I am wondering if anyone can give their thoughts on maintaining electronic equipment to help improve reliabiliy for equipment such as Motor drives(VSD), PLCs, process cards, network coms, Photo-electric and laser sensors, proximity switches, ect
The company i work for has a variety of electronic equipment aging from 35 year old analog cards to brand new digital equipment with a large proportion of this equipment averaging 10 to 12 years old. Im wondering how to best implement a maintenace plan for this equipment as in the past we have had costly failures of this equipment which can sometimes be very difficult to fault find. We already have a maintenace program but this is more based on physical inspections and cleaning.
The issue here is that a change out and replace program is very costly changing all electronic equipment every 10 years or so and this in its self wont stop all failures. The cost justification of doing this is very difficult.
So my questions are how do other companies maintain there electronic assets and what type of schedules do they put in place, if any. What is the usual change out life of this type of equipment and how can the cost be easily justified to management. Or is many electronic equipment deemed a run to failiure item with a contingency plan? Your thoughts would be appreciated.

Very important to keep electronic equipment clean, dry, and proper temperature. If there is a vent system and filter, those should be kept in good order.

Periodic vecuuming of dust bunnies with equipment deenergized is not a bad idea.

Infrared thermography is a technology available which in theory might be able to catch some component failures (for example fuse, less likely a capacitor). But imo it's a longshot to be able to find anything on electronic equipment. We have begun performing infrared inspection on a very few critical electronic / control panels at our plant (not my idea).

Periodic replacement strategies may be a good idea, if you have specific knowledge about aging failures to which the equipment is prone (based on manufacturer guidance or plant experience). Needless changeout introduces the infant mortality concern... may be tempered through burn-in of some components.

BlueScopeEddy

I was a systems maintainer in the Navy and part of our system routines was to monitor and trend indicators such as voltage, current, waveforms and the like. Many of the old circuits and some of the newer systems required a 3 to 6 monthly retuning of circuit parameters to ensure that circuits and systems were not being over driven and that wave forms were correct for the system operation. It really depends on what type of circuit, equipment it is, what information you have available on the equipment and whether the operating voltages and waveforms can be monitored. A major obstacle I can see to these methods is that many companies are reluctant to allow their employees to work on live equipment making these type of maintenance actions impossible.

Based on the 6 failure patterns electronic component and parts will either belong to pattern e or f, which means that the likelihood of the failure will always be random in nature.

One of my suggestions would be to have a board repair group in which it would be a good idea if you have a back-up of electronic boards that fail frequently, i think based on your experience you can identify which of these parts frequently fail. Applying a RCA would also be beneficial if we have the same electronic parts that fails on frequently.

Thermography would be of use for electrical and some electronic components but we have a problem on this most specially when you have 10 boards lined up in parallel where you can only scan board no, 1 since the 2nd board is at the back of board no, 2.

Try to place a sticker called thermal paint where you can stick them on motors, heatsinks and those that heats up.

My Warm Regards,

We have faced the same issue in some areas of our plant. If you have several of the same type equipment, you could make a proactive plan to replace one unit and use it for spare parts for the remaining units. Once the experience of replacing a unit is in place, you can better decide which path is best.

Most new units are more efficient than older units so there may be rebates that could help to recoup costs.

We realized that many of our HVAC units run close enough to 60 hz that we would be fine just running across the line.

I've formed the opinion that HVAC motors are more reliable running across the line as they almost never shut down except for maintenance and power outages. VFDs have a higher failure rate than motors and motors running by VFDs have a higher failure rate than those running 24/7 across the line.

It's a tough issue for sure.

Silicon things are unpredictable but we have found that electrolytic condensers that now is 18-20 years as found in PSU´s of most things and in our things of that age by now have dried out and is not working. Replacing those older than 16-17 years seems to be a good idea. Normally things go on working after a replacement. For other silicon failure it´s only to wait and have spares unless spares can´t be found then it´s time to look for replacement. Olov

Yeah, instrumentation seems to cause a large portion of the trips. Do you test your control and trip loops frequently online or offline, using the MOS (Maintenance Overrride Switch)?

There is a US MIL standard for electronic eqpt reliability (about 1000 pages) which you can get from internet. Maybe you can read it to get some ideas.

There is also a good NFPA standard for maintenance of electrical equipment.