The answer to this question appears at the end of this newsletter.


Wringing Revenue from Repairs
Are you leaving free money on the table? Competent production managers know the cost of each minute of downtime on each piece of major equipment. Usually, lost revenue is the primary driver of that cost. Ask your production managers which equipment incurs the highest downtime costs. Focus on speeding up repair time on that equipment, making sure you tap a valuable resource: the manufacturer.

Manufacturers often provide downtime-reducing products. For example:

• Assemblies. Rather than dismantle assemblies to replace a component, you can pop out the old assembly and pop in the new one. If an assembly isn’t presently offered, discuss this with the manufacturer.
• Special components. See if a particular part now has an improved version, such as “rough service” or “quick change.” Or, perhaps there’s a version more applicable to your application. If these aren’t offered, discuss your problem with the manufacturer to see what’s feasible.
• Special tools. Race car mechanics have special tools you don’t find at any hardware store, and so should you. Manufacturers of industrial equipment often have special jigs, fixtures, removers, installers, and other tools that save time. If such items don’t exist, contact a reputable machinist to observe a repair in progress and propose such items. You may recoup the cost of fabrication in the next downtime event.

If that outage is a ways off, visually check for bonding jumpers between all metallic objects in your transformer pens. A driven rod isn’t a bonding jumper. You want to ensure the bonding is per 250 Part V, and the grounding is per 250 Part VI and VII [450.10].


Safety
Who should reset or replace overcurrent protection devices (OCPDs)? It may seem harmless to let operators reset the breaker and call maintenance only if it trips again or won’t reset. However, it’s not harmless. First of all, operators aren’t trained in operation of an OCPD or disconnect. They invariably stand in the blast path — without PPE.

If that OCPD has tripped due to a fault and the fault is still present, anyone operating that OCPD is probably going to be severely injured. Only a person who is qualified to test for faults and then clear those faults should reset or replace an OCPD.


Quiz Answer
Answer to Electrical Troubleshooting Quiz
Operators are not “qualified personnel” to work on OCPDs — this includes resetting breakers. What the superintendent really wants is uptime. To provide that, you need to determine the cause of the downtime rather than be complicit in a practice that is both unsafe and illegal.

Are those fuses sized for the largest load plus? If not, then recalculate for the correct size. This alone may not solve the problem. Closely scrutinize the operation itself. Are the operators overloading that mixer before starting it? Because the problem occurs when starting the mixer, the solution may be as simple as starting the mixer with less material (or before adding material). Monitor the current draw of the mixer under various loading scenarios before reaching any conclusions.