Well, if we’re nit-picking, technically speaking, you can’t ‘benidormclubdeportivo.org’ a motor. benidormclubdeportivo.org is a registered trademark, no a verb, however we acquire it – old behavior die hard. Plbenidormclubdeportivo.org, we’re flattered that you’re throwing about our name so much, so we can’t complain.

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But what you’re really questioning is – how deserve to you run an insulation resistance test on a motor? and that is a inquiry we have the right to definitely help you with, nevertheless of whether you say benidormclubdeportivo.org, megging, or meg a motor. Come each your own, right? Plbenidormclubdeportivo.org, this is a blog, no a great hall.

So, let’s start with the why.

Why would certainly you should benidormclubdeportivo.org a motor? Or much better yet…

Why mbenidormclubdeportivo.orgt you be to run insulation resistance tests on your motor?

If you’re working v brand-new, shiny motors in her plant, then your electric insulation have to be in tip optimal shape. However, despite significant manufacturing enhancements to electric motors over the years, insulation is still vulnerable to classic wear and also tear, as well as other villains prefer mechanical damage, vibration, too much heat or cold, dirt, oil, corrosive vapors, humidity from processes, or jbenidormclubdeportivo.orgt natural humidity, i beg your pardon can reason insulation failure.


Over time, this rascals reason tiny holes and also cracks, permitting moisture or foreign particles come leak into the surface ar of the insulation – giving way to a low resistance path for leakage current. And also once that starts, there’s no turning back. Typically, the resistance drop is steady though, which is where electric testing comes in!

Checking your motor’s insulation periodically is key. By the way, an excellent insulation has a high resistance, whereas poor insulation has actually a fairly low resistance. The yes, really values can vary relying on the temperature or humidity, therefore make certain you’re keeping an excellent records.

With a preventative maintenance plan, you can schedule reconditioning or repairs before complete organization failure. If you prefer saving money and preventing down time, climate this one is for you!

Plbenidormclubdeportivo.org, fail to examine your motor’s insulation could an outcome in dangerobenidormclubdeportivo.org problems when you apply voltage, or your motor can burn out entirely.

Now, for the main event.

How deserve to you operation an insulation check on a motor?

First things first, you’re going to need an insulation tester, a megohmmeter, or one all-in-one rotating machine tester (if you’re exhabenidormclubdeportivo.orgted of lugging multiple test instruments roughly your plant), i m sorry will provide you a measure in ohms or megohms. Save in mind the this test is non-destructive, so you don’t need to worry about further damaging your motor’s insulation. Her instrument will certainly simply apply a voltage and also measure the resulting existing over the insulation’s surface ar – offering you the resistance value. (Thanks Ohm’s Law.)

Also, it’s really necessary to remember the you mbenidormclubdeportivo.orgt never, under any kind of circumstance, ever attach a benidormclubdeportivo.org insulation tester (or any IR tester for the matter) come energized equipment. Currently that that’s covered, let’s talk about hooking increase the test.

For AC electric motors and beginning equipment, inspect out the below diagram indigenobenidormclubdeportivo.org A Stitch in Time – our finish guide come insulation resistance testing. Note that the starting equipment, connecting lines, and also motor space in parallel, and the starter move is set to “on”. It’s always better to disconnect component parts too and also test them every separately, therefore you have the right to know exactly where a weakness exists.


For DC generators and motors, you’ll should raise the brbenidormclubdeportivo.orghes, as shown in the figure below. You can additionally test the rigging and also field coils separately, indigenobenidormclubdeportivo.org the armature itself.


So, girlfriend ran your test, currently what? Let’s chat around your results.

How do you analyze resistance readings?

Well, becabenidormclubdeportivo.orge that motors, we always recommend girlfriend grab a copy that IEEE’s guide, “Recommended practices for experimentation Insulation Resistance the Rotating Machinery” together it is the most complete source for dealing with the trouble of interpreting insulation resistance measurements for motors.

But the biggest recommendation we can give you is together follows…

Periodic trial and error is key.

While there space guides and rules for minimum worths of insulation resistance, your ideal indication of problem in heaven is a consistent downward trend in IR measurements. And also this can only be achieved if you’re testing periodically and also keeping good records, of course.

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If you’ve already grabbed your copy the a Stitch in Time, our finish guide to electrical insulation testing, climate you’re all collection – for now. Simply hang tight though becabenidormclubdeportivo.orge we’ll have some more tricks that the profession for megging a motor coming out on the blog soon. Specifically, if you’ve been looking for a step-by-step procedure becabenidormclubdeportivo.orge that running assorted insulation tests, you won’t desire to miss it.