And then BAM right away, trips, the pop or kick it kick it? Kick it? Kick it kick it pop? It's BAM really clean bad. You definitely hear that now we don't know where that is. We just know. Okay, our short is to grab thanks for watching this video.

It is about a compressor that is tripping a breaker blowing a fuse, and often when you have a compressor, that's tripping a breaker blowing a fuse. You don't first know whether it's the compressor or something else in the condensing unit, we're talking about a typical kind of split system here, which is the most common type of air conditioner that you're gon na see. So you have a breaker, that's tripping for the condensing unit and you got to figure out what's causing it and the easiest way to start doing. That is to do a visual inspection.

Look for possible. You know rubbing out, wires or or things that you know. Don't look right, shorted grounded things like that, but when you have a breaker or fuse that's blowing, slash tripping. What that means is, is that you're drawing too much current and generally, it's gon na, be significantly too much current, because if it's just a slight over amperage or overload condition, then generally the motor is gon na shut itself off via internal overload.

So when we say an overload condition, generally motors within air conditioners are going to shut themselves off or they're gon na have a starter or something else that has overload protection in it. When a fuse is blowing or a breaker is tripping, that's usually a more extreme version and we call that a short or a grounded condition, and so often when we're talking about a compressor winding, which is the wiring inside the compressor motor, that's touching ground. It's touching. The casing, or something else inside that compressor, will call that a grounded condition or a shorted to ground condition.

That's a really common cause, a compressor tripping, a breaker. You can also have a situation where you have a leg to leg short, where the windings themselves are shorted together. That's really really tricky. So warning.

It's really tricky to measure that ohm reading from winding the winding, because you have to have a really good ohm meter and you have to have the data that says what that ohm reading should be in the first place and it's very low generally on compressors again. This video here is focused on compressors, as Bert's gon na show you a real life example here, but keep in mind. You got to have a really accurate, ohm meter and you have to have the manufacturer specifications that shows you what that ohm measurement should be. If you take a look at this screenshot, this is the when mobile, app and so using the Copeland mobile app.

You can find the resistances if you've got a Copeland compressor. That data may be a little trickier if your compressor is not a Copeland compressor but again keep in mind that it's extremely rare for compressor to be shorted leg, the leg without being shorted to ground. When I say extremely rare, I know I'm gon na get the emails to people saying it happens to them all the time. I'm just saying in my experience.

Generally speaking, compressors are shorted to ground, so birds, gon na show you a traditional situation of how to diagnose a compressor and whether or not it's shorted to ground hope you enjoy hey. So I got a compressor here. That's shorted, I'm gon na do a quick video on some do's and don'ts when it comes to diagnosing a shorted compressor and then I'll just walk you through what I do show up our breaker strip right. So I'm gon na go ahead and reset the breaker and then BAM right away it trips.

So I know I got a really significant short: it's not like the pot or cukoo cukoo cukoo. Kick it kick it pop. It's BAM right. When I turn on that breaker.

It trip okay, so that's our condenser breaker, so I'm gon na come outside and the first thing I'm gon na do is just check if this is a short to ground. Try to confirm that with my meter, I'm gon na set it on ohms and then I'll put one leg on ground. This ground is the most common. You know short, you run into one leg on ground powers off inside the breakers off and I'm gon na check to see if we have a short on our high voltage, so I mean we're showing it kind of a path.

I mean that's. 113. That's still lots of resistance there not a clean path, we'll check the other side and that that's pretty much a perfect path. We got zero and showing zero resistance from my high voltage on this side path to ground.

Let me change the function here. That way you can hear when you're checking for continuity here. So if it's not a really clean path, you're not gon na hear that hear that mm-hmm all right so check this out. So on this side we did.

We didn't have a really clean path and then over here really clean bath. You definitely hear that we have a short to ground now. We don't know where that is. We just know.

Okay, our short is to ground great. So now look. What are we doing? Next? We're gon na do a visual check. Let's go over the unit, we're gon na just gon na check wiring real briefly, because you know it's common to have a wire rub out and that visual check is very important.

I've done that already here next thing I is the compressor, that's probably the number one reason I have a breaker that trips immediately like that at the condenser is a shorted compressor, so we're gon na test that it's crucial chicken. Your compressor that you remove your wire leads okay, and on this you know, pay attention to where you're doing this. Not not a lot of these old compressors are labeled. Like you can see here, we don't have a label for start common and run so save yourself.

The trouble so now we've disconnected the wiring from our compressor. We could check the compressor directly to ground from the terminals themselves, so if there's a short somewhere in the wiring and that's what's causing it, then we're gon na pick that up now you can come over here and see if this has changed. Okay. So now it's the ground, we don't we're not getting a path, so we've just isolated that removing that those plugs on the compressor made the difference there.

In this situation we have a really clean path to ground. The short is pretty obvious, so you know I'm picking it up with my meter. They pulled out the mega a mega meter, which is sometimes needed when you have insulation, breaking down on your windings and periodic shorts for breaker, maybe tripping right away in their load. You don't pick it up as easily with just your hands.

You know regular handheld meter, so I'll show you that next, let's check on each you can do that. I'm getting an immediate connection to ground. Our common winding is what is shorted to ground internal to the compressor. So now we've isolated to the compressor with our meter.

I wanted to also show you using the mega meter because sometimes you're short, you can't pick it up as clear with your handheld meter. So a mega meter will actually dramatically increase the voltage. It can be very helpful or necessary, sometimes for confirming that pressure diagnostic. So I'm using the the b-side insulation tester, you leave the wires hooked up and it's actually a short somewhere in the wires, so always disconnect the wires.

Isolate your compressor. I'd already done this, so I hadn't yet mentioned it in the video but uh making a really clean connection for your meter, clamps on or touches it's important to actually have currently read resistance. So what the mega meter does is it increases the voltage between you two immediately. It can travel through a higher amount of resistance to voltage than what your handheld meter might be able to produce to travel through and and and so then you can see where there's a short, I'm gon na put it on 500 volts.

That's pretty typical for a mega meter and I have a range option and you know best of all point go ahead and leave point in there. So for a second, I thought it needed two hands. You know push it in Tess. I can actually push down turn it to lock.

In that extra hand, for this camera and then check first, I'm gon na check on the terminal that my handheld meter would not actually pick that the short following that I have a bunch on run last time, yeah. So you can see that's a perfect path, so you know at 500, volts DC voltage we're getting perfect path from our compressor windings to ground make sense. So we've confirmed with our meter that the compressor shorted to ground a couple common mistakes, one is that you don't actually unplug the compressor terminals number two, which is probably more common as that technicians pulling out their mega meter and they're checking leg. The leg between common and run common and start or start and run on the compressor, their mega meter, of course, is gon na read that you have a clear path across the windings and usually it'll show you bad.

You know if you have the older of the set, go style, megameter it'll, just say bad on the compressor. So that's a mistake. We do not want to make so you never want to actually test leg to leg across your terminals for a shorted compressor. That tells you nothing and then I would say one more thing: if you have a scroll compressor, you will sometimes actually have an electrical connection between the windings and the casing that you can pick up with a mega meter and if you're, using like the Seco, it Might tell you this scroll is bad at 20 ohms of resistance, which I believe that Copeland will tell you that a short to ground a short to ground compressor is gon na read below point five for install compressor.

So I had a situation where they tripped a breaker. Damn damn damn like that, and I isolated the compressor i hook up the set, go meter, push the button and it shows bad. You know somewhere around 20. It just shows bad.

So I was ready to condemn that compressor. Until I noticed a capacitor was swollen and it had burst outside of the capacitor, and so I was like huh. Let me just see what happens hook up the capacitor with a new capacitor plug it into compressor turn on the breaker. Everything runs: fine, don't test leg the leg to confirm a shorted compressor.

That tells you pretty much nothing check your wiring. Do a visual check check your start components, you know confirm and then the last step, which we often call the redneck test. It's crucial. You just regard your tools, your meter, and you just confirm through isolation that, what's causing the breaker to trip.

Actually is the compressor - and I often use this to show the customer, because this is sometimes it clearest example to give them with the compressor plugged in the breaker trips immediately. We remove that and I put some electrical tape on there. So nothing is shorted out we'll go ahead and put the fan back on we're gon na hook the fan up all in its proper places, then we're going to go inside and hit that breaker and the breaker should stay on. Nothing should be causing that to trip.

Come out here, the contactors pulled in a fans running there's no other problems, we've isolated that it's actually the compressor shorted and not a wiring harness somewhere, not the condenser fan motor, which will happen, but rarely it'll short to ground internally and proven. You know that to the customer and to ourselves that our tools are working, it is actually the compressor shorted. So don't forget that last step and that's that's pretty much it. I think.

Hopefully this is helpful for you. It's not a pause right here and just talk to you about this chart that I got from Copeland, and this really simplifies this does not start instantly built blows fuses or trips breakers. So anytime, it says blows fuses. That's also applies to trips breakers.

So first question is: is the compressor grounded well figuring out if the pressures grounded is fairly easy and generally gon na use just a typical home meter and go from each terminal on the compressor to ground? Now keep in mind single-phase compressors, typical single-phase compressors have a run winding and a start winding common is a terminal, it's a point between run and start. It's not it's own winding. So, even in this video Burt and initially when he said the in terminal, he said the common winding, which is a common mistake for us to make common mistake, because it's common but you're gon na measure from each one of those to ground to see which one Is potentially grounded with the wires off of the terminals? Because, again, if you leave the wires on the terminals, you leave the spades on the terminals, then potentially could be the wire that's grounded and not the compressor itself. So I always pull the terminals off.

Take a picture or mark the wires, so I know how they go back on then. I measure from each terminal to ground bird also shows that if you're gon na use a mega meter for this purpose generally not necessary, but if you're gon na do it, then you have to take into account that you also measuring from terminal to ground. You don't use a mega ohm meter from terminal to terminal and also keep in mind that with scroll compressors, often that ohm measurement to ground is going to be significantly less than that. Keep that in mind when looking for this grounding or shorted compressor with a scroll compressor.

The motor is down meaning it's immersed in the oil and refrigerant, and it can often measure a lower ohm rating than you would see on a typical, more open motor type of configuration, so you'll often see lower than that twenty mega ohms to ground on a scroll Compressor once you've checked whether or not the compressor is grounded. If the answer is yes, then you have to replace the compressor. If the answer is no, then you check your winding resistance against the manufacturer data. If it's Copeland, then you use the Copeland mobile app.

If it's, some other compressor than you would have to refer to the manufacturer data, keep in mind that many ohm meters are not accurate enough to do this test. Well, so you really have to know something about your meter and whether it has that level of accuracy. Alright, so that's it that is checking a shorted. / grounded compressors blowing tripping a breaker again we're going to talk more in future videos about locked, compressors compressors that have internal compression issues.

This specifically, is about ones that are tripping a break or blowing a fuse, and this is specifically what you're going to see those of you who talk, who want to kind of throw out there, that locked compressor sees compressors tripping the breaker. That is almost always going to result in an internal overload, not in a tripped, breaker or blown fuse. Oh, that helps we'll catch you on the next video.