Turning time into money…

“Time is Money.” It’s a well-worn cliché that sticks around because it’s a cliché that’s true. We’ve heard it so many times that we don’t even think about what it means. So, let’s say it in terms of your submersible water systems business: “A MEGGER IS MONEY.”

Here’s why… The homeowner calls and is “out of water”. Of course, they probably have plenty of water. Something is just keeping them from getting it out of the ground, and it’s your job to find out why, fix it, and most importantly, get compensated for it.

When you arrive, you’re going to take your usual obvious first steps such as verifying they actually have power and so forth. But, beyond that, there’s no better tool, no faster way to figure out what’s going on that with a megohmeter as the next step. Often just called a “megger” or insulation tester, a megohmeter measures insulation resistance. It’s essentially a high-powered ohmmeter. A megger answers the question of, “is the electrical part of our submersible installation isolated (or insulated) from the non-electrical part?” Said another way, “Do I have a ground fault in our system?”

Yes, right now you’re asking, “Why can’t I just use my trusty Simpson 372 ohmmeter for this?” The answer is the amount of electrical pressure, otherwise known as voltage, that each instrument applies to the system. Sure enough, if your system is completely grounded, the ohmmeter will tell you exactly that. Where the megger is invaluable is finding that splice that leaks just little bit, that little nick in the drop cable, and all the other things that aren’t obvious that can lead to a ground fault. Continue reading

Ductile Iron and Franklin Submersible Turbines… not just jargon

Advertising and product literature are full of jargon and buzz words. They are thrown at us with such authority, with such confidence, that we are made to think something must be better because it sounds better. My cell phone has an “advanced Lithium Ion battery”. Must be better… I guess… not sure why.

I thought of this recently while reviewing a literature piece for Franklin Electric’s ST Series of turbine pumps. The discharge brackets, suction brackets, and the bowls are all made from ductile iron. I like the way that sounds, but my bet is that most people in our industry can’t tell you what ductile iron is, or why it’s better. Here’s why it actually is…

As it turns out, ductility refers to the ability of a material to flex without breaking under tensile stress. That is, from stretching, pulling or bending. Ductile is the opposite of malleable, which is a material’s ability to bend and deform without breaking under compressive stress, such as being beat with a hammer.

Ductile iron isn’t just iron, but an alloy. Alloys really took off a few thousand years ago when someone discovered that mixing melted tin with melted copper created a new metal that became known as bronze. This metal had completely different properties than either copper or tin. In this case, it was greater hardness and a superior ability to hold an edge. This turned out to be especially handy in the manufacture of the weaponry of the time. Continue reading

PID: 3 letters made simpler

Hang around any one of our industry trade shows for long, and you’re going to hear the term VFD. Of course, a lot of you are installing VFDs to deliver constant pressure and already know that a VFD is a Variable Frequency Drive.

Hang around or read about VFDs a little longer, especially on the commercial side, and you’re going to see or hear, “our VFD uses a PID controller.” But, as a rule, no tells you what a PID controller actually is, or even what it stands for. That’s probably because PID stands for Proportional, Integral, and Derivative. That right there probably explains why no one goes any further.

But, like many things, it’s not as intimidating as it sounds. A PID controller isn’t a physical device, but a piece of software inside the VFD. PID controllers are used in tons of applications beyond VFDs, and your brain has a pretty good one built right in. You use it for just about everything that requires physical action.

For example, you’re coming up on a stoplight that just went from green to yellow. Without you consciously thinking about it, your brain determines 3 things: How far am I from the light? How long has it been yellow? And, how fast am I approaching it? These get integrated into a decision that results in the correct (hopefully) physical action.

Thinking in terms of a pump now, the job of the PID controller is simple: “How fast should I tell the VFD hardware to run the pump at any given moment?” And, like your brain, it takes the answers to 3 questions (P, I, and D) to come up with the right answer under all the different circumstances and installations.

The proportional part of PID answers the question of, “How far are we off?” That is, “what’s the difference between the target pressure and the actual pressure coming from the sensor?” On one hand, it seems like that’s all we need to know. However, as it turns out, if we only tell the pump how fast to turn based on this question, there’s a tendency to chase and constantly overshoot our target. We no longer have constant pressure. Continue reading

A shortsighted job candidate…

I recently conducted a job interview with a potential Field Service Engineering candidate. Good guy, sharp, professional, just about to graduate with a 4-year Mechanical Engineering degree from a top school. I wanted him on the team. But, it didn’t happen. He left a voice mail this morning telling me he is pursuing other options. He provided a couple of vague reasons, but I think the real reason is something that came out in the interview: He doesn’t think the water systems industry is glamorous or high tech enough.

It’s his decision to make, not mine. And, I can understand why a twenty-something might feel that way. We’re not involved in nanotechnology or finding life on Mars. It’s hard to look at a ½ horsepower control box with its 2 components (relay and capacitor) and think “high tech”.

But, he made a bad decision and has a shortsighted view. Here’s what he didn’t get: There’s nothing else that offers a more interesting intersection of different disciplines than the water systems industry. To be part of our industry is to be involved in electrical engineering (motors, controls, VFDs to name a few), mechanical engineering (pump design, hydraulics, vibration analysis, etc.), materials science, metallurgy, and geology. And that’s just the technical side. To be in our industry is also to be in the middle of a slew of today’s environmental, political, and legal issues. All of it revolving around water, life’s most basic need.

What could be cooler than that?