Latest / The Refrigeration Mentor Podcast / Episode 305. CO2 Experts: Electrical Troubleshooting

Transcript

Episode 305. CO2 Experts: Electrical Troubleshooting · The Refrigeration Mentor Podcast

• 0:00
  Welcome to another CO2 expert. So glad that you're all here. We're gonna be diving into CO2 electrical troubleshooting. If you have and been to some of the podcasts or the YouTube videos with some of the experts from around the world, definitely go check those out. Like highly recommend.
• 0:01
  So if there's things that you need to learn reach out to me@refrigerationmentor.com slash contact or just email me at trevor@refrigerationmentor.com 'cause I'm here to help support you in your team, in your business. We're getting into electrical troubleshoot today. Something that I'm getting better and better at.
• 0:02
  It is electronics. I was having a conversation with a business owner last week here in Canada, and he was, he was telling me that, , I did supermarket for a long time. Now I'm in the VRV and VRF world, and he is like, Trevor. It's the, it's the same like V-R-V-V-R-F is probably more complicated than than supermarket.
• 0:03
  But all that knowledge that you have already. From commercial HVAC or the V-R-V-V-R-F world and you're coming into the supermarket, you're gonna learn it so much faster than when I started out. Brand new, not knowing anything really about what a TX valve is or how does it work, and airflow and all that stuff.
• 0:04
  Expert technicians from all around the world or even manufacturers. 'cause we're really trying to share knowledge to help you if you're a technician out there, if you're a designer out there and look at more people continuing to join. I love this. People who care about uplifting the industry, and that's what refrigeration mentors all about is helping uplift the industry, help you get to the next level in your career.
• 0:05
  And this was a HVAC unit. It wasn't a CO2 unit, but it doesn't really matter. Had the disconnect off fully off. But he didn't go and just start touching and pulling the wires off. What do you think he did? He took out his meter. They took out their meter, and they went to each leg of the power source to ground, and all of a sudden he had voltage there with the disconnect off.
• 0:06
  Because that would've been a not very good day for that technician. So it was smart technician. So always make sure you check that because maybe that disconnect is, is broken. Maybe that contactor has failed, but always lock out, tag out. I know this takes time. I know I used to be bad for it as well, but it was that one time that someone turn on a, a, a switch when I'm cutting wires and all of a sudden I get a shock.
• 0:07
  Right. Like you see right here, they have it written. Okay. This is a time delay relay coil. Okay, so now with coil what is, now we gotta think about what is actual a coil. When someone says this is a coil, it's actually just wire, , a bunch of wire wrapped around a coil, and then when we energize it, it will make an action happen.
• 0:08
  That is the biggest key. It's in de-energized position. So after you go into that mechanical room, after you get the the specs from the manufacturer or the customer, you want to take a look at what is on that drawing. What is on that diagram? All the different components and how it works. 'cause if you don't understand how the electrical wiring diagram works is gonna really be tough to troubleshoot.
• 0:09
  Is it a temperature? Is it a pressure? So each manufacturer's gonna do it a little bit different because the biggest thing that we need to do as a technician in the field is match up the electrical wiring diagram to the. Piping schematic, and I talk about this in all my programs. , if you get into the supermarket Academy, you see I focus on a whole mo multiple lessons in the academy talking about P and IDs or piping schematics, because this is so important for you as a technician to understand.
• 0:10
  Just like oil. Oil was really hard. One too. Where's the oil at? How come it's not in the compressor, it's not in the reservoir. Where's it go? How do I get it back? All those, all those questions. Listen, should I add oil? Should I take oil out? This is the similar to electrical and starting with the safety first, like we just talked about earlier, and then getting into the electrical symbol.
• 0:11
  We wanna. We don't wanna be pulling all that stuff off. Yeah. Steven Key. The testing circuit is dead. We just talked about that a little bit earlier, just before you, you jumped on. That's huge. Huge proving the unit gives out no voltage. I love that one. That's step number one in safety. You shut off the disconnect here.
• 0:12
  Put the electrical wiring diagram down. You get your meter out. What is my voltage across L one to L two, L one to L three and L two to L three. Write that down on the electrical wiring diagram. This stuff was game changing when I started to do this. Going out to do field startups with contractors and manufacturers when, and starting writing down all this this information.
• 0:13
  It's no different than refrigerant. That refrigerant is gonna move to the path of least resistance. And it's gonna go there. And this stuff is, is so, so important. So that, that's number one, understanding that diagram, getting the diagram, and then start labeling or writing it down so you get an idea of how that system is supposed to work.
• 0:14
  'cause that's the only time when customers are calling. They're not calling you when everything's running Good. Hey, how about doing some testing on on on my system? That's not the way it works. We as technicians are going out to put out the fires and we don't always have the opportunity to do that electrical learning.
• 0:15
  It's actually the map. This is what I call the CO2 map, and we see up here. There's some information also. This is 1, 1 10 to one 20, single phase 60. So understanding what that information needs. G one C one, that is another piece of information that from that specific manufacturer. And then down here Copeland, scroll digital.
• 0:16
  But you're doing a retrofit and you gotta pull out some equipment, but you gotta keep some equipment running. But it's a 20-year-old rack. There's no labels on the wiring. There's, you don't even know where the wires go because it's just. All years, people just putting twist marts on there. Just really, really just making it work.
• 0:17
  I know this from just looking at the, the labels on it, which is an IDCM controller. So this would be the digital controller. So, well, how does it really work? Well, first step, we need power coming in. Power coming in is rate up here. This a dash E two that is actually from another page. So when you're reading a schematic, we know this is de-energized position, but there could be three or four or five different pages that lead back to a a one page.
• 0:18
  And that's kind of the board. And so here's an example of it right up here. It could be a Microthermal. It could be a Danfoss. It could be RDM, it could be corral. It doesn't matter. You want to get a good feel on what, what it's going. 'cause here's the labels. What is great? There's some labels right there and there.
• 0:19
  Here's another one right here. Analog output. Well, what's an analog output? Well, that's one of the things that you need to dive in and learn about controls because this here. This C one and C two needs to take a one to five volt DC two run that digital. So now here's an unloading soil node right here, a little schooling right here on this low temp compressor or subcritical compressor.
• 0:20
  You're gonna have digital compressors. You're gonna have mechanical capacity control compressors. There's gonna be a lot of these different options, and you even see them on HFC systems. And this is not new. I've seen it 15 years ago on racks. I've been, I worked on tons of pilot project on energy efficiency optimization supermarket stores.
• 0:21
  And it's gonna be all coming into this point here. So our job using the meter is putting it on. This one's an example for DC voltage. What? Voltages am I getting into this controller? So is it a so it's a one to five volt dc I know this compressor starts up at 1.44 volts DC 'cause I underst worked on tons of them.
• 0:22
  What our volts DC is gonna start to drop off, and then our loading and unloading is gonna change. Okay? So this is the basic run through of how that that works. But what's important, we need to understand, well, how does our power, our circuit, get our compressor running. So this here is our compressor circuit, so we need to understand a lot what's going on on it.
• 0:23
  I had, I, I didn't know what else to do. I didn't know the difference at the time. But if you put a fuse in and it pops again, there is something wrong. Usually there's an electrical issue, there's a short, the motor could be short if there's a motor there. In this example, we got a low pressure go control for the low temp group.
• 0:24
  And this is what's great about the CO2 manufacturers today to making it super easy for us. 'cause they are more of a complex system. There's just more of it. Is it any harder than another refrigeration people? System? Some people say yes, some people say no. It's not as hard as this. It's harder than this.
• 0:25
  If we get a phone call from the store saying, Hey, compressor one is down. It's not running. We got a proof failure. That's the alarm that maybe you only see. Customer won't know that. They'll just say that the system's down. You get it and you see a proof failure. Well, maybe it's because it went off in low pressure.
• 0:26
  But here's an example right there that you can adjust and change. Do not change any settings if you don't understand why you're changing it. The reason you're changing it and what it affects it has on the system. Just remember that maybe you can do it for a test, but make sure you put it back. 'cause if you don't know why you're doing something that could lead into chasing your tail for a while, not properly troubleshooting the system and maybe getting something up and running.
• 0:27
  So in the, in the master controller, there's gonna be a suction group set up and that suction group set up the stage on the different compressors. And then this one here, if we have any demand, this is the lead compressor one, this will be closed. So now we have power going through here. We got power going through here.
• 0:28
  So you don't break components and you don't burst pipes, and you don't pop pressure reliefs on it. We go through here, we have voltage coming through here, and then we go to this next device, DLT. I don't have a picture of A DLT, but this is discharged line temperature. And this may be named differently for other other manufacturers.
• 0:29
  If that is okay, we still got voltage going through here, so. Remember, we're not gonna go up here because the coil, they don't draw the coil in here. If we are energized, this coil right here, 'cause we have power coming down through here, up through here, coming in through here. So we energize this coil.
• 0:30
  So C one right down here. If we look down here, we have a, this was a normally closed relay on an auxiliary contact. I like that they put AC there. I understand what that is. Auxiliary contract on there. When this is energized, that opens up our cranky heater is not on. When this de-energize, we satisfy, we open up here, we'll say, then that will close, and then we have.
• 0:31
  We can break up the circuit, we can go right here. If we can go right here, and then all of a sudden if we have voltage or no voltage, that is gonna tell us the difference. Is the, are these open or are these closed? That's a big deal because if we got, if we got voltage there across there, we know these are closed, but all of a sudden, if we don't have any voltage here.
• 0:32
  So that is why we have R two light. So, and then that would be relay two in this circuit. So these are just a couple of tips on, on troubleshooting. What's, what's important though, is I. First step is that safety, making sure you're not touching any of the wires until you check it first. Second step is having that wiring diagram and finding the right page, going through it back and forth.
• 0:33
  And the piping schematic, like always, this is what we talk about in all our courses. Making sure you're getting into those s schematics, piping diagram, as well as the electrical wiring diagram. You'll see that heavily in the supermarket academy 'cause it's really, really important to dive in. Here's a, here's an example of some relays that are out there.
• 0:34
  You'll see some of these, and it, like I said, it could be different brands different brands of, of relays. The big thing is, is to understand, so I took a quick picture at one of the sites I was at. We can see here's one, one's right up here. Here's five five's right here. Here's nine nine's right here and down 13 and 14 are down here, right here, 13 and 14.
• 0:35
  So now this normally open will now become normally closed. This, and this is how it works. We energize it, we are switching the contacts. What's what's convenient about these? You can have some normally closed, normally open, depending on what you are building in that circuit. So that's so, so important and I've seen tons of these fail or run into issues before Lots of 'em I've even seen and heard of these running into issues getting moisture inside there.
• 0:36
  Maybe inside here the switches. Have failed. Maybe they weld it shut. Maybe they're not switching anymore. Maybe this, this here broke inside here. There could be many, many different things. Maybe. Yeah, those a few things. So just double check when you're running into an electrical issue, even though the light says it's on, you gotta verify that with your meter.
• 0:37
  So as your meter's on there, it's got tons of videos. I've done them on LinkedIn or Instagram. Go check them out where we actually test it. I want you to go there and test it yourself so you understand. See what it looks like. So you agree. Heat the bulb up, the resistance goes up and you can watch it start to go up.
• 0:38
  And then as the temperature changes, it changes that resistance chart. So be very cautious with that. And then when we get into testing different pressure probes. This is, this is so, so important as well. Like the easiest way is to have your trans-critical gauges. And if you're gonna check a, like a discharge one, you put your trans-critical gauges or you put a trans-critical service gauge.
• 0:39
  What happens is that, that as that pressure changes, it changes that feedback signal. So first we wanna take our meter and we wanna check, do I got five volts there? Next I wanna check what the signal is coming back. This is the linear scale. You can go to any, any linear scale calculator, put the, the numbers in and it will show you where you're at, what the pressure is.
• 0:40
  That's a lot. That's what do you think so far? Was there some value into that? Taking away some of that electrical troubles. And I know a lot of you listening here and watching here, you've, you've, you've seen this and you've done this before, but it's getting to that next level. And I want you guys to teach other people this stuff.
• 0:41
  That's what we do here at Refrigeration Mentor. 'cause we are seeing people getting new jobs, moving into service manager role, running, running their business better, getting technicians fired up, fired on all cylinders, leveling up, and we love that stuff. This is why we do this stuff. We do also have some CO2 courses coming up.
• 0:42
  So call up the manufacturer if you have to. It might take a few days, sometimes get the model, get the serial number, find the person to get you that diagram. Maybe the end user has it, they're out there. It's out there somewhere because that, that system or that would've had been built by someone. And you need electrical wiring diagrams to build a system.
• 0:43
  Sometimes that frustration barrier, like, man, we've got this again, and it's the same wiring issue from the same manufacturer in the same spot. Well, there's someone at that organization that wants to help you out. Sometimes I'm the bigger, the bigger manufacturer that takes a little bit more to make things happen versus a smaller one.
• 0:44
  trevor@refrigerationmentor.com, you can go to the website and check out the advanced design course and book a call with me because this course has changed people's lives. Honestly, I have a technician outta New Zealand who has did, he is for, he was a tech, he's a technician, but he wanted to get in design.
• 0:45
  And there's gamechanging stuff. We had people from end users in there. But this program, this design program, if, if anyone that's interested in level up in CO2 trans critical design it's gamechanging. 'cause not only design course, a lot of people go into the course and it's only design.
• 0:46
  Good friend Andrew Freeberg. He's a, he is a ambassador in the community. This guy is on fire right now. You should see him. He's crushing jobs. He's training people. He's, he. Solving problems that people just aren't able to solve. And he, he saw solving them and, which is great, and, and it just 'cause he's out there putting the work in Day in Dale, love all this stuff.
• 0:47
  We're there to help support you. If you want to get kicked off just so you can't, you're not able to get into the refrigeration mentor training programs yet. You can get into the hub where we're sharing tons of knowledge. There's, there's free courses in there. Hey, we wanna help level you up. That's what we do here at Refrigeration Mentor, lifting up the industry.