the turn signals became intermittent. The switch was lubed with what looked like white grease, which had hardened. I cleaned it with WD-40, put in white grease for wheel bearings, and it worked fine.

At the same time, Nyogel has 758G conductive grease for use in ball bearings of computer equipment, photocopiers, and treadmills, to drain off static electricity. Hmmm.... 10 million ohms may prevent static buildup, while my turn signal switch, lubed with ordinary grease, must have had less than 1 ohm.

Aha! It's like static vs kinetic friction. You slip on wet stairs and tumble down to someone standing on those wet stairs with the same kind of shoes, and he doesn't budge. You'd slipped on a film of water, while the shoes of the stationary person were contacting the steps. Likewise, the viscosity of the fresh grease in my switch was thin enough to allow metal-to metal contact, microscopically. Grease can prevent metal-to-metal contact when ball bearings are in motion.

I guess dielectric grease wouldn't impair the contacts in my connectors, but I have no reason to lube pins and holes. I just want to make the plastic and rubber slide better.