Has anyone found a better lubricant that doesn't cause the same issues listed below?

We have a couple hundred ABB K-600 and K-1600 breakers in service within our power station. Our original RCM analysis suggested that a 10 year maintenance frequency was to be implemented. Now that many have gone through a cycle of this we are finding that they are failing due to lubricant drying up and becoming like a glue. Most have been found to operate very slowly, and some not at all. Luckily for the most part the breakers aren't used until the maintenance period, but a few have failed in service creating other problems. We are using the silicone greaseless lubricant suggested by the manufacturer.

What type of breakers are they? Is it electronic or mechanical?

If I remember correctly, there is a good NFPA standard for maintenance of electrical eqpt which mentions the maintenance is about 3 to 4 years a a guide.

However, what sort of maintenance tasks that you perform every 10 years?

Sorry Josh,
I was looking at our maintenance system description when I gave the manufacturer of the breaker.
The breakers were manufactured by ITE. I think this is now part of Siemens. The breakers use a charged spring to trip and close. All have been retrofitted with electronic overloads from Seimens or ABB. The electronic overloads have been relatively trouble free. (The odd failure has occurred, but we just upgrade them when it does.)

For maintenance we do a check of the:
-ductor impedance,
-a check of the contact sequence (Slow close procedure),
-check and adjustment of contact pressures
-contact centering
-check of all contact clearances
-check the latch engagement
-check of trip adjustment
-Ohm check the motor, latch release coil, control coil, and trip coil
- General cleaning, and check of wiring connections, brushes, and rollers
- Megger motor
- Check of electrical operation for the few electrical breakers.
-Check of the electronic overloads for all fault conditions
- Once fully assembled it is checked to ensure that the resistance is infinity between contacts, breaker frame, and ground.

We were initially operating on the 4 year interval for maintenance, but nothing ever went wrong with the equipment. We usually introduced more problems with maintenance than ever occurred on their own. This is when the 10 year maintenance was decided on after an RCM review of the equipment, and operating context. Also our procedure had more final checks to try and catch the problems introduced by maintenance.

Then the silicone grease was found to be an issue.

Thanks for your help Josh.

Sounds like you are confident with the 10 years frequency except that the grease is dried up by then. This makes the grease becomes the limiting factor.

However, I think we have to be careful with all standby equipment such as these breakers. To ensure that they are working when needed, we have to test them periodically. Can or did you somehow test them to make sure they are on good working conditions within the 10 year period?

Prior to doing the maintenance above, did you test the breakers before dimantling to know whether they are working or not, or just go straight to dismantle them?

You mention RCM exercise recommended 10 years maintenance. Which N&H's diagram fits the breaker failure history or they just extend because they were no failures previously?

I'm sure some electrical heavyweights in this forum would like to chip in later on here....

Hello Josh,
I wouldn't necessarily say we are confident. I have moved the maintenance back to 5 years to prevent these failures of operation. This lubrication causing the slow operation is not taken lightly, and it appears that up to 6 years there isn't a problem.

The transfer schemes are checked every two years. (This involves an open and close operation of each breaker to confirm it is functioning.) Before the breaker is removed from service it is operated. This is unfortunately how we began finding that they had failed. Then it also occurred when a transfer scheme failed to operate within the require timelines, and caused a much bigger breaker to become our protection for a small system.

There was an extensive RCM carried out by our former analysts. Unfortunately I was not involved due to my junior status, at the time, within the company. We have very little supporting documentation regarding how the timelines were decided on. This is why I was reviewing this item, and trying to get as much failure information, others experience, and input from people such as yourself to make an educated decision. We will still need to get our RCM committee together together to review, but the more I have to do an analysis the better.

I'm very junior to the RCM process, and I am willing to take any help I can get.

I thought the RCM process & results should be recorded for continous improvement, review, checking, traceability, auditability, etc.

So did we. There is the template, and an accumulated record of failures, but not much in the way of the FMEA, or criticality analysis.

Most of the major systems analyzed do have a better trail, but for some reason this system has limited documentation for future review. This is why I'm trying to build up this material to reanalyze and then move forward with the reviews in the future.