Should you own test equipment or rent it? You could look at this strictly on the basis of total acquisition cost per year. To do that, multiply the days of usage by the daily rental fee. Or if you rent by the week, you would multiply by the weeks of usage.
This math immediately rules out renting digital multimeters (DMMs) if, as is typically the case, every technician uses a DMM every day. This math would probably also rule out buying certain kinds of test equipment that you presently use only a few times a year.
And this math can lead you to make some very expensive decisions.
For example, consider the DMM question. Not all DMMs are the same. Maybe having a specific advanced feature would allow much better troubleshooting on critical equipment that is presenting problems that seem to defy solution. So you save that $50 rental fee by not renting DMMs. How does this stack up against the $25,000 of revenue that’s been lost so far due to this problem?
So, yes, it can make sense to rent DMMs. It can even make sense to rent DMMs identical to the ones you already have. Here are two examples:
- Suppose you have problems with a production line and need DMMs with monitoring functions. You already have those, but if you stick them on this line, your techs won’t have them for their normal work. Same thing applies to monitoring motors, breakers, power quality issues, etc.
- A quality issue or warranty issue comes up. Or maybe it’s a legal compliance issue. This thing’s going to court. You can present test data, but if you don’t take measurements with calibrated instruments and don’t have the proper documentation, the other side’s expert witness is going to tear you up. You don’t have time to send DMMs out for calibration and even if you did, your techs need their DMMs. So you rent calibrated DMMs.
Ah, but the math won’t steer you wrong on that (relatively) big budget thermographic camera. Right? You have an annual outage, and it lasts 10 days. Renting for 10 days makes a lot more sense than buying one that will sit for the other 355 days. And therein lies the reason you probably need to buy. Why is that camera sitting for 355 days?
Consider the fact that you’re going through 355 days without looking at what’s going on with your panel connections, motor bearing temperatures, circuit breakers, fuse connectors, or anything else that conducts current. Many problems become invisible during an outage; you should be looking for them when there’s not an outage.
And what about the building envelope? Those expensive argon gas windows can leak. And when they do, the glass will bend inward and their insulating value will go down dramatically. Your energy savings are literally going out the window. You can see this problem with a thermographic camera. You can use that camera to spot many other issues with heat loss in the winter or heat ingress in the summer.
But there’s another, more important reason to be using that camera all year long rather than just during the outage. Suppose you have friends who golf, and they visit you once a year. That’s the only time all year you ever step onto a golf course. How well do you think you will do?
Thermography is much more than simply pointing a camera. Yes, cameras today are available with all kinds of automatic features. But they don’t automatically take good thermographic images. Nor do they know how to interpret those images.
Think of how autoflash works on a regular photographic camera. That camera takes a light reading, then adjusts the flash accordingly. If your subject is sitting in a chair under an accent light and you just point and click, you’re probably going to get a dark picture and the person won’t even be recognizable. That’s because the camera didn’t adjust to the subject, but to something else nearby.
This same problem arises in thermography. An untrained, unpracticed thermographer can easily get “normal” readings when, in fact, there’s a critical problem that is heading toward catastrophic failure.
If you would not feel comfortable as a passenger on a plane piloted by someone who flew only once a year, you should not feel comfortable giving a tech a thermographic camera only once a year either. Both require frequent practice.
With constant budget pressures, it can be tempting to let a simple calculation guide your decision. Save money by not giving in to that temptation.