Latest / The Refrigeration Mentor Podcast / Episode 259. CO2 Experts Live: Electrical Troubleshooting with Rusty Walker

Transcript

Episode 259. CO2 Experts Live: Electrical Troubleshooting with Rusty Walker · The Refrigeration Mentor Podcast

• 0:00
  Trevor: Welcome to CO2 experts live, super excited here, having the top CO2 experts from around the world. Uplifting the refrigeration industry, technical training, deep dive and troubleshooting. So you as a technician in the field and engineer in the field can get some quick tips on how to troubleshoot.
• 0:01
  Co2 systems today. I got a special guest, my good friend, rusty Walker, one of the top co2 trainers from around the world trained tens of thousands of people over the years, and we have the pleasure of walking through co2 electrical wiring diagrams today, rusty, welcome to co2 experts. And we want to do some deep dive. So rusty, I'll let you kick it off right away.
• 0:02
  Rusty: So I love this screen to begin with because we have this conversation all the time. Is it electrical problem? Is it a mechanical problem? And we actually get into no, no, it's this is that.
• 0:03
  And so we have to understand that there's a marriage between electrical and mechanical, and I'll go through a little bit of that later on. And so, Like any language when I learn a new language, I have to learn what verbs and the nouns and I have to learn how to speak that language. And so when I'm starting to talk about electrical, I have to understand electrical wiring diagrams.
• 0:04
  I have to understand the symbols. So when I'm turning something on and off, I have to know, is it a light bulb? Is it a solenoid? Is it a switch? Is it? What is the component? So I have to understand the electrical symbols that tell me what it is. So here's a couple of them that I thought were pretty important.
• 0:05
  You can see I have a. relay. We use so many relays and contact her. So this is a magnetic coil that's going to energize for me to do some type of work. That means I can have a normally open contact that I closed to turn something on or I could energize this and take this normally close contact and I can open it and turn something off.
• 0:06
  There's a single, this is a double pull single throw switch. This is just a Toggle switch. It's simply, I've been on systems where we guys gone through it and forgot to check the switch. Is it on? Right? Here's a momentary push button. I may have a pump skid where I am. I have a temporary alarm, and I just want it there until you see it.
• 0:07
  Then you push the button and it's off A simple fuse. It's a straight line. I have a high pressure. If I don't know if it's open on rise, if it's closed on rise how am I going to troubleshoot the system? I have a time delay by this little diagonal line here. That's a time delay. I'm going to look on the drawing.
• 0:08
  How long has it been time delayed? Is it a 52nd? Is it a two minute? What is the time delay? This is when I'm looking at pressure switches. You're all going to see these domes. Well, I have to understand that So before I even start to troubleshoot electricity, I really need to spend some time understanding the symbols each We use basically the same but every vendor may use a little bit different symbol Look at the legend figure out what he means and what is that?
• 0:09
  Is it a solenoid? Here's an example of a solenoid That has a light on the solenoid and I have a panel light, so I have two actual lights from the solenoid energizers. And of course, there's always the all important grounding look. We have to know where the grounding is. We have to make sure things are properly grounded.
• 0:10
  And I love the fact that they drew a little bit of a little ground thing here, right? So it's showing me that the, the rod is put into the earth. Earth is ground. Always remember voltage. When I'm troubleshooting electricity, always remember. Voltage is trying to return back to source when we're talking about control circuitry.
• 0:11
  And there's so much of our systems that we're not talking about motors and that we're talking about a 2 0 8 circuit, a 1 10 control circuit. Always remember it's, it's kind of like water. If you want to think of it that way, but electricity is always trying to return back to source where it was generated.
• 0:12
  Right. And we'll kind of cover some of that. No matter what electrical book you open, no matter what basic book you open, you're gonna see my, my Hero, Michael Faraday. And you're gonna see magnetism because think about that. If I take copper windings, run around an Iron Core, I create a electromagnet, I turn it on, do that in the basement, go into your garage, grab a little iron core, wipe some windings around it, pop on some voltage, make sure you're not, it's, it's grounded and it's something not.
• 0:13
  Conductive and look at the mag. Put your mag, put your amp probe around it, and look and see that you're going to read the intensity of the magnetic field. Anybody, if you've ever done Ohm's Law and you say, we, we represent current with the term, with the letter I. The I stands for the intensity of the magnetic field that we're reading.
• 0:14
  Electrons are passed through a wire that copper wires were moving. These electrons. This is the same thing. It's electromagnetism. So let's keep that in mind. We're trouble troubleshooting this. Because it's going to be important to us, and I'm going to show you other things. I want you to think about with magnetic fields and transformers as we go through here towards the end magnetic field.
• 0:15
  I'm going to turn on my I'm going to pull up. If you ever look at an ice cube relay and really look at the side of it, you can actually see the armature come up when you energize it, and that's just small little armature coming up and touching contacts. And so I have to understand how that works, right?
• 0:16
  That's a magnetic. Pulling it up when I energized pins 13 and 14 on the on the relay transformers. This is a function of magnetic fluxes But we have multi taps how much of the windings am I going to be using how much of this transformer? So by having a multi tap I have a a single raw a single core and I have different Taps off of it.
• 0:17
  And based on how much that core I use and where I tap that wire is where I'm stepping down my voltage, right? And so that's what we call these. We all have a multi tap transformer tapping it. I'm tapping it off the coil of that transformer. And so that's what we mean. If we look at if we look at our the poles outside our houses and we see those massive transformers stepping down 17, 000 volts to 2 40.
• 0:18
  However, I tapped that transformer. The windings I use creates the step down voltage that I want to use. All right. And I got to give props to I gave props earlier to my man, Michael Faraday. He's the one that came up with this. He was actually one of the few scientists that Albert Einstein had his picture where we have Einstein's picture up.
• 0:19
  Einstein had Faraday's picture. And by the way, for all those people say you have to have a degree to work on this stuff, Faraday didn't have any of it. And he's probably one of the greatest scientists we've ever known. So just giving him a little bit of props. So here you can see my coil voltage. That is what turns this thing on.
• 0:20
  Then I can see this is my Base. This is the input. If you will. This is going to be 9 to 1 normally open 9 to 5 normally closed. So I can do with this one transformer or this little relay. You can see I can do multiple tasks. I can wire this one normally open. I could not wire this one normally closed. So I energized the coil.
• 0:21
  I can turn this on and this off. So when I'm sitting there troubleshooting this and thinking about relays, understand it's not a single phone. It doesn't have to be a single function. And so we need to remember that. And remember the voltage here, maybe two Oh eight, maybe 24 volts DC, maybe 24 volts AC.
• 0:22
  That's important for us. Don't do like me. I was troubleshooting a circuit one time in my own training room. I had a relay bad and like every other mechanic on the planet, I had a bad, I'm just going to pop. Get the relay next to it and we'll pop it in just to check and see if the relay is good. So I do it.
• 0:23
  I pop it in. I go, Oh man, two bad relays in one little circuit. This is stupid. And then I grabbed the third relay because the engineers and the, the OEM and put it together. They're just stupid. And so I popped the relay back in This time I see the magic smoke leave. And I looked at the coil, went, Oh, I just popped into 24 volt to 24 volt DC coils into a 110 volt base, so make sure you're focused on that because you can let the magic smoke out.
• 0:24
  And so just make sure when we're, we're looking at these, we're checking the voltages, make sure we're looking at the coils when we're looking at transformers, make sure we're focused on how many VA do I need? Is this the right VA, the bolt amps? Is it big enough? Is it big enough? All right. All right.
• 0:25
  Thanks. Here, I told you right here, you can see the common pin there. You can see the normally closed and then normally open. It's barely open. But when I hit this coil voltage, that's going to energize and pull this armature down and switch over to the normally closed side of that. That coil. So if for those of you who've ever wondered how these look and you can actually pop them out and look at them and you can see you can look like a like a fuse and see if the filament voltage is there.
• 0:26
  And so I just thought I'd share that with you because I don't know how much we do. And I'm telling you
• 0:27
  Trevor: just just go back to that. So explain just one more time for the new people. So when it goes from when it's not powered, you got no power to your coil. nine to one, which is the top one is normally closed.
• 0:28
  Right. And you can see that here. Yeah. And when you energize it, that white box that's in there, there's a coil under there. You can't really see the coil, but that there's a coil, there's wire wrapping under there. Like Rusty talked about earlier, when you put power AC, DC, one 20, two 40, That magnetic field pulls down that little armature and it magnetized it.
• 0:29
  And then just like Rusty said, nine and five now are closed.
• 0:30
  Rusty: And it's, I appreciate you saying that because one thing I always like to remind mechanics. Especially your younger guys and, and, and you're looking at the wiring diagram. I know personally, when I was a BB learning this, I had struggled with this.
• 0:31
  And when I was in the Army wiring diagrams are drawn. I don't care who the OEM is. This is when the angels sound. When I heard this, I mean the angels saying the sky's opened up and I got it. Drawings are drawn in the de energized position. They are off. And so you as the mechanic, you as the technician, you have to energize the circuit in your head as you're running through with your meter and looking for the circuit.
• 0:32
  Normally open when, when it's off. when it's off. When I en closes, I've turned it on close when when the circu to me that was like the e like, yes, you know, run naked going, I get
• 0:33
  Trevor: it.
• 0:34
  Rusty: We far. Sorry. Sorry. You di Just keep understanding and relays are so important in our circuitry. We have them everywhere.
• 0:35
  These are the precursors to 8RO boards, multiplex, 205, 204 boards are our relay output boards, right? We still have these, but I don't have to run through the board. Program. They can still do programming ish things with these relays. And when I say they're everywhere, I mean, they're everywhere. This is on a CO2 cascade overfeed system.
• 0:36
  Simply look at the relays here. That would turn the cases off. Right? And so you have to understand this logic in order to troubleshoot this. This is one of the most confusing systems for guys who don't understand it. And I get phone calls on this all the time. By the way, if anybody ever calls me with an electrical problem, I'm glad to help anybody and everybody.
• 0:37
  And I can work on. Now with the N-A-S-R-C, I can help everybody, but if you have an electrical issue and I ask you what voltage you're reading, and you tell me you're the meter's in the truck, the next sa thing you will hear is the busy tone or the, the phone tone because I'm hanging, hanging up. Do always bring your meter in with you.
• 0:38
  Always always bring your meter in so i thought the wiring
• 0:39
  Trevor: diagram too right get that Before the electrical wiring diagram make a phone call to the manufacturer Get the diagram. It should be at the rack somewhere if you're not reading these every day You're not going to understand how to troubleshoot electrical.
• 0:40
  That's that's it because every Systems is a bit different. So you gotta, you need the wiring diagram. Cause you can call Rusty up and say, listen, I have this circuit here. It's the control circuit, or it's the compressor circuit, or it's the condenser circuit. Here's my points. Here's the voltage going down.
• 0:41
  There's this transformer here. I'm not reading the right volts and it could be like someone just added another controller VA to open the electronic valve or not, but you need the wiring diagram. To troubleshoot this stuff,
• 0:42
  Rusty: the OEMs are happy if you call the OEMs because you can't read the diagram because you're working on a lot that's been there since 1980. Try to find it and and what you really want to do your goal is remember 85 percent of our Our service calls are electrical in nature, so it's important for us. And with CO2 and A two Ls, it's not, it's going to amplify, it's gonna be exponentially greater. So we have to get a, so I always do, I always say this, if you wanna get good, if you wanna be a good, not a good, a great mechanic, study your electrical drawings, look at 'em, practice drawing them.
• 0:43
  I always say a mechanic should be able to draw. You should be able, I should be able to give you that circuit circuit and you should be able to wire it to some degree on your own, right? That's your goal. That's what you, that's who you want to be. You want to be that guy who can start laying it out.
• 0:44
  And I'm telling you, if you're the dog that can read electrical when nobody else is, you're the dog, you're the main dog. So I'm going to do a real quick sample diagram real quick. This and then we're gonna get into a more complex one and I'm going to go into a little bit more So you can see right here.
• 0:45
  I have l1 coming here l2 here. There's a 208 circuit So I have this is l1 my red leg. This is l2 typically black So when this controller, this is a this is a corral controller a form a contact He's going to he says, okay, I need the condenser fans. So he's going to close the street. I, that happens at the controller in the lot, in the lodge, we're going to talk about that a little bit later, close that.
• 0:46
  That simply means I'm going to close that. I'm going to energize this. That means if for this to be energized, I should have voltage here and here to LA, right? When that energizes, that is going to open. This set of contacts, yes, that set of contacts are going to open. You're actually turning off the condenser fan.
• 0:47
  This is kind of backwards because they're not using a Form C contact, they're using a Form A. So they actually had to add this relay to open this to turn that off. Now you look at this drawing i'm hearing you guys right now going well, that's stupid It doesn't matter if it's stupid troubleshoot the drawing in front of you, you know, I hear people say all the time Well, that's not so and so is it you're not working on so and so's rack right now Troubleshoot the drawing in front of you.
• 0:48
  This is how this system is done Troubleshoot it understand it to turn this off. I actually have to close this All right. So let's look at the same controller Or this is the same controller, and this is, they only have Form A contacts, Form A versus Form C, Form C has a common, and a normally open, and a normally closed.
• 0:49
  Now Form A simply has a common, and a normally open. You can't make that decision. You can't wire it normally open or normally closed, so sometimes you have to use your relays to finish out the logic. Alright, so let's see what we're going to do here. Split condenser. If I close that, that's going to energize the split condenser valve relay.
• 0:50
  Okay, so what's that going to, is it going to turn it on or turn it off? I have no idea yet. So then I go, the split valve, CPR7, always notice CPR7, the OEM is going to Tell me if I have a coil called the relay, a contactor, and it's labeled CPR seven, turning a coil on by itself does nobody any good. I have to go find it.
• 0:51
  It may be later on that page. It may be three pages over on the wiring diagram. It just depends on how it's laid out. So I have to go find CPR seven. I find CPR seven. It is a normally nine and five. Normally open. We close that. Remember we said nine and one is normally closed. Nine and five is normally open.
• 0:52
  We close that and we actually just put it into split. Good? Everybody good with that? And remember, L1, L2. Doesn't matter if it's 110 or 208, 240. All right, and we're going to get to that in a minute, but that's a simple little circuit, but it shows you how we're using Relays to complete the computer's logic and how if I didn't understand that Or if I got whiny or if I just was looking at it and go well that really caused the solenoid should Energize or deenergize wait a minute look and see what the logic tells me and then follow it through with your meter Follow it through.
• 0:53
  You're the most important tool you have in your toolbox. As far as I'm concerned, 85 percent of our, our service calls are electrical in nature. Our most important tool is our meter. And yes, I've been converted. I am now a field piece guy. I hate to tell you old guys, but I bought my first field piece.
• 0:54
  I'm in, I got it. So my flukes are getting rusty. Ha ha rusty
• 0:55
  Trevor: I got it. I got so this this is so important, right? So you got to get into the wiring because it could be four pages down too Like when you're looking at a big system, there might be multiple pages. So you got to follow what it says It might say okay go to page four or page six or might have a special symbol on it But you gotta spend the time in these different manuals because every manufacturer is going to do a little bit differently To do the same thing You
• 0:56
  Rusty: That's exactly right.
• 0:57
  And a lot of times they just don't tell me where the contact is. Let's look at this one real quick. This is on a overfeed system. Love this drawing. I love it because I understand it.
• 0:58
  Trevor: Yeah.
• 0:59
  Rusty: When I first looked at what the hell, but I understand it. So now it's easy for me. Right. So, so I'm going to give you a couple of hints before we get too far.
• 1:00
  And, and the thing to understand is. Look, I'm trying to turn on whatever's on the right side of this drawing. That is my goal. And so PSC1, pump shutdown control relay, I'm going to be ahead. And we're going to see this on the next page. If PSC1 is not energized, Neither pump was beyond. So if I walk into this strong, this motor room, or somebody calls me and says, Hey, I'm on this over feed system.
• 1:01
  I can't get either pump to run, neither pump is running. Well, you just told me part of the problem. Yes, he was not energized. Well, what's in? Well, look at all of these safeties that are in that circuit. So any one of these relay, these safeties can turn this on. So I'm going to go, some of you guys are going to get a little, a little irritated with me here real quick, but I'm going to, I'm going to preach gospel here.
• 1:02
  So a lot of you, first of all, L1, L2, right? A lot of people. Want to go from here to ground unless you're looking for a short. That is no, there's no, you're reading parasitic voltages. You are not reading a difference of potential. Let me define and let me help you break difference of potential down. If I take my meter.
• 1:03
  And I put my red lead and my black lead on l1 on one wire or on a across the fuse. That's good I will read how many volts? Zero, there's no difference of potential in there There's no there's no energy there, but if I take that black lead and I move it over to 208 Now I read I'm moving over to L2. I now read 208 volts because there's a difference of potential through there, right?
• 1:04
  That's how a light bulb works. You know, it's a filament voltage, but there's voltage drop. So it allows that potential to go through. So my light bulb works. So here's the way I troubleshoot. I learned this in military. It's helped me. And it's, I'm telling you, if you guys practice this, it's the best way to troubleshoot a control circuit.
• 1:05
  So I'm going to take L2. Now on my meters, my red lead, I have a four foot red lead. I have a longer red lead. And here's why, because I'm going to take my black lead and I'm going to come up here to the control breaker. L2. I'm going to loosen it just a touch and I'm going to slide my black lead under L2.
• 1:06
  This way I don't have to touch it. I don't have to move it. Now because one of the things I want to do is I want to try to use one hand as much as I can because if I'm touching both hands on the electrical panel and there's a short in it, I just became, remember electricity's trying to go to source. So the quickest way to ground would be through me.
• 1:07
  And so I always keep that in the back of my mind when I can, I try to use one hand. So if I tie that black lead to T2, L2, then I can use, put my magnet on my grand, my brand new field piece meter, and then I can go. And so PSC one's not working. It's the pumps are not. So let's do this. So I just tied my lead to T2, L2.
• 1:08
  I come up here, let's just make it easy. I'm going to pop it here. I'm putting my meter right here. I have zero volts. Well, it's probably not this coil. He's not getting voltage. That means something along this path has killed my voltage. So me I'm lazy. Be lazy because when you're lazy, you use your head more.
• 1:09
  And so I'm going to the circuit. I'm gonna go. I'm gonna break it in half. So I'm going to go, that NRO board is right next to me, in front of me, in my circuit panel. So I'm going to pop on board one pin seven. I'm going to go to the output of that board. It's an easy place to find, boom, I put my red lead there.
• 1:10
  I got 208. Good. If I got to away, which way do I go? Why don't go that way? Because that means that's closed. My pressure is not high and this output board is closed because otherwise I would not have voltage. So since I have voltage, I'm headed this way. If I wouldn't have voltage, I would go back this way.
• 1:11
  Probably to this pin here. It doesn't matter. I just, I like to make it easy. I don't want to go component by component by component. I try to break off three and four components at a time because ice cream is melting and I want to keep that store manager out of my hair. So, so but let's say our circuit, I went here, black lead on T2, my red lead here, 208.
• 1:12
  Perfect. Now for me I'm going to go with my, now I, I understand the circuit. So I'm going to look at this circuit and I'm going to go, okay, all right. If this relay point is good, easy to find, I'll go here. Okay. For our discussion, I'm going to find 208 there. So now what I know this relay point, I know this situation is satisfied.
• 1:13
  I know that relay is closed. All of this is good. Ah, I'm going to go to pin three on this relay. No voltage. I had voltage here. No voltage here. I go right here. Voltage. Then I go, what is this alarm? This is like four pages back where the coil is. It's like five pages back where my optic eyes are. But on that page, it says that if that liquid level is open, so now I know I'm running out of gas.
• 1:14
  It has to do with the electrical circuit. The mechanical, I'm low on charge, but my electrical circuit took me there, right? And so, so I know to focus there. Either that relay's bad or I'm low on charge. Just check your, your liquid, your CO2 level and see if you have CO2. It could also, remember, could still be the relay.
• 1:15
  Because maybe this is stuck or this is bad and it's not closing. Although it's normally closed, it's not opening. Or it has open, you know what I mean? All right. So keep these things in mind and then that causes PSC to de energize any one of the, any one of these things causes that to open. All right. And these are just some different alarms.
• 1:16
  This is an over pressurization circuit, which would take the whole store down and we would find that a different part of the of the circuit. But This also is like six pages away. We have to find, I have a coil. That means I have to have a relay point. I have to have normally open or normally closed position.
• 1:17
  All right. So let's go to the next page. There's my pumps. What is the first thing we see on our pumps? DSC1. So I'm using one relay and I'm using one set of safeties to protect two pumps and you, and once you get good at this, then you'll start seeing, man, this is great. And so I'll show you, cause I know we're truncated on the schedule, but I do want to show you something else.
• 1:18
  So if this is clothed, this, everything goes and I energize my motor stators are good and I energized the pump. But when I energized this circuit here, yes. I come up this way on this drawing. Remember, the drawing's a roadmap. It's, it's, it's before we had Apple CarPlay. And so, if this starts, that means it's going to produce current around the wire.
• 1:19
  That current, that magnetic current, Field is gonna be sensed by this sensing, this current sensing relay, which reads the, A magnetic field, the intensity of the magnetic field. That will close to, it's kind of a proof to tell my pump is on, but it's also going to energize this PR one when that energizes.
• 1:20
  Okay, what does that do? I have no idea. So what do I have to do? I have to look at my drawing and I noticed it's a normally closed set of contacts on pump two. So if this energizes, because this closed, because this started, this is going to what? It's going to open. What did I just do? I just locked out.
• 1:21
  Pump two, they just made sure that both pumps don't run at the same time So if I walk in I see this and then I both pumps are running The first thing i'm going to do start looking at pr1 and pr2 Maybe the coil is bad or or the relay pins are bad and i'm actually have both of them closed Maybe it's wire drawn Maybe somebody went in there thinking they were doing one thing and they actually did another thing and so but I can't get there If I don't read this drawing,
• 1:22
  Trevor: right?
• 1:23
  I love it. And that's so important. That's, that's the thing is understand the equipment you're troubleshooting at that moment, and don't worry about what other systems you were at before that new system that you're on. Think of it's the first piece of equipment you're working on. It's just like doing a service call.
• 1:24
  Even though you had a service call that may not went so good before an hour earlier, it's It's a brand new customer. It's a brand new service call. It's new. Take it what you're working at at that moment. And that's the most important thing because this next wiring diagram is going to be different than the next one.
• 1:25
  And like Rusty saying, take your time on this stuff, get into these wiring diagram, because if you don't have this wiring diagram, you're going to spend an hour, hour and a half trying to figure out where do I start? And with this service call, like Rusty would have walked in here within 15 minutes. He would have known that, right, by using his meter, finding out where the power is, where it's open or closed.
• 1:26
  15 20 minutes.
• 1:27
  Rusty: Understanding the drawing, like Trevor just said it, taking the time to really understand you know, Oh, I don't have time. Yeah, you do. Because the slower you move and the slower time you take, the faster you are. To get fast, I slow down, right? Because now I solve the equation quicker and I get to the end point faster.
• 1:28
  So slow is slow, slow, slow is fast. So understand the line, study it. Be the dude. Be like Trevor. Be the dude, man. Be the guy they call because you, oh, well, he, you know, every day I wake up, I want to try to be the dude. I fail miserably, but I try. All right. So, and this just shows his way. Here's a great one.
• 1:29
  Here's on a booster oil system using HB sensors. If you walked in and that's all you saw, would you fix it? Could you walk through the circuit? Where would you start? A lot of times that's the question. Where would you start? Well, if I had this compressor off on a whale and I knew this was my troubleshooting circuit, because I, I understand the circuit.
• 1:30
  Well, the first thing I'm going to start now, I'm going to go through, I'm going to go through the sequence of operation. Normal, then we're going to back up and fix it. All right So the first thing that's going to happen in the circuit is for those of you who've worked on these. This is that hb sensor that that that you use an ammonia all over the place.
• 1:31
  They use these in europe I was just terry and I were both just in chelventa and I saw them all over the place this hb sensor. It's A sensor, but it's a switch, and if you look at it and look at the model number, it says switch. Okay, so I have the drawing here. 24 volts DC. Oh, check this out. 24 volts DC.
• 1:32
  This is the same page. This is the same page. 24 volts DC, 120 single phase, 208 control. Pay attention with your meter. If you don't know how to read wiring diagrams, take the selector switch and put it on auto detect so you don't blow your meter up and it will automatically switch AC to DC for you. But don't be that dude.
• 1:33
  Be the dude that knows. So, here we go. Oil switch. If this is good, that means I'm running, but now I need oil. I'm going to, I'm going to close that switch one to three, passing 24 volts DC to this coil. So the first thing I would start, where, where does the circuit start? It starts with the sensor of the switch.
• 1:34
  So that's where I'll start. Cause we're doing the older operation first. And then what is that going to do? That's going to energize this oil, this low temperature compressor oil relay. How do I know? It tells me it's L2, LOR1. I have to read the language, and so that's going to simply close this normally open set of contacts.
• 1:35
  This is a dry closure. There's no voltage. As you can see here, it simply goes to a digital input board on my controller. So all I've done so far. Is told the controller which one I don't care rdm copeland dan fos microthermal, For for my canadian comrades, right? It doesn't matter. It's a digital closure So then I just told the control dude.
• 1:36
  I need oil the controller says. All right. Well, how about this oil valve control? All right, that's pretty simple. I close that board and point. When I close that board and point, it energizes LTOVR1. When that energizes, well, we already determined there has to be a coil or a relay pin somewhere, a normally open or normally closed set of contacts somewhere.
• 1:37
  And so let's start looking for LTOVR1. Here we go. Pin six flows that. Oh my god. Can't believe it. We finally turned the solenoid on to energize the oil. Any break in the circuit was going to cause an oil failure. A mechanical issue. My compressor's off on oil. Why? Alright, so now let's say I'm coming into here and all I know is my compressor's off on oil.
• 1:38
  Where am I going to start? I'm not going to start at the switch necessarily. I'm going to start at the solenoid because that's what's not coming on to feed oil So i'm going me personally what I do is i'm going to again put my meter on t2 Or l2 and i'm going and even on dc. I put it on the negative part of the dc That's a that's a negative voltage.
• 1:39
  It's not going to be like a neutral or whatever And so i'm going to go on the other side. It's going back to source ac or dc AC and DC greatest rock and roll band ever. Sorry. But I'm going to go. Okay. He's not energized. Why? Where did I open the circuit? Well, being lazy, I'm going to go up here to read a point.
• 1:40
  The board is right here in front of me, the electrical panel. It's right there. So I'm going to pop my meter right here. If I have, this is too late. I'm on T2. If I have to wait here, I'm going to go up here. Which way do I go? I know the controller said go. I know the controller closed the relay. I'm going this way.
• 1:41
  If I don't now I do I have a bad relay is the fuse bad because I check voltage here It could be the fuse on the relay output board, right? That's how I would find it So I have voltage here. No voltage here. No, I have two questions. Is the controller calling for it? Remember is the controller calling for it?
• 1:42
  That's something we get, you know We get all caught up with and we're going to cover that in a minute Listen to what the controller tells me is it calling yes or no? Is it calling? If it is, that should be closed. I probably have a bad fuse. If it's not, then I'm coming down here to see if I got a digital closure.
• 1:43
  Did he, is he energized? Because if the controller's not doing what he's doing, maybe I'll check and see, I'd home across that to see if I had a closure. If not, may check right here. Because the, the, the HP sensor simply did not switch from pins one to two, to one to three, and didn't send that 24 volts DC out to energize the coil.
• 1:44
  So, so does that make sense to everybody? You, you, you just have to think what's supposed to turn on, who's turning it on, and what voltage do I expect to see? Okay. And so when we get there, this looks complicated and this is something I do. I carry colored pencils with me and learned it from the army. Take, and like, if I get something from an OEM, the first thing I do is take out my electrical drawing and I color in my circuits, my black and red wires so that I can see it quickly in my, in my mind's eye.
• 1:45
  And I'm a big person. I think Trevor is too. I'm all about visualization. And so visualize your circuit Think about your circuit easier. I'm telling you, and it's gonna get you ou and it's gonna stop you f this switch, it's reading this way. Stop it. Read t circuit in front of you a mean to make fun because But we really should be reading it here and doing it here.
• 1:46
  I just get good at
• 1:47
  Trevor: The thing that I want to point out is that we as technicians are always putting out fires and things aren't working all the time when a system is running normally. This is why I know everyone should do a startup, you know, do a couple of startups, but when the system's running normally, that's when you should be taking your meter out and going along the wiring diagram.
• 1:48
  So you know what it should look like when it's running normally versus when you go there, you've never been out of the system before, or the only time you've been at the system is when it has had an electrical issue or a problem. If you don't know what it's supposed to look like normally, then it's going to be harder to troubleshoot that system.
• 1:49
  So Start troubleshooting systems that are running already fine and start using your meter, just like Rusty's talking about going across and getting an understanding. Should I have 24 volt DC there or not? Is it open? Is it closed?
• 1:50
  Rusty: I like that. And that's how you use your meter. Sometime when everything's working fine and just do the things we're talking about and see, oh, I get it.
• 1:51
  I get it. Right. You know, you've got time. Harry says we don't have time. You have time. We have more time than we, we, we, we said we do believe I've been in a van. I know what I'm saying. You guys have more time. All right. So if you guys could just hang with me for about another 10 or 15 minutes, I promise you I'll pull this in the driveway.
• 1:52
  Especially for my American friends who were in play last night I'll try to get it. So you guys can go take a quick nap. So this is the high pressure control valve. This one is the ICMT valve. The ICMT valve, it's used in ammonia all over the place. It's used in bigger industrials of CO2. It's kind of being replaced with the CCMT valve, but it's still, there's so many of these things around here.
• 1:53
  And so let's see what this thing does. This is the high pressure control valve. It is the one on the, on the drop leg. I've got 24 volts on the red leg power leg coming into it. Now on the black leg, I have a zero to 10 volts signal coming from my analog output board. On this case, it happens to be a Danfoss one Oh three, but it could be off of an, I think cell controller.
• 1:54
  It could be off of three, 26 a it could be off the microthermal. What is it? The seven 44 V board. It's a valve driver board. They're all. It's an analog signal. It is a stepper. I like to refer this to this as an analog stepper, not a bipolar stepper or a unipolar stepper. And I'll show you why.
• 1:55
  Because coming right here, you see 17 and 18 coming off the controller. That's a zero to 10 volt DC signal coming into these two pins off the yellow and green wire. All right. And so if the valve says, you know, 50%. It's open 50%. I expect right here to read five volts. D. C. If this says 48 percent I expect to read 4.
• 1:56
  8 volts D. C. And that tells me the controller's in charge and I want to make sure because we want to get as we do boosters, we want to get in the habit of looking at where the high pressure control valve is based versus ambient. And so we want to make sure we're getting a good signal. Let me caution you here, though.
• 1:57
  There's a lot of people that are not paying attention to these high pressure control valves. How many times have you heard when you're talking about computers? Garbage in, garbage out, right? We hear it all the time. In order for the high pressure control valve to work properly, not only do I have to have the transducer, that is an input, the pressure input I have to have that set up, I also need to make sure the temperature probe coming out of the gas cooler is not only about six inches out, I want to make, I want to put it about four o'clock, five seven o'clock on the pipe, but don't just insulate it with, you know, You want to put thermal paste is awesome, but then wrap it with Rubitex, but then get you a little piece of vinyl PVC wrap.
• 1:58
  Live in, what if you're in Miami? You know, it'll, that Rubitex will break down in six months. And now I'm not protected. That temperature sensor is very important in driving this high pressure control valve. So, so that's what we're We're talking about electrical, but we got to talk about our inputs as well.
• 1:59
  So make sure you got a good input now Let's say the high pressure control valve's geeking out. Here's a little trick. I have went online. To amazon. I bought me a 0 to 10 volt small little 0 to 10 volt or 4 to 20 I can switch Signal generator. So if I'm not sure, is it the board or is it is it, is it the controller or is it the, the ICMT itself?
• 2:00
  And I can take the wires off of the, the 326, the iPro, the Dixel, whatever it is. And I can hook my zero to 10 volt meter up and I can drive the signal manually. And I should see that on the face of the ICMT. And if I can do that, I can say, okay, from pin 17, 18 on my drawing. To here. I'm good. So that takes me back to the controller that takes me to the wiring of the controller And so so that's some things I think about how do we use better tools smarter tools to help us cut the problem in half Right if I have voltage here if if I hook my signal jamming nothing happens i'm going to focus here on the wiring or the circuit board.
• 2:01
  There's a circuit board inside of there underneath the cover and it may be simply the circuit board burned out. All right, so I'm going to come here. This is the flash gas bypass valve. These are bipolar steppers real quick. I want to go through bipolar. Bipolar valve simply means, you know, we all know how many steps I don't care how many steps I really never do care because a step is is a predetermined movement By when I hit when the controller the ipro whatever sends a signal to it It's a predetermined amount of movement that I have on the rotors in the state of the stators to move that valve Positively or negatively right?
• 2:02
  And so so all the step means is the predetermined Unless I'm programming. If I'm programming, I care. But as a technician, I just want to know if it works. Right? So I don't care what the steps are. I don't, I'm not, I'm not there to, to, to redo. There's like 10 guys in the field that can really understand PID.
• 2:03
  So if you're not that guy, Vpid alone. Let's look at the voltages. It's more than voltages, but let me show you this This is something I find really cool and you guys can do Well, of course we can take if we think the valve is bad We can take each winding to ground make sure it's not shorted. We can make sure it's Not open by using our, our, our own meters.
• 2:04
  But if the rack is running and you don't know if this thing, you think, and I don't know if it's the Dixel, the 326, I don't know. And you can take your meter, put it on DC. Then take your leads and go to the white and black wire. We're all using white, black, red, and green. That's just the standard. I put my meter here.
• 2:05
  If the valve is energizing, working properly, and my controller is sending the proper signal, I'm going to either see somewhere between minus five and minus three volts DC. And every time that valve moves, I will see it switch from negative to positive negative three. Positive three negative three positive three.
• 2:06
  Now, sometimes it will go positive if I'm close to set point. It's not going to send a signal. So I'm rarely going to see that move. And so if I'm suspecting this wrong, I can simply go into the control or change the set point so that I can force this valve to drive to a new position and I will see it go negative three positive negative and maybe minus four.
• 2:07
  Maybe Negative five, whatever. But I can see it moving. And then I take my lead back to the red, green and red, and I, I want to replicate that. I'm going to see the same thing. And if you've never done that, and you're at the rack, next time you're at a stepper valve, try it. It works with the CCMT, the CCM, who works with SCRs.
• 2:08
  I do it all the time just to prove my theory because it's something you want to see. But think about it. Every time it steps, It's got a signal signal and you can read that signal with your dc meter. All right. So, so that's just a really easy way to troubleshoot and determine if it's the output board, the tool to awaits or the for a board.
• 2:09
  Is it the 2 0 8 C board? What is it? Okay. So, and those that's my favorite not to the high pressure control valve. Look at this. Do you know that this is online? It's called the internet. And if I pull that down, I can take one of those needle leads. Everybody got the needle leads you put on your meter real thin.
• 2:10
  If I put my needle leads on D and F, D and F. So there's a key way. So I would hold it and look at it, put my leads there. Whatever's coming off the controller, DC wise, voltage wise, 4. 5, whatever it is. , I can see that on my meter. I just proved the wire. I proved the controller is good. The wire is good.
• 2:11
  It has to be the circuit board. There's nothing else that can be right. And so look at the things and look at some of these things. And when you see these kind of cable plugs, if you go online, you can find this kind of information. And dude, I'm telling you, this has helped me two or three times. We've condemned, we've condemned two and saved one by using this cable and reading it through here.
• 2:12
  Trevor: Some of the manufacturers as well as they, if you've got a big industrial rack, it could be 40 feet, you know, and sometimes at the manufacturer, they only have 20 foot length of wire. And so sometimes there's splices. So what Rusty just said there, and I've seen it multiple times that you got to check that wire because that could have been wired.
• 2:13
  There could have been a splice in one of the wires going back to the board or the signal wire or the zero to 10. Our job as technician, not to get mad at the manufacturer, whatever happened at the factory is going in and verify. Are those points exactly is the resistance there? Are we getting the right voltage?
• 2:14
  Resistance? Whatever you're looking for because that stuff does happen, especially with electronics when you're doing Runs of a hundred foot to electronic valve not only for this one
• 2:15
  Rusty: that because you see these butt splices when they put a butt splice in, you know, I never could figure out why you bust place a white wire to a green wire, but what happened?
• 2:16
  He's not my place to judge. As Trevor said, it's our job just to figure it out, cut it out, fix it. Add another add another 30 to the invoice. Just for observation. Don't do that. Don't see what she said to do, but here's the same thing that I just said. Just kind of a bigger set. This is using a CCMT valve.
• 2:17
  Doesn't matter. White, black, red and green. It's the same thing. It's just like when we're using our SMA 12. Don't forget your SMA 12. You can use the SMA 12 to drive these. If you're not sure if it's driving or not, just put, hook it up to your Sportland SMA. By the way, give Sportland a plug. They are coming out with a new one with a unipolar.
• 2:18
  Danfoss has one. I'm fixing to make my own. I just got one of the guys at CoolSys sent me some parts and I'm going to make my own, but use those tools. Danfoss makes one. Use a stepper valve driver. We are going to be ate up with electronics. Electronics are not going away. We're going to exponentially, we, we're almost going to have to be electrical engineers.
• 2:19
  So, so we have to get better tools. All right, real quick. And let's finish with this. And this is a If I have time, hopefully I can get to that. This is this is not good. All right, if you do a micro thermal maybe but everybody Wants a daisy chain Modbus signal. That means if I take this point in this point and I pull them, it's a straight line That's how I know if it's a daisy chain or not do that in your head You can go all over the place, but you have to be able to grab both ends and stretch it All right, so everything's being daisy chained, right?
• 2:20
  I keep saying the Mechanical Expansion Valve is going the way of the Dodo, because I can't log into a Mechanical Expansion Valve, and everybody, everybody wants to Bluetooth, everybody wants to dial from Washington State into the, into the rack in Miami, right? I'm going to be in Calgary and I want to look at the thing in Quebec.
• 2:21
  It's just the way it is. So just keep that in mind. So this, this is important. We have to make sure we understand it. And so here's some modern tools, you know, with Modbus, we're all used to going and going center to positive center to negative reading 2. 4, 2. 7 volts. We're all used to troubleshooting it.
• 2:22
  Like how many times have you been here? Something's going offline and One guy's on one end and you're at the controller and he unplugs it. Good. It's on. No, no. Good. No. The other one went off. Okay, wait, here, I'll put this one. No, I went down. They said this dude, which one? Okay. The all off now. What the hell?
• 2:23
  We've all been, I've spent two days trying to find my bus, looking at every single wire and make sure one strand isn't touching. We've all been there. That's so last year. Let's get better. So I want to introduce you to two of my favorite tools. This one is a intensity meter. It reads the intensity of a magnetic field, kind of like an app probe, but check this out.
• 2:24
  It reads in micro Tesla's. Why? I don't know. But you can see it's red. I'm reading 290 micro Tesla's. I've got this is my mod bus for a crow controller. This is a U. S. B. This is a mod bus to U. S. B. Converter and they keep dropping these things offline. Nobody can figure out why. What do you see right here?
• 2:25
  One two, and there's two more there's Trans they ran it by the transformer transformers are hit up with magnetic induction magnetic field So they're running straight through the magnetic field and if we look at our oscilloscope, which we will I would see all this noise So this is a nice I paid 15 for this one nice little tool amazon, But here's my boy pikachu This is my oscilloscope.
• 2:26
  Used to use these in the army. He's small. He fits in my backpack. I have a pokeball for him and Here's how he gonna work. So here's Pika. Here's Pika have a cable that goes to my laptop. When I bought this, it has software. This software is going to give me a DC signal.
• 2:27
  I'll show you that. And I'm going to the square wave. Remember Modbus is a voltage, a DC signal. We know that because it says 2. 6 and 2. 4 volts DC. All I'm going to do is read that DC signal. Then I take my probe. I come up here to my controller. This happens to be a crow boss, but I done it with Emerson. I do it with Dan Foss.
• 2:28
  Excuse me, Copeland and it works Modbus or long. I can do this with micro thermal as well. But what I'm going to do is put these, my meter leads in series or excuse me, in parallel with my Modbus signal. And so what I'm going to see is if I run this, this is a beautiful square way. Notice the amplitude makes sure you see how it's transmitting.
• 2:29
  Matter of fact, if I hold my laptop up to my, my Controller where I have that TX and RX light that's flashing that will flash at the same rate. And so that's a beautiful signal. And so if I go here, that's a horrible signal. The amplitude is too low. There's no transmission and no receiving. So what did we do with this?
• 2:30
  I want to go quickly on here. We took, this was on 40 cases on one Modbus network. The first thing we did, 40 cases. How the hell we're going to troubleshoot that? Well, what we're gonna do is disconnect. Go case 20 and disconnect 21 through 40. As soon as we did that, the signal came up. We were good. So we just said the 1st 20 cases are good.
• 2:31
  So what we did, we added five more cases. When we added the five more cases, the signal went So we knew the problem was between 21 and 25. Then we broke it in half again. We were able to within 40 minutes, find a broken wire in conduit on the Modbus circuit. In 40 minutes, 40 minutes, broken wire on to it.
• 2:32
  So these let's get smarter, use better tools, be smarter with our smart tools. Matter of fact, if you buy one of these, I have, I have three subroutines I use. I've already preset up. If you send me an email and a hundred dollars, no, you send me an email and I'll send you my subroutines, I'm trying to give it away.
• 2:33
  And then one last thing. Promise. Remember when we're looking at refrigeration and racks and supermarkets and industrial, it's a marriage. It's a marriage between the piping, the electrical, and the IO list. I cannot troubleshoot a system without understanding the three of them work together in concert.
• 2:34
  All right. They have to work in concert, and I just want to make sure everybody's aware of that. And we have to close that loop. And can I, do I have time for one more quick story? Yeah, let's do it. Let's do it. All right. So here's a primary, that's a case controller. Notice these are normally, these are Form A contacts.
• 2:35
  The controller closes these relays. Okay. So I want to tell you a place of You're a failure on my part. I was so depressed. So I taught a class on basic alike and I left that class and I'm like, I am cool. I knocked it out of the park. These dudes are ready to go. You know, I'm like, how? And so that was Tuesday, Wednesday, we go into the store for some practical and we walk in and one of the cases.
• 2:36
  Lights are off and this is what I mean by a marriage And this is what I mean that we have to connect we have to close the loop We have to think about critical thinking we have to process this. We we can't just look at a widget I can't just look at this piece. I have to look at the whole And and here's why so we walk in and I go.
• 2:37
  Oh look Case lights are off on case one, an open deck, a multi deck 12 foot case. Yay! Let's find the why the lights aren't. And we walked up there after a week of electrical, the first thing they started saying is, Huh, I'll bet the motion detector's open.
• 2:38
  Right. I'm thinking in my head,
• 2:39
  dude, that's not what we talked about. I said, I said, okay, before we do that and try to troubleshoot anything, we don't know what's going on. So it's a Bluetooth case controller. Let's Bluetooth in because Bluetooth is cool. So we Bluetooth into the case controller and we're all in a group. There's like ten of us.
• 2:40
  We're looking at it. And I go through there and I go, oh, look, let's go to the digital outputs. We went to the digital outputs on our phone. And the deal, the digital output said lights off. Okay. So our original question and problem was why are the lights? Why is the electrical circuit not turning the lights on?
• 2:41
  But once we saw the controller set off the question and what we're trying to solve changed. Now we want to know. Why is the controller telling us to be off two different questions with two different answers, right? But, but I said, Oh, look, the lights are off. It's a Yeah, I think it's the motion light. No, no, no, no, no, it's not the motion.
• 2:42
  What about that relay? Somebody get a meter. Let's check the relay. What relay the relay out here comes into the box not the one on the control? No, no, dude You can if you may find something but as long as the controller says, ah Not those lights will never come on Right, and I realized the disconnect I taught him the piece, but I didn't teach him the whole solution Right.
• 2:43
  So when we think about electricity and problems understand, it's not just the widget It's not. Oh, it's a quick guess. Next time. One of these days, I'm going to go to jail because one of these days, one of you guys are going to start to guess. I'm gonna hit you in the back of the head. It'll be a small person, not a big cut because they'll beat me up.
• 2:44
  But make the connection. What the problem was, it was an easy one. The case was the case gets a signal for the lights from the building control system and has to get a signal from there to turn it off. You need to understand what's in your store. All right. And they were, they, if we weren't there, I wonder how many days they would have spent trying to figure out.
• 2:45
  But the controller set off the controller told us what the problem was. We didn't listen. We didn't listen to our components All right, and so I just I hate to preach. You know me I get a little preachy. Love
• 2:46
  Trevor: it That's the thing though. It's like Refrigeration is facts Electrical is facts There's no assuming when I learned that it took me a long time being in the field for a long time and supermarket application construction service startup.
• 2:47
  When I learned that I started to learn that do not assume in refrigeration, find the facts out. That was when the game changed for me. It's facts.
• 2:48
  Rusty: I promise you this, gentlemen and ladies, once the light comes on with electricity, it is one of the coolest endorphin rushes that you're going to get. It just did.
• 2:49
  And so I encourage you to You stay on it and study it, read the wiring diagrams and rock on.
• 2:50
  Trevor: And this is what we do here at refrigeration mentors. Bringing the experts from all around the world, Russia from NSARC. Like I said, this is what we want to do. We want to uplift the industry. We want to help you become better and share this knowledge.
• 2:51
  So what we're just. Talked with you about here. I want you to go and start training this stuff with somebody on your team Somebody, you know talk to your wife or spouse or your husband about it Whatever start talking about this more get into these wiring diagrams Just like rusty me me and rusty have done this dozens and dozens and hundreds and hundreds of times and we're still learning We're still learning about this now, we want you guys to do that too rusty I want to thank you so much for taking the time How can people find out a little bit more about you where they can find you?
• 2:52
  You can
• 2:53
  Rusty: find us on nasrc's website Or you can email me at rusty. walker And check on our website. We have training summits going all over and we do come out and do training. But we encourage you, I know Trevor spoke and we were really happy when he comes out at our different training summit. We got one, anybody in the, in the, in the West, we have one in Seattle next week, and I encourage you guys to come and visit us let's, you know, and let's quit, give one more plug, quit saying HVAC and R.
• 2:54
  That's not how it's supposed to be pronounced. It's pronounced R slash HVAC.
• 2:55
  Trevor: No, it's not. It's pronounced refrigeration dot. Drop the mic. Mike. Yeah. I love it. Rusty. And like Rusty said, get out to more trainings. You're here learning today. Tomorrow. Get another train next week. We got to continue to learn.
• 2:56
  This is what it's all about. Continuing education, uplifting the industry. Thank you so much, everyone. And I look forward to seeing you at the next CO2 experts live. See y'all.