Irrigation Electrical Safety

February 27, 2024

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How do we safely operate electric pumps and center pivots?

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Video Transcript

For the participants that have entered the room. This is the Michigan Ag Ideas to Grow with. We're going to be talking about the irrigation electrical safety. It's always been perplexing that we do irrigation with 480 volt electricity. That's our primary source of energy and the most efficient systems we have. But we still have water and electricity together, which always ends up being some kind of a safety factor. That's why we get people that are really smart and can handle electrical issue. Right now we try. Good morning. On behalf of Truman and I. It's a pleasure to be with you today for this segment of the Michigan Ag.\ Ideas to Grow With - Water. Irrigation systems have rapidly grown in Michigan. Changing rainfall patterns, risk mitigation, and expansion of seed corn production in Michigan. With establishment of two of the largest seed corn facilities in the southern area have accelerated this growth. This growth has resulted in a rapid increase in the number and size of agricultural irrigation systems, sometimes stressing the local energy supply. We can now boast of St.Joseph County, Michigan as the most irrigated county with the most center pivot systems east of the Mississippi River. This growth has necessitated the need for stressing electrical safety to prevent accidents that can sometimes be fatal. You see the red spots there. That's where a lot of growth in terms of number of irrigation systems and where there is energy stress. Right now, some areas, especially the southern areas of Michigan utilities will not allow you to increase your size of your electric motors or add additional pivots because there's no more juice on the line. To that effect, we have informed Michigan Public Service Commission and Utilities, and Truman has been doing a great job in explaining this to them. The Michigan Public Service has approved a new high voltage transmission line. Forgive my drawing there. That line represents where the high voltage transmission line will traverse. And as you can see, it is traversing in this energy stress area. Hopefully, that will make things better. However, implementation of this construction start will still be in five years because there are other processes to get this project finally approved. An irrigation unit, such as a center pivot system, is an electrical challenge, in that the electrical current must be transported over a long distance. Some units can be up to half mile long because the wires have resistance. Voltage drop will occur as the current travels this long distance from the source panel to the individual segment motors or other loads, be it a high pressure or low pressure sprinklers. Large electric gate driven irrigation systems generally require three phase power at 480 volts. Although the control and drive components generally operate at a much lower voltage at that voltage level, the effect of electrical accidents can be significant, in some cases, fatal. Three phase power is not always available to most farms or irrigation locations. There are challenges in those situations since utilities usually do not allow electric motors greater than 25 force powers in single phase lines. Okay, this is Truman and I'm going to try to give you some overview. What I want to talk about here first is give you a little bit of an idea of some of the background system and then we'll get into some of the issues of how to deal with some of the safety issues. And of course, lightning protection is one of the big issues to deal with when you don't have three phase Power available. You got to somehow across the state. Some of the people have been a little bit innovative and how they can operate their irrigation systems. We have a large amount of power required for the pumping. And then it doesn't take all that much to be able to actually operate a center pivot situation. Just to give you a quick overview, for example, here's a situation where actually they have irrigation. But it's not at this particular location. They were lucky to be able to a few years ago to get three page power put in. But this is a single page situation. In these cases, the highest voltage you're going to get is 240 volts. Now, here's the typical situation to where you have an electrical line. If you'll notice coming into that, if you look at the very top, I guess I can do that right here. There's actually three electrical wires coming in. They have 33 phase power. Now, in some cases the transformer may be ground mounted, but in other cases it's going to be up on a pole, if you'll notice in this situation. However though, the power is moving from the very top here, moving in this direction. And if you'll notice this one right here, there's only one, actually two, what we call ungrounded or hot utility lines moving on beyond that point. Beyond that point, typically it's a little different situation to be able to get electrical power, and I want you to be able to understand how that works. So let's take a look at that situation. Now, in this case, this is like the substation would be off here to the left. And notice that there's three wires across the top. Those would be the hot wires in Michigan. In some cases, they run at 4,800 volts to the ground. Everything is grounded. And that's important. We'll talk about that a little bit later, why that's so important. But between that and the Earth, in this case, we could have 4,800 volts. We could have 7,200 or another common one is 14,400 volts, which is double the 7,200 It just depends upon which one of those situations you have in your location. Typically, in the East of the Mississippi River, utilities are running three hot wires, a neutral, and all those are used for a typical installation. If you move down to the next pole, for example, there's all three wires there, and if you look on this, there'll be three transformers that are on that pole. On the previous picture that I actually showed you, I told you in one case there were three wires. Hot wires. And if you look in this situation right here, this is like I showed you in the previous pictures. There's only two of them. So what do we do in that case? Three phase power is still available in a situation like that. It's hooked up in what they call an open y primary situation. But for those of us on the irrigation side as the customer, we call that an open delta. If you look here, there's only two transformers. If you look back at the previous pole, there's three. We can only have two because there's only two hot wires, we can still get three phase. The problem here then if you move beyond that situation, it could be down to single phase. In a typical customer, it only has single phase power, has one hot wire. This could be anywhere from 4,800 here in Michigan to as high as 14,400 But their transformer, if you can see way over to the right here, is connected between this hot wire and a neutral wire. That's typically how things work pretty much across the eastern United States. Okay, so here's another close situation of that. The one on the left here, for example, is how we hook up a single phase power. You've got a hot wire up here and it comes through, there's lightning arrestors and fuses and so forth. But then there's a neutral wire, the utility neutral wire. And it's only required those two wires in order to be able to get single phase over to the right. For example, is that we actually have three hot wires on the utility and a neutral wire, and those are all used. Use, and we're using three transformers. If it's a ground mounted one, all the windings will just be in one case and all put on one transformer core. Okay, so here's the case then, just another close end view of a typical three phase if you have all the wires available. What I'm driving at here is one thing you may have to look at is if you only have single phase, what are the chances that you can increase that to three phase? But just take a look at the electrical line that's in your area and where the power is coming from and follow the wires back. Is it very far before you see at least two hot wires and a neutral? Or in some cases, you may be getting back to where there are three hot wires in the neutral. If you've got two hot wires in a neutral, then more than likely you're going to be able to get three phase power. Then it's a matter of talking to the utility about whether or not they are able to extend that power to your location. You're going to have you irrigation and whether or not there's going to be an additional cost of being able to do that. One of the problems that we have, irrigation is sometimes the pump location, and that's where the major power is used, is not close to where the power lines are here. On the left is a situation where we have an open delta. This is what it looks like, there's two transformers on that electrical pole. If you look to the right though, this is how it looks. You can operate what we call a delta three phase system with one of the transformers missing, so you can still get three phase power. I wanted you to understand what the availability was to be able to get three phase power so that you'll know how to look at the situation yourself and see how far it is you'd have to go to be able to get three phase power available. You can also get it with just the two wires for example. And then you'll have to contact the utility and see what can be done if you're stuck with having to work with single phase power. Some people have brought up the issue about what we call a phase converter, taking single phase power and working up the three phase power. Now, this is a busy situation, but I'll show you the important part of this. This is not a practical application if you're going to have to run power to the electrical pump for the water, because that's going to be a pretty high horsepower, you can probably use a single phase phase converter. But I think in most cases, if you're working, you're drawing all your power off of the single phase line. Here it shows here to the left. This is a single phase panel. Here we're stepping up the voltage to a higher level because we really need 480 for this one. This is single phase, the 480 is single phase. And now we're coming into the phase converter. We come in with two single phase wires. But this apparatus at the bottom, which is a rotating transformer unit along with a bank of capacitors, is going to create the three phase pole that's practical for running the machine. Because even one of them that's fairly long. If you add up all of the motors at the individual drive locations, you're probably not going to add up the much more than about ten or 12 horse power. Because those motors at four 80 volts have got an awful lot of power to them. And that's pretty practical, a phase converter installation. So now you see down here we go, this is the actual controller for the machines. In this case, it would be feeding the, the center pivot itself. And I think that one of the pictures that Al showed you actually had a situation like this at that center pivot point. When I was watching what he was talking about. I want you to realize that this is basically how it works. There are those people who think they can build these themselves and all they do is ask how many capacitor as well. I don't recommend that, especially with the cost that you've got in the system. You need to go to a manufacturer who handles and what you're asking for the rotary phase converter because it has more flexibility in being able to work. And this has to basically be matched pretty close to the load that you're going to be using in the in the center pivot unit. Now, what if you're stuck with single phase power at your pump location? Here's a case, there's something that was developed a few years ago that works reasonably well. You got to work with utility though, because this one right here is 60 horse power, which is probably in the range of what you could get by with this one's over, I think in the western Michigan and it's what we call a written full motor. So that's a special motor made to operate with fairly high power to be able to put on a large amount of power. Typically, single phase motors go up to about ten horse power, and that's it. Anything beyond that is made as a special purpose motor. For some cases, a written pole motor is probably an application if you don't have another, if you don't have only single phase, here's another, a clever installation. I think this also is over in the western part of Michigan. And this is the case though to where they're running the whole system off of single phase. There's another 60 horsepower written pole motor. But if you look at it, notice that right off the end of the motor there's a belt going over to another device. This is a three phase generator. This generator is going to put out three phase 480 volts. But down here you can see the pump on the same shaft. In this situation it's providing the power for the pumping purposes, but it's also siphoning off about ten horsepower worth of power in order to be able to turn this generator in. The generator is providing the power from the center pivot unit. There's another application to where people have been pretty clever and have been able to work things out. This is just another application and maybe a different angle of it. There's the large written pole motor. It's running a generator which goes to the center pivot unit and then the shaft is also running the pump out here. Again, it's operating off of a single phase line. You got to work with the utility because when that motor gets started up, it's going to create line flicker for all your neighbors. And that's one of the reasons to why the written pole motor is sometimes work. You got to get it up and running and then you can start adding, you might need to clutch in the pump and so forth after the motor is getting up the full operation. There's ways in which you got to work around that to a system like that work. Here's another a side view of the same thing. We're coming off a single phase. It's running the written pole motor and that written pol motor right here. It may be then running the pump which is not shown on the other side there, but it's also running the generator to handle the center pivot irrigation machine. There's different ways of looking at it. So those are some of the background that we can look at and hopefully that may help you a little bit. Weld, get questions, think about them a little bit and ask those questions of me later. And I'll see if I can answer them for you. This is a, over the years, Al and I've done an awful lot of work with irrigation. We did a lot of work with the Hookst University of Nebraska on various issues and so forth. And I borrowed one of their pictures here to talk about the safety. Let's look at some of the safety issues. Part of it is going to be safety for people that are working around the equipment, and then we'll get the lightning protection. Let me talk about this a little bit because I think a lot of people don't really understand the importance. Of some of the safety devices that get done with the wiring system. If you really need to have a licensed electrical contractor would be able to do these hook up because they're not the kind of thing that those of us who may not have a lot of experience will be able to handle up the situation. What I'm showing here is of course, just a motor is a device. The same can be done with cattle. This could be a cow, or a horse or something instead of a person. The same situation is going to occur. There's resistance in a person's body. There's contact resistance. When he talks of that, there's the contact resistance that may be high or may be low. You stick your hand down in some water for example, or your hands are wet, this is going to be low. And then there's the resistance through the body because if you're going to take a shock, usually it comes in, gets under the skin, then there's soft tissue under the skin even with a high voltage shock, where lineman or something like that may accidentally get hit with that. Most of that current runs under the skin and the resistance is fairly low through the body. The most of the resistance is right at the entry point. Your skin, unless it's really wet, is pretty good insulator. But once you get through that, for example, all electrical systems are grounded. Even at the utility, everything is grounded. And that has to be that case, or else we're going to have trouble with lightning protection. But then also, voltages can get out of hand with a normal operating system. In order to be able to have stable electrical voltages, we got to reference them to something. And seeing lightning, for example, it's between Earth and clouds, for example. Most of the time. Then the Earth is I guess, probably the best thing to use, Asian ground, but between a person feet and so forth. There's also what we call contact resistance. Take the situation of cows, for example. Horses or any pigs or some other kind of an animal like that. They're walking around sometime in sloppy ground and they're making direct contact. Most of us are walking around with shoes or boots that are not very conductive. So that means this could be so high that you can touch something. You don't even know that it's a bad situation until somebody walks up, maybe barefooted, touches it, and that's a very bad situation to occur. Okay. So here's another one. I, I, I tend to use pictures that I've made up, so a have to just sort of take that as we go through this. I get a little clever at times with my diagram, but here's a case to where the thing I want you to show you about this one is frequently people don't see the importance of equipment grounding. And that means it says, well, it runs just fine with the hot wire. With the two hot wires. So what do I need to run another cop of wire for? Because if you don't, then this person becomes the ground if there is a problem in that piece of equipment. And you can see, I've indicated that you probably shouldn't have a smile on his face. Okay. So in this case then in the current is going to come through the person into the Earth and find its way back. One thing to keep in mind about electricity, and that is you can have a fluid going through a pipe. And if you get a league of a pipe, like your irrigation system, for example, you just got a big mess in one location. In the case of electricity, electricity has a source. In this case, the source is the utility transformer supplying the power. Everything that goes into the Earth doesn't go into the Earth to stay. It's trying to find a way to get back to that mid grounding point. With all these transformers, there's a few applications that might not be grounded, but most of them are the current is trying to get back to its source, In this case it's the secondary winding on the transformer, it's only using the Earth as a path. When we were talking about stray voldage to farmers many years ago, we had to explain to them current can go into the ground, but it also is coming out and sometimes it makes a bigger problem when it comes out of the ground. But that's another issue for another day, that Vogue look here though, we've connected up a green grounding wire. And it goes over. And usually it fastens to the point here to where it makes contact to the neutral lug. In some cases though, there's very likely, could be a separate grounding lug in the disconnect the panel. But what happens here is it doesn't guarantee that there isn't going to be some voltage maybe going through the person to where they might be able see a tingle. But almost all of the current is going this way. And it probably will blow the fuses or strip the circuit breaker. There are cases to where it won't draw enough current to do that. And those are the dangerous ones because somebody can walk up, put their hand on something, and that can be a bad situation. Okay. So also two is we got to be careful about how we're putting wires and stuff into the ground or running them on the equipment. The, in many cases you've got a cable of some kind and that's basically how the three phase power is going down through that power line. Or excuse me, down through the center pivot irrigation because you've got to get power to the far end, 480 volts doesn't take a lot of current to run those motors. If you're Volvo, if it's half the voltage like 240, you got twice as much current. If you double the voltage from 24480, you've only got a half as much curve. The result then is you want the last motor on the system to get pretty much the same current as the first one on that irrigation unit. And the only way to really make that happen is to kick that up to 480 bolts. If you have to run like power over to the pump location if it isn't really close and you've got to run underground a while, you can get underground cables that are direct Berry But I any recommendation I've ever made is if you can run those in plastic conduit and it's PVC conduit is probably the most common one and there's less likely to be a problem that's going to occur. And I'm a little I'm a little nervous about putting aluminum wire down because aluminum can all it takes is you got a lightning strike and you may have some little pinhole weeks ending up in the insulation. And that will leap water in and you get a little bit of water seeping into the aluminum wire and it'll code and it'll turn it to a aluminum oxide powder. I've actually had to dig those up and actually find them in long runs. And then sure enough, when you open it up and you get it out, you can find the point where where that occurred. And it isn't wire anymore, it's just turns it to a powder. So anyway, so going underground, my preference is to pay the price to run copper, although copper is getting really expensive now. Okay, so here's a typical situation where we've got a Y. And this is usually the situation, it's usually what we call a y connection. And it has a grounding in the midpoint for this because you don't need a neutral wire unless you do. If you need a neutral wire, then it's available to run equipment inside of your control equipment that would be at that location. This center point right here might be your neutral. In this case, I've shown it only being used as a ground. It's important, especially at these locations. The electrical code even requires this. There's a spot in the electrical code that deals with center pivot and other irrigation systems. The point here is that you need ground rods in this location. I'll show you another diagram in a few minutes. But it takes at least two ground rods to be able to deal properly with this situation. There's a typical situation to where we're running power to that. The other issue is lightning protection. And out on that center pivot irrigation system, the ground rods are mainly for. They're mainly for lightning protection. Lightning is kind of strange. A few years ago, I had to look into this situation and I found more facts and so forth. And I thought I wanted to some researchers out west. I think there I don't know if they were from the from Colorado or not, but they were up on high ground in Colorado. And these guys were tempting the lightning to strike a certain spot and they wanted to see what was going to happen. Sometimes it was to test equipment, and they wanted the lightning to hit that equipment to see how it worked. And they would measure what we call the electric field in the air. And that's something called, it's volts per meter. I can't remember the level that they would monitor it when a lightning storm was coming and they were hoping that it would come over that particular spot on that high ground. And that when it got above a certain level, they would, they would launch a wire being pulled by a little rocket and shooting it right up towards the cloud, hoping that, that it would hit that. And if it did, then it would follow that wire down and hit the spot. So it was kind of interesting to see the kinds of things they did. There's another one of the diagrams. I get a little carried away with diagrams sometimes, but it keeps everybody's attention going. So here's a situation about lightning. A lot of people don't understand what happens. One of the colleagues that I work here almost got hit. He knew what it was, even though it was wet, muddy ground. He hit the ground fast, and he did that bang right beside him because he could feel, he could feel the electric field. When a cloud, usually most of the time the charge is in the cloud and it's usually negative, although many times a portion of the cloud is the lightning strikes between two different locations within the cloud. But oftentimes, this voltage may get high enough. High enough that it begins to, if there's a negative charge up here down in the Earth, it starts to drive the negatives away and this becomes a build up of electrical charge. If you look at this tree over here in this barn over here, notice that I've got what we call, these are called, there's some coming down from the clouds probably in several locations. And then there will be feelers going up from other locations as soon as one of the contact is made in these two locations with the tree over here in the barn, there wasn't they didn't make contact, unfortunately, right here is where the contact was made between the one moving up and the one moving down. And as soon as that happens, bang, you got the lightning strike. And it may be a single where it may be multiple and it could be several of them, right? Almost within a split second. And you've probably observed enough of that. You can see this is why it's really important because we're out there exposed with no tree. Basically, it's just clear open ground and this is a good target with that metal and so forth. The electrical code actually requires two ground rods driven eight feet into the ground. The wire going out to them has to be smaller than a number eight copper wire. Even a little bit bigger would probably be better. And so this is extremely important and I would, in my case, ground rides aren't that expensive. You may think they are, but they're one of the cheapest parts of the thing. You can go anywhere, any place and pretty much buy those that are hardware or some of the supply stores and so forth. But I would actually probably drive a few more of them around this location. So you get a good ground because that means then that you'll be able to get a strike on your expensive equipment. If it's done correctly, it should be able to take that with no or minimum amount of damage to your expensive equipment. So try to try to protect your investment from that situation. I think this is pretty much the same as I had before. This is being run at 480 volts. I'm looking on here to see the grounding is going to be done at your main disconnect for the three phase power to your unit. So if you're running three phase power out to that, this transformer may be there. Or it may be some long distance away from it because you might have had to run underground, away with this wire. Because trying to get the utility to run their high voltage wires over to where your pump may be can get a little expensive. Some of you have been clever and some of you be able to talk soft enough to the utility that you've been able to get a break on that. My brother pulled that off. He's unfortunately now deceased, but not from this. But he was able to get the utilities to do quite a bit for his system and so forth. He had, I guess, the magic touch. I wish I had it. There's another device that's required at these locations. In fact, this device is, device is required on almost all disconnect devices, even there even being required for dwellings. This is what we call a surge protective device, PD. The kind that are used outside to where they're exposed to lightning and so forth, is a type one SPD. It's best to put these outside someplace and notice that they're connected in before the puss because you don't want those to blow. You want this to be in the circuit all the time. It will take that lightning bolt that maybe it might even hit some of the electrical line. It doesn't have to be a direct hit to the electrical line. The electricity is generated by a magnetic field. A magnetic field is created by, you know, at the generator. And it's what makes the three phase power that we're, that we're using. And so when a lightning strike occurs, it can be as much as 100,000 amperes. And you hear the bang of the thunder. And we know when we see the lightning and the bang, at the same time it was closed. Okay? And I think you all understand that. But around that lightning strike is a magnetic field. And so if that magnetic field is close to the electrical wires, even the overhead wires or wires between, I had this at my place between my house and my barn. It didn't hit the wires, I don't think. But it did a lot of damage to the electrical system. But fortunately, I had all kinds of grounding and it saved me from a major amount of damage because Well, anyway, all I know is this is just this is just was a 240 volt line going from my from my house, speeding, So outbuildings. And it was a 300 foot run to get out to those to those outbuildings. And it took a lightning strike and the damage was minimal, but I had a lot of grounding along that every time I had a pole. Because I wanted power there so I could use it to take care of equipment and so forth. And I put a little bit of a panel there, but I grounded it. And every one of those poles basically had to ground rods at it because it was supplying power for some other purpose. And all that grounding saved me from major damage. It probably would have come into the house, but fortunately, it didn't do any damage in the house. So I want to stress the importance of grounding and don't be skimpy with it. And if you think that you don't have enough, add another one. It's not that expensive. Now, here's a close up PD. So if you look on this one, this is see it right here, PD type one. This is made, this one's made by the, and this is on the site, This is a center pivot location. Of a, for an irrigation system. So there's a spot down there that they can bolt it on. And it's set up and its purpose is lightning protection, to try to save your equipment. If you've had problems in the past and your system was put in a number of years ago, see if they had one of these. If not, you're going to add them, okay? Because they're there for lightning protection. I recommend that you have those available. Okay, We're getting, I think we're almost getting down to the end here because I want you to know that. Just wanted to show you a little bit about ground current when you put in a lightning rod. Keep them far apart and don't put them close together or else it's useless to put them in the ground in the first place, the second one, because their effectiveness to act as a transfer of the current from the rod into the Earth occurs within mostly. Well, the electrical code says the distance between these two ground rods need only be six feet. But I've done enough work with working with ground rods and their effectiveness over the years that I found that ten feet is better. Anytime I've ever put them in, recommended them going in for a pharma application, particularly, we've just connected them together. This is the farthest one out, and here's the one closest. And then it goes up to the connection to the electrical system. I just want you to realize is that the effectiveness all occurs mainly with probably the first two feet. Then it's a little less and a little less by time you get out ten feet. It isn't worth, it's pretty much done. It's effective job. Don't put them next to each other. I recommend ten feet apart, but the code recommends, well, it requires they be at least six feet apart. This is another diagram. This is also is that in the background, measuring the resistance, a lot of people have the wrong idea about how doing this, They think they can take an meter on a cheap little meter and hook it up and measure the resistance. You can't do it that way. The number you get is useless. It takes a device to really be important. It takes a device that you connect onto your ground rod, and then there's a device here and it's got two other electrodes in. The farther these electrodes go, the more accurate the information is because most of that has to be within that ground right there. This is basically, once you get into the Earth, there's not much decrease in the voltage moving away from that ground rod. This device right here, I got a picture of one right there. These things are expensive. Most electricians, unless they do a lot of ground testing, they don't have these things. But it takes experience to be able to taught even how to do that. As we train people here, we make them do this right here on the, on the campus, so they'll know how these work. But these equip these devices, it takes a special device to be able to make it. Now here's the device, utilities. They just clamp it around the wire. It won't work for these kinds of installations where you drive a bunch of ground rods, hook it around the wire unless it's connected to the electrical system. Ground wires, by the way it's hooked up, it won't give you an accurate reading. It works really good on utility systems. But for individuals, case where you're just driving some ground rods and why don't know, is it a good job? If it's sandy soil, you better drive eight or ten of them. If it's pretty good, damp, moist, lo, clay, loam soil, two to three of them is probably going to do a good job. Same way with electric fencers. If you're using electric fencers to hold cattle, for example, the grounding is extremely important. Do never connect an electric fencer ground to anything that's part of the electrical system ground. You're asking for trouble. If you do that, that takes another lecture to get into that. But we have a little leaflet to tell you how to do it. Just let us know what MSU, ag engineering, and we'll send you these leaflets and so forth so you know what they look like. Okay, here's this shows a utility man using it. And this kind of a device that also costs these meters right here, cost about $2,000 a piece. Number one is they're expensive to buy, but they only work good on the electrical systems, like where they have lots of grounds on the utility system. When somebody says, we'll just use this, they don't work for normal electrical installations. Here's another way of doing it. Here's a case where usually you can't do this, but if you can measure a little bit of voltage off of the down ground wire and then you take a meter that'll measure the current that'll do it. But if you want to know how to do some of these things, just give me a give me a talk. Okay? And I think we're down just about to the end of the thing. Do you have any questions that you want to ask me? Sherman? The lightning suppressors that go on the bottom of the panels, are they sacrificial? One time and No. No good? No. They're they're used. It depends on May many years ago they might have not been, but if they're more recent devices, they're called surge suppressor devices, SPDs. And if it's put on your service panel, it needs to be a type one and they connect in. Electricians got to do this because if you're adding it, they've got to be head of the breaker And those wires are, you know, if sometimes when installation is putting in a brand new installation, the electrician may put it on the outside and tie it into the wires coming in. That's probably the best way he can. But yeah, they will they'll take repeated unless you just really got got a major thing that hits you. Okay. Most of the time they do. Well, I says I got away with I don't have one at my house. I'm waiting for the, actually, it's nice to have the power go out because then you know it's dead. Okay? So then you can open up and put in one of those SPDs. Sometimes people have asked a question about, about variable frequency drives. I don't see in most cases to where they could be used for, for applications for this. But if you need to know more about that, you can get ahold of of me at M issue it is just Serb at M issued a EDU. What's yours? L go at MSU DMU DU, just Serb. M. There's a lot of Serb been here now. But apparently I would set first one. Here's something that has happened from time to time. You're out there working with the system and you park your vehicle in the wrong spot. Maybe somebody comes along and let's go to dinner, or let's go to lunch, or I'll take you to the house and then you come back and you forgot that the system was running. This may be, it looks like kind of a joke, but on the other hand, this does happen to where that unit finally runs into something and causes damage. Maybe not like you see here. So anyway, be a little careful about that situation. So I don't know, does that answer your question? You can put them on, I just make sure if they're a newer one, it should say SPD. If you can't find them at one of the places like you got in Lowes, Home Depot, you can always go to a wholesale distributor for electrical stuff. Every major city has them and they'll probably have it, if they don't, they can get it within a day or two, okay? And they can get it, but it needs to be a type one SPD. And if you're going to put it on your house to specify, this is for a residential application, but the problem is getting them in, You got to have somebody who can deal with working around hot wires. And that's something that you got to have some experienced people who've actually done that unless the power is out and everything is dead, and then you could slip it in where it belongs. Any other questions that somebody has out there? Once again, if something comes up at the last minute and you think about it, just remember, you can send us an e mail. or and we'll be able to help you out. Okay? Thank you. Dr. Surbrook. Aluel. Dr. Go and Dr. Surbrook, thank you for your time. Well, thank you. We're happy to share what we've been able to collect over the years.