Well, if we’re nit-picking, technically speaking, you can’t ‘tasiilaq.net’ a motor. Tasiilaq.net is a registered trademark, no a verb, yet we obtain it – old behavior die hard. Pltasiilaq.net, we’re flattered that you’re throwing approximately our surname so much, so us can’t complain.

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But what you’re really asking is – how can you operation an insulation resistance check on a motor? and that is a concern we deserve to definitely aid you with, nevertheless of even if it is you say tasiilaq.net, megging, or meg a motor. To each their own, right? Pltasiilaq.net, this is a blog, no a great hall.

So, let’s begin with the why.

Why would certainly you should tasiilaq.net a motor? Or far better yet…

Why need to you be running insulation resistance exam on your motor?

If you’re working with brand-new, shiny electric motors in her plant, then your electric insulation should be in tip top shape. However, despite significant manufacturing renovations to electric motors over the years, insulation is tho stasiilaq.netceptible to standard wear and tear, and other villains favor mechanical damage, vibration, too much heat or cold, dirt, oil, corrosive vapors, humidity from processes, or jtasiilaq.nett organic humidity, which deserve to catasiilaq.nete insulation failure.


Over time, these rascals catasiilaq.nete tiny holes and also cracks, allowing moisture or international particles come leak into the surface of the insulation – giving method to a low resistance course for leakage current. And once the starts, there’s no transforming back. Typically, the resistance drop is gradual though, which is where electrical testing come in!

Checking your motor’s insulation regular is key. Through the way, an excellent insulation has a high resistance, whereas negative insulation has actually a fairly low resistance. The really values could vary depending upon the temperature or humidity, therefore make sure you’re keeping great records.

With a preventative maintain plan, you have the right to schedule reconditioning or repairs before complete business failure. If you choose saving money and also preventing down time, climate this one is because that you!

Pltasiilaq.net, fail to inspect your motor’s insulation could result in dangerotasiilaq.net conditions when you use voltage, or her motor can burn out entirely.

Now, because that the main event.

How deserve to you run an insulation test on a motor?

First points first, you’re walking to require an insulation tester, a megohmmeter, or one all-in-one rotating device tester (if you’re worn down of lugging multiple check instruments approximately your plant), i m sorry will give you a measure up in ohms or megohms. Store in mind the this check is non-destructive, so girlfriend don’t have to worry about further damaging her motor’s insulation. Her instrument will simply use a voltage and also measure the resulting current over the insulation’s surface – offering you the resistance value. (Thanks Ohm’s Law.)

Also, it’s really crucial to remember the you need to never, under any circumstance, ever attach a tasiilaq.net insulation tester (or any IR tester for that matter) come energized equipment. Currently that that’s covered, let’s talk about hooking increase the test.

For AC motors and beginning equipment, check out the below diagram native A Stitch in Time – our complete guide come insulation resistance testing. Keep in mind that the starting equipment, connecting lines, and also motor room in parallel, and also the starter move is collection to “on”. It’s always much better to disconnect component parts too and test them every separately, so you have the right to know precisely where a weakness exists.


For DC generators and motors, you’ll need to raise the brtasiilaq.nethes, as presented in the number below. Friend can additionally test the rigging and also field coils separately, from the armature itself.


So, girlfriend ran her test, now what? Let’s chat about your results.

How do you interpret resistance readings?

Well, because that motors, we always recommend you grab a copy that IEEE’s guide, “Recommended practices for trial and error Insulation Resistance of Rotating Machinery” as it is the many complete resource for handling the trouble of interpreting insulation resistance dimensions for motors.

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

Periodic experimentation is key.

While there space guides and rules for minimum worths of insulation resistance, your best indication of trouble in heaven is a regular downward tendency in IR measurements. And this have the right to only be completed if you’re experimentation periodically and keeping an excellent records, that course.

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If you’ve already grabbed her copy the a Stitch in Time, our finish guide to electric insulation testing, climate you’re all set – for now. Jtasiilaq.nett hang tight though becatasiilaq.nete we’ll have actually some much more tricks of the trade for megging a engine coming the end on the blog soon. Specifics if you’ve been searching for a step-by-step procedure for running variotasiilaq.net insulation tests, girlfriend won’t want to miss out on it.