To avoid squandering the limited time that maintenance has available, look for maintenance practices that can be eliminated. For example:
• Tighten connections. This practice actually leads to connection failure. And even if connections are tight, how do you know the mating contact surfaces aren’t oxidized? Since you’re in the enclosure anyhow, use a thermographic camera to spot connections that need attention.
• Check supply voltage. If the voltage is so important, it should be continually monitored rather than just checked quarterly. Install a local voltage meter, if nothing else.
• Replace filters. How do you know this wasn’t done just last week as part of a repair? Simply replacing filters per the calendar is often wasteful (if the filters are good) and insufficient (if the filters get dirty soon after changing and stay that way until the next quarterly PM). You can try modifying the filter assembly so the filter medium is easy to see and change, or you can put a D/P (differential pressure) alarm across the filter. Changing filters when they need changing costs less and improves uptime.
