1 00:00:32,079 --> 00:00:36,119 What up? Everybody? Welcome to another episode and let's ask Paul the podcast 2 00:00:36,159 --> 00:00:39,880 where I, Paul Abernathy, do my best to answer all of your pressing 3 00:00:40,119 --> 00:00:46,960 electrical code related questions or anything related to electricity or the National Electrical Code, 4 00:00:47,119 --> 00:00:50,520 or the secrets of life and all that kind of good stuff. If you 5 00:00:50,560 --> 00:00:53,960 want to take part in it, all you gotta do is go to Paul 6 00:00:54,039 --> 00:00:59,000 Abernathy dot com. It's free, it's sponsored by Wicks, doesn't cost you 7 00:00:59,119 --> 00:01:02,840 anything, and it's a portal that was put up a couple of years ago 8 00:01:03,640 --> 00:01:07,879 to allow me to be able to address questions that people have. And it's 9 00:01:07,959 --> 00:01:14,359 kind of evolved because originally everybody knows my love hate relationship with social media. 10 00:01:14,400 --> 00:01:18,840 And when you have that love hate relationship with social media, you start to 11 00:01:18,920 --> 00:01:21,400 notice that you got to be there. You have to be there, it's 12 00:01:21,480 --> 00:01:26,280 just part of business. But then you look at all the comments and you 13 00:01:26,400 --> 00:01:30,719 realize that people just struggle. And the problem with social media is that everybody 14 00:01:30,760 --> 00:01:36,159 seems to think it's gospel and they listen to it, and people start propagating 15 00:01:36,280 --> 00:01:40,480 misinformation, falsehoods, and it's kind of like that thing you'll met, that 16 00:01:40,519 --> 00:01:45,560 little exercise where you get about ten people together and you whisper something in one 17 00:01:45,599 --> 00:01:48,519 of them's ear, and then they share with the next person, and the 18 00:01:48,560 --> 00:01:49,680 next person and the next, and by the time it gets to the end, 19 00:01:49,719 --> 00:01:55,519 the story is totally different. That reminds me of social media, okay, 20 00:01:56,159 --> 00:02:00,519 And the problem with it is some people believe something so passionately that even 21 00:02:00,560 --> 00:02:02,239 if they're wrong, they're going to argue it until they're blue in the face. 22 00:02:02,680 --> 00:02:07,959 And that's never a good thing for education. So while I believe that 23 00:02:07,159 --> 00:02:12,840 social media can be an important tool when it comes to education, it can 24 00:02:12,919 --> 00:02:20,000 also be detrimental to proper education, spreading valid information, that type of thing. 25 00:02:20,240 --> 00:02:23,639 So I had to take it in with the moderation and realize that it's, 26 00:02:23,759 --> 00:02:28,719 you know, consider the source. You know, consider the source when 27 00:02:28,719 --> 00:02:32,080 you're when you're doing this social media shopping when it comes to knowledge. Okay. 28 00:02:32,960 --> 00:02:37,360 Okay, So, as you've probably guessed by the title of this episode, 29 00:02:38,080 --> 00:02:42,000 on this Let's ask Paul, somebody asked me to talk about finding amp 30 00:02:42,039 --> 00:02:46,280 fridge ratings and the different ways that we can find amps for something and how 31 00:02:46,319 --> 00:02:50,960 we might do this. Okay, So I figured I would kind of do 32 00:02:51,080 --> 00:02:57,039 that and kind of break things down the best I can to help people understand. 33 00:02:57,080 --> 00:03:00,919 How would I, you know, calculate some of the things to find 34 00:03:00,039 --> 00:03:05,479 ampriage ratings depending on the question or what's presented. Okay, so that's what 35 00:03:05,520 --> 00:03:09,439 you're in store for today on this episode. And so I'm going to be 36 00:03:09,479 --> 00:03:16,240 spitting out some formulas. Okay, that's right. We're going to be spinning 37 00:03:16,240 --> 00:03:20,159 out some formulas that you can pause and jot down if you want, or 38 00:03:20,159 --> 00:03:24,520 you can just listen to them and that type of thing. And so we 39 00:03:24,560 --> 00:03:30,759 will be coming out with a pocket card that has all of this information on 40 00:03:30,800 --> 00:03:34,840 it, and we currently have one available for voltage drop, so make sure 41 00:03:34,840 --> 00:03:38,240 you go check that out over on our website fasttracksystem dot com. That's f 42 00:03:38,360 --> 00:03:42,759 A S T t R A X S Y S T E M, so 43 00:03:42,879 --> 00:03:49,560 exactly how it sounds fast tracks with t r X system dot com. And 44 00:03:49,639 --> 00:03:52,120 if you go there, you go to our store, you'll see that we 45 00:03:52,199 --> 00:03:54,439 have the voltage drop cards. They're pretty neat and even on the other side, 46 00:03:54,479 --> 00:03:58,680 I show you how they actually come up with the K value that you 47 00:03:58,800 --> 00:04:00,759 use in your equation, so I kind of show you how to do that, 48 00:04:01,800 --> 00:04:04,120 but I also give you the formulas and things like that. So it's 49 00:04:04,120 --> 00:04:08,439 a nifty little card to have in your wallet because you know, voltage drop. 50 00:04:08,560 --> 00:04:13,039 Even though it's not a mandated requirement by the ANC except for sensitive electronic 51 00:04:13,039 --> 00:04:16,120 equipment or fire pumps, it's talked about a lot and it can have a 52 00:04:16,160 --> 00:04:21,360 negative impact on the efficiency of your circuit and the things that are plugged into 53 00:04:21,360 --> 00:04:26,000 that circuit. So it is definitely something to be taken into consideration, and 54 00:04:26,040 --> 00:04:30,040 most engineers do. Most people I know do, even if it's not a 55 00:04:30,319 --> 00:04:35,399 mandatory requirement by the ANYCA for again, anything other than sensitive electronic equipment or 56 00:04:35,519 --> 00:04:40,800 fire pumps. Okay, so other than that, it's purely optional. But 57 00:04:40,959 --> 00:04:44,879 again it is something that people tend to take into consideration, and it can 58 00:04:45,040 --> 00:04:49,079 affect the efficiency of whatever the load is because certain equipment like to run between 59 00:04:49,120 --> 00:04:51,839 a certain voltage range, and if your voltage drops out of that, then 60 00:04:51,879 --> 00:04:58,319 it's going to be any fission prematurely cause the product to possibly fail. So 61 00:04:58,439 --> 00:05:01,199 things like that have to be taken into consideration. All right, let's talk 62 00:05:01,240 --> 00:05:05,920 about single phase. When we're talking about finding the amperage values on a single 63 00:05:05,959 --> 00:05:11,480 phase given a couple things. So if I happen to know what the watts 64 00:05:11,560 --> 00:05:15,920 are, the volts are, and I happen to know what the power factor 65 00:05:15,040 --> 00:05:19,439 is for a specific single phase load, and I'll give you an example. 66 00:05:19,920 --> 00:05:24,600 And in an exam type of question, they're probably going to give you all 67 00:05:24,639 --> 00:05:27,199 of these values, and if you don't know what the power factor is, 68 00:05:27,240 --> 00:05:30,000 then you go to unity. You can do one point zero zero if you 69 00:05:30,000 --> 00:05:32,639 want. But if they give you a power factor, then obviously when we're 70 00:05:32,759 --> 00:05:35,959 dealing with amperags, we want to take that power factor into consideration. If 71 00:05:35,959 --> 00:05:40,160 they're giving you that type of question, that has power factor in it, 72 00:05:40,800 --> 00:05:45,120 right, So let's look at the first one. So if we know what 73 00:05:45,199 --> 00:05:49,480 the watts are of the load, the formula is P over E times PF, 74 00:05:50,000 --> 00:05:55,759 PF being power factor, E being voltage and peving the wattage power. 75 00:05:56,800 --> 00:05:59,439 So if I gave you a question and it was one hundred and fifty watt 76 00:05:59,519 --> 00:06:02,199 load, and I told you that there was a power factor of eighty six 77 00:06:02,279 --> 00:06:06,120 percent or point eight six, if we work it into a decimal, go 78 00:06:06,199 --> 00:06:11,600 from the right side of the six move two spaces to the left point eighty 79 00:06:11,639 --> 00:06:15,759 six. Always try to put percentages into decimals when you're doing your math. 80 00:06:15,160 --> 00:06:18,800 It's a should be common knowledge by now, but just remember to do that. 81 00:06:19,759 --> 00:06:24,319 And then, of course we give you the actual voltage, which is 82 00:06:24,319 --> 00:06:28,639 two thirty volts. Again, folks, just to remind you, use the 83 00:06:28,759 --> 00:06:31,720 values they give you in the equation. If you're doing an exam, if 84 00:06:31,720 --> 00:06:34,000 they tell you it's two thirty volts, and you're in your mind thinking, 85 00:06:34,040 --> 00:06:36,279 well, wait a minute, this is a two forty volt circuit. No 86 00:06:36,639 --> 00:06:42,360 use what they give you, okay, Use what they give you, okay. 87 00:06:42,439 --> 00:06:46,120 So in this case, it would be one hundred fifteen hundred watts divided 88 00:06:46,160 --> 00:06:50,040 by e, which is the voltage times the power factor. So the first 89 00:06:50,079 --> 00:06:55,000 thing you want to do is always work the multiplication out first the lower part, 90 00:06:55,480 --> 00:06:59,399 So two thirty times point eight six. So I'm going to work it 91 00:06:59,439 --> 00:07:03,480 with you. So two thirty times zero point eighty six, and that gives 92 00:07:03,560 --> 00:07:11,639 us one ninety seven point eight. So now it's fifteen hundred divided by one 93 00:07:11,800 --> 00:07:16,279 ninety seven point eight. So fifteen hundred divided by one ninety seven point eight, 94 00:07:17,199 --> 00:07:21,120 that's going to give me seven point five eight. Three. Drop the 95 00:07:21,160 --> 00:07:26,560 three, so it's seven point five eight is the amps? Okay? That 96 00:07:26,720 --> 00:07:30,680 is the actual amps that is the current that we have for this equation, 97 00:07:30,920 --> 00:07:34,240 okay, and that took power factor into the equation. Now, interesting is 98 00:07:34,279 --> 00:07:39,800 if power factor wasn't in the value, then it would be fifteen hundred divided 99 00:07:39,800 --> 00:07:46,240 by two thirty and that would be six point five two. Okay, So 100 00:07:46,360 --> 00:07:49,800 it's uh, you know, the power factor is making it not as efficient. 101 00:07:50,519 --> 00:07:54,480 So the current went up, but if you take that out, that 102 00:07:54,519 --> 00:07:58,240 can be a different that's a difference of about one amp, believe it or 103 00:07:58,240 --> 00:08:03,000 not due to that power factor. Okay, So you want to make sure 104 00:08:03,040 --> 00:08:05,920 you're using whatever they give you. Definitely want to use what they give you, 105 00:08:07,839 --> 00:08:11,800 all right, So let's see here. So that would be an example 106 00:08:11,920 --> 00:08:16,680 when we know the WHTT is the voltage and the power and a power factor 107 00:08:16,720 --> 00:08:20,079 if it's available for the question. So the next thing you might get a 108 00:08:20,120 --> 00:08:24,759 question it says, what if I want to know what the answer are and 109 00:08:24,800 --> 00:08:30,120 I've got a load with a motor it's a horse power, but I don't 110 00:08:30,120 --> 00:08:33,480 know how to figure it out. Then they give you a power factor, 111 00:08:33,559 --> 00:08:39,720 they give you an efficiency and you're like, okay, well it tells me 112 00:08:39,759 --> 00:08:41,879 that it's an efficiency rating of ninety two percent, and it tells me, 113 00:08:41,919 --> 00:08:46,360 it's a power factor of eighty okay, and you may get this from the 114 00:08:46,440 --> 00:08:50,080 name plate of a motor. It's single phase and it tells me it's one 115 00:08:50,120 --> 00:08:54,159 hundred and fifty volt motor, and it's telling me that it is a half 116 00:08:54,559 --> 00:09:00,960 horse power half horse power. Okay. So immediately what some people would do 117 00:09:01,159 --> 00:09:05,519 is they would run to the back of the of motors and go to the 118 00:09:05,639 --> 00:09:07,799 FLC. But that's not what you do here, Okay, that is not 119 00:09:07,960 --> 00:09:13,159 what you do in this scenario. The equation is, now you do do 120 00:09:13,240 --> 00:09:18,039 that when you're sizing for motors for short circuit ground fall protection, when you're 121 00:09:18,080 --> 00:09:22,440 sizing for the conductors. All we're doing here is finding the amps based on 122 00:09:22,519 --> 00:09:28,440 a question where it asks you specifically to find the amps based on working this 123 00:09:28,559 --> 00:09:31,559 out. Okay. Now, interesting enough, this is probably going to be 124 00:09:31,720 --> 00:09:37,519 further in lined with what's on the name plate versus what's within the FLC because 125 00:09:37,559 --> 00:09:41,919 the name plates typically take things like efficiency and power factor into the equation. 126 00:09:41,519 --> 00:09:45,399 So this is going to probably harmonize more with what you would see on a 127 00:09:45,480 --> 00:09:48,240 name plate rather what you would see in an FLC, which is in four 128 00:09:48,360 --> 00:09:54,279 thirty nine two fifty. Just remember the FLC is what you're going to use 129 00:09:54,320 --> 00:09:58,120 in the code when you're sizing brand circuits, feeders from motors and motors, 130 00:09:58,120 --> 00:10:01,759 short circuit ground protection, things like that. And when you're doing the overload, 131 00:10:01,759 --> 00:10:05,679 you're going to use a nameplate. So all I'm showing you is if 132 00:10:05,679 --> 00:10:09,519 they ask you a simple question and want to know, what is the AMP 133 00:10:09,559 --> 00:10:15,399 load for a single phase half horsepower one hundred and fifteen volt motor that has 134 00:10:15,440 --> 00:10:20,240 an efficiency rating of ninety two percent and a power factor of eighty, how 135 00:10:20,240 --> 00:10:24,679 do you work it? Well? This formula which I encourage you to jot 136 00:10:24,720 --> 00:10:28,600 this down in your codebook if you have the If you're not preparing for an 137 00:10:28,639 --> 00:10:31,480 exam, you can write any damn thing you want in your book. If 138 00:10:31,480 --> 00:10:35,519 you're preparing for an exam, be careful make sure that they allow you to 139 00:10:35,519 --> 00:10:37,840 write in your codebook. And how do you determine that? Then you've got 140 00:10:37,879 --> 00:10:41,279 to go to the test center. Maybe they have a bulletin that you can 141 00:10:41,320 --> 00:10:45,039 look at, like PSI, if that's who's doing your testing. They will 142 00:10:45,080 --> 00:10:48,679 have what's called a guide in a bulletin, and it'll tell you what you 143 00:10:48,720 --> 00:10:52,120 can and what you can't do. That type of thing, So just be 144 00:10:52,159 --> 00:10:56,720 aware of that. And in your codebook if you can write in your codebook, 145 00:10:56,720 --> 00:11:00,399 like for example Texas, you can jot things in your code book if 146 00:11:00,440 --> 00:11:03,159 you want. The best place to do this is up near the front where 147 00:11:03,200 --> 00:11:07,960 the code panel members are because there's usually a lot of blank spaces up there 148 00:11:07,039 --> 00:11:11,320 or a lot of room to write stuff, and so it makes it nice 149 00:11:11,320 --> 00:11:13,399 to be able to jot your formulas, your owns low wheels, you know, 150 00:11:13,519 --> 00:11:18,240 example of a parallel series circuit, all those type of things, all 151 00:11:18,240 --> 00:11:22,080 the formulas. That's a great place to do it. But again, don't 152 00:11:22,120 --> 00:11:24,120 say Paul told you to do it. You get in trouble. You need 153 00:11:24,159 --> 00:11:26,360 to know whether or not you can mark in your codebook, and you're going 154 00:11:26,440 --> 00:11:31,159 to have to check with the bulletin or your test center wherever you're at in 155 00:11:31,200 --> 00:11:39,720 the country. So here's the formula. So the formula is horsepower times seven 156 00:11:39,879 --> 00:11:48,200 forty six. So that is the formula. Seven forty six is the actual 157 00:11:48,360 --> 00:11:56,480 wattage for one horse power. Okay, so it's horsepower times seven forty six 158 00:11:56,559 --> 00:12:01,840 divided by the vaults times the efficiency times the power factor. Well, remember 159 00:12:01,879 --> 00:12:05,399 what I said, you want to work the multiplications out first, So work 160 00:12:05,440 --> 00:12:11,279 the top out and work the bottom out. So let's worked the top. 161 00:12:11,639 --> 00:12:15,960 So we said it was a half horse power, right, so you take 162 00:12:16,000 --> 00:12:18,279 the one divided into two. That gives you point five. If you look 163 00:12:18,320 --> 00:12:20,919 at it and you know that half a horse power is point five, whereas 164 00:12:20,960 --> 00:12:24,879 one horse power is one point zero. Okay, you should know that, 165 00:12:24,039 --> 00:12:28,000 I hope, So point five is our horsepower. So we're going to do 166 00:12:28,200 --> 00:12:33,320 point five times seven forty six and that gives me three seventy three. So 167 00:12:33,360 --> 00:12:39,039 that's the top part of this equation. Now the bottom part was the voltage 168 00:12:39,080 --> 00:12:43,200 times of power factor. And remember we want to convert everything into decimal So 169 00:12:43,200 --> 00:12:48,279 we started the right side of the percentage and move two decimal spaces to the 170 00:12:48,399 --> 00:12:54,519 left, so that means that ninety two percent ends up being point ninety two, 171 00:12:54,600 --> 00:12:56,840 and then the eighty percent same thing. Start from the right, move 172 00:12:56,879 --> 00:13:01,600 two spaces to the left. Now that is point eight zero. Now let's 173 00:13:01,679 --> 00:13:07,320 do the multiplication. So one hundred and fifteen times point ninety two times point 174 00:13:07,320 --> 00:13:13,600 eight zero, and that is eighty four point sixty four. So now all 175 00:13:13,639 --> 00:13:18,879 you do is divide the top three seventy three into the bottom eighty four point 176 00:13:18,919 --> 00:13:24,000 sixty four and I'm going to do that now eighty four point sixty four, 177 00:13:24,519 --> 00:13:28,480 and that gives me four point four amps. So that is my answer when 178 00:13:28,879 --> 00:13:33,879 the horse power is unknown, but we do know what the horse power is, 179 00:13:35,759 --> 00:13:39,039 okay. Okay, So that was that was easy, right, So 180 00:13:39,120 --> 00:13:43,000 that's when the horse power is actually known, means you know what the horse 181 00:13:43,000 --> 00:13:45,879 power is. I don't know if I said you don't know it, but 182 00:13:45,919 --> 00:13:48,320 you actually know what the horse power is. Okay. So the next one 183 00:13:48,440 --> 00:13:52,600 is, okay, well, what happens if how do I find the amps? 184 00:13:52,759 --> 00:13:58,919 If I the kilowatts are actually known, so I happen to know what 185 00:13:58,960 --> 00:14:05,200 the question gives me kilowatts? Okay, same concept here there's no motor, 186 00:14:05,279 --> 00:14:09,080 so we don't worry about the efficiency. So here it's saying, okay, 187 00:14:09,159 --> 00:14:11,519 let's look at this question. It says I have a two hundred and thirty 188 00:14:11,600 --> 00:14:18,519 volt single phase circuit which has a twelve kW power load, whatever that may 189 00:14:18,559 --> 00:14:26,440 be, and it operates at eighty four percent power factor. Determine the current? 190 00:14:26,200 --> 00:14:28,960 Okay. So that's kind of a question that you may get on an 191 00:14:30,000 --> 00:14:33,639 exam. So how do I determine what the current is based on the fact 192 00:14:33,679 --> 00:14:37,320 that I'm giving the voltage, I'm giving the kilowatts, and I've given the 193 00:14:37,320 --> 00:14:41,360 power factor. Well, this formula is very similar to what we did with 194 00:14:41,440 --> 00:14:45,600 the previous one when we knew what the horsepower was. This is a little 195 00:14:45,639 --> 00:14:48,159 different though, since there's no horsepower involved. We don't equate the seven forty 196 00:14:48,159 --> 00:14:52,240 six. That has no play here. So now it's just killowatts times a 197 00:14:52,320 --> 00:15:01,360 thousand divided by volts times the power factor. Okay, so we know that 198 00:15:01,440 --> 00:15:07,559 it is twelve kilowatts, so we could skip one here and just go we 199 00:15:07,639 --> 00:15:09,799 know that twelve kilowatts the k is Kei low, so we know that it's 200 00:15:09,840 --> 00:15:13,919 twelve thousand watts. Okay, you could skip that one, but if you 201 00:15:13,960 --> 00:15:16,639 didn't, you just go twelve times one thousand, So that's twelve. And 202 00:15:16,679 --> 00:15:22,080 then on the bottom part it's the voltage times of power factor. Well, 203 00:15:22,120 --> 00:15:24,279 we said it was eighty four percent power factors. Start from the right of 204 00:15:24,320 --> 00:15:28,000 the four, move two spaces to the left. Point eight fours now are 205 00:15:28,159 --> 00:15:33,039 our multiplier, So we do two thirty. Remember, use the voltage they 206 00:15:33,080 --> 00:15:37,480 give you times point eight four, and that is one hundred and ninety three 207 00:15:37,519 --> 00:15:41,559 point two. Now that we have it figured out. We do the twelve 208 00:15:41,639 --> 00:15:46,559 thousand divided by the one ninety three point two, So it's twelve thousand divided 209 00:15:46,559 --> 00:15:50,919 by the one ninety three point two, and that's going to give me sixty 210 00:15:50,960 --> 00:15:54,440 two point one one. Remember that we can drop anything that is what under 211 00:15:54,559 --> 00:15:58,840 point five, So this is point one one, so we drop it. 212 00:15:58,919 --> 00:16:03,279 So the amps is six sixty two amps. So that's what our amp is 213 00:16:03,320 --> 00:16:08,320 for that twelve kW power load right at two thirty volts with an eighty four 214 00:16:08,360 --> 00:16:14,279 percent power factor. Okay. Now, again, these are just questions you 215 00:16:14,360 --> 00:16:17,159 may get on an exam and you're sitting there going, okay, I don't 216 00:16:17,200 --> 00:16:18,399 know how to work the power factor. I don't know how to work the 217 00:16:18,440 --> 00:16:23,440 efficiency. And that's that's why we're doing this. This that's what this episode, 218 00:16:23,440 --> 00:16:26,759 this podcast is all about, because I do get a fair enough questions 219 00:16:27,559 --> 00:16:33,919 that people ask about that. Okay, all right, Well, so this 220 00:16:34,080 --> 00:16:37,919 next one is one that says, Okay, let's assume we give you a 221 00:16:38,000 --> 00:16:42,600 question and we actually know what the kVA is or the kill of volt ampiers. 222 00:16:42,960 --> 00:16:48,159 Okay, so in this question, it's one hundred and fifteen volt circuit. 223 00:16:48,279 --> 00:16:53,200 It's a two kVA or y'all know k mean two thousand va. Vault 224 00:16:53,240 --> 00:17:02,639 ampires single phase generator operating at full load will deliver how many amps? Okay, 225 00:17:02,919 --> 00:17:06,480 how do you determine this one? Well, in this formula it is 226 00:17:06,640 --> 00:17:11,880 k it's the kVA or the killer vault Dampier's times a thousand, So that 227 00:17:11,920 --> 00:17:15,000 would you know, you'd be two times a thousand because it's two kVA, 228 00:17:15,279 --> 00:17:19,160 or as you as we said before, if you know already that two k 229 00:17:19,680 --> 00:17:23,839 va equates to two thousand va, then you can skip that little math, 230 00:17:25,319 --> 00:17:29,880 and so the top part would be two thousand and again, the bottom part 231 00:17:30,279 --> 00:17:33,039 is the voltage, which is one fifteen. So this is going to be 232 00:17:33,920 --> 00:17:38,279 two times one thousand divided by one fifteen, or in our case, two 233 00:17:38,319 --> 00:17:45,480 thousand divided by one fifteen, and that equals seventeen point four amps. So 234 00:17:45,559 --> 00:17:48,960 you just take two thousand, you can divide that by one fifteen, and 235 00:17:48,000 --> 00:17:52,799 you'll get seventeen point three nine one three. Obviously in this case three nine, 236 00:17:53,160 --> 00:17:57,319 you can work it up to seventeen point four and you're rounding it up. 237 00:17:57,759 --> 00:18:03,000 Okay, that's so that is okay, all right, So and we're 238 00:18:03,000 --> 00:18:06,319 working this. When we work this to the all the way down to the 239 00:18:06,359 --> 00:18:11,880 simplest form. Okay. Now, remember ampier is the rate of flow of 240 00:18:12,000 --> 00:18:15,599 currents. So this is again full load. We told you that it was 241 00:18:15,640 --> 00:18:19,599 a full load being delivered, and that full load on that one hundred and 242 00:18:19,599 --> 00:18:25,240 fifty volt two kVA. We didn't work anything, We didn't drop. It 243 00:18:25,400 --> 00:18:29,119 is full load, full being drawn. That full two kVA is being drawn. 244 00:18:29,440 --> 00:18:34,359 That would be again seventeen point four amps. Okay. So now up 245 00:18:34,359 --> 00:18:38,440 to this point, all of these that we've done have been pretty straightforward. 246 00:18:38,799 --> 00:18:44,160 But if you remember something, every one of these is dealing with single phase. 247 00:18:45,200 --> 00:18:49,519 So what do we do differently if we're dealing with three phase? Well, 248 00:18:49,559 --> 00:18:56,000 the only difference, folks, is that you're going to be throwing in 249 00:18:56,039 --> 00:18:59,319 the value of one point seventy three to two, which is a square root 250 00:18:59,359 --> 00:19:03,319 of three, okay, when we're doing three phase, because there's three legs 251 00:19:03,480 --> 00:19:07,279 square root of three. Okay. So if we know the watts the voltage 252 00:19:07,279 --> 00:19:14,200 in the power factor are known, then that equation is I equals p which 253 00:19:14,240 --> 00:19:18,640 is the watts divided by E times PF, which is power factor times one 254 00:19:18,680 --> 00:19:25,400 point seventy three. Okay. So in this case, the only differing variable. 255 00:19:25,400 --> 00:19:29,119 It's still a fifteen hundred watt load. The power factor is still eighty 256 00:19:29,160 --> 00:19:30,920 six percent. Y'all know how to convert that to point eighty six. Right, 257 00:19:32,039 --> 00:19:33,720 start at the right of the six two decimal spots to the left. 258 00:19:34,200 --> 00:19:38,680 You get it, and it's a three phase load with two hundred and thirty 259 00:19:38,880 --> 00:19:44,359 vault source. Okay. So in this one is fairly simple the same way 260 00:19:44,400 --> 00:19:48,480 we did before. The p here is fifteen hundred watts, the e is 261 00:19:48,519 --> 00:19:52,079 two thirty, the power factor is point eighty six. Remember eighty six percent 262 00:19:52,119 --> 00:19:56,759 converted to decimal and then times one point seventy three, which is the square 263 00:19:56,799 --> 00:20:00,160 root of three, because it is a three phase. So in this case, 264 00:20:00,200 --> 00:20:07,200 it would be fifteen hundred divided by two thirty times point eight six times 265 00:20:07,359 --> 00:20:12,000 one point seventy three two. That is three hundred and forty two. Okay, 266 00:20:12,359 --> 00:20:15,240 And hold, let me go in and let me work this all the 267 00:20:15,279 --> 00:20:21,319 way out. Two thirty times point eighty six times one point seven three two 268 00:20:22,799 --> 00:20:27,160 is going to be three forty two point five, okay, And so we'll 269 00:20:27,200 --> 00:20:30,519 just say at three foot two five. Now, one of the things we 270 00:20:30,559 --> 00:20:36,000 do at that point is take the fifteen hundred and divided by three forty two 271 00:20:36,000 --> 00:20:40,680 point five, and that's going to give me four point three seven, which 272 00:20:40,720 --> 00:20:42,720 I can round to full point four, and that's going to give me four 273 00:20:42,759 --> 00:20:49,720 point four amps. Okay, Now what if same thing? Now what if 274 00:20:49,759 --> 00:20:55,480 we have the same equation and they give you the horse power and they want 275 00:20:55,480 --> 00:20:57,319 to know what the AMPS is on this three phase Again, it's just like 276 00:20:57,400 --> 00:21:00,559 what we did in single phase. The only difference is we're adding that one 277 00:21:00,599 --> 00:21:06,680 point seventy three to two to the lower portion, or the denominator portion of 278 00:21:06,720 --> 00:21:11,000 the equation. Okay, remember when I say that though, folks to people 279 00:21:11,119 --> 00:21:17,319 not to get confused when I talk denominators and numerators and stuff like that, 280 00:21:17,319 --> 00:21:22,640 that you know the difference that the denominator is the bottom part, the numerator 281 00:21:22,720 --> 00:21:26,319 is the top part. So we're talking the denominator here is the bottom part. 282 00:21:26,519 --> 00:21:29,200 Okay. So how do we do this one? So same scenario. 283 00:21:30,119 --> 00:21:32,440 We have to know what the horsepower is. So let's read the question. 284 00:21:33,160 --> 00:21:40,240 Determine the AMP load of this three phase half horse power two thirty volt motor. 285 00:21:40,880 --> 00:21:44,680 The motor has an efficiency rating of ninety two percent, and this is 286 00:21:44,799 --> 00:21:47,000 very much going to be in line with the nameplate, by the way, 287 00:21:47,440 --> 00:21:51,079 and the power factor of eighty percent. Okay, Well, the first thing 288 00:21:51,119 --> 00:21:56,039 I like to do is convert all of these percentages into decimals, so that 289 00:21:56,160 --> 00:22:00,519 ninety two percent becomes a point nine to two, that eighty percent a point 290 00:22:00,519 --> 00:22:04,200 eight zero, right. And so now since we have the same half horse 291 00:22:04,200 --> 00:22:07,160 power, I'm gonna vide the one into the two. That's how I get 292 00:22:07,160 --> 00:22:10,400 the point five. Although you probably know a half of one horse power is 293 00:22:10,440 --> 00:22:14,400 point five, I'm just kind of talking through it for you. So I'm 294 00:22:14,400 --> 00:22:19,400 gonna haveo point five times seven forty six, and so the top part is 295 00:22:19,440 --> 00:22:23,400 gonna be three seventy three. Okay, that's the numerator portion, and then 296 00:22:23,440 --> 00:22:29,119 the bottom part I've got to do the math. So two thirty times point 297 00:22:29,200 --> 00:22:36,759 ninety two times point eight zero times one point seventy three two is two point 298 00:22:37,160 --> 00:22:41,039 two nine three point one. So I can just take the two nine three 299 00:22:41,119 --> 00:22:44,839 and drop the other. So now I just take the three seventy three, 300 00:22:45,480 --> 00:22:49,000 divide that into the two ninety three, and that gives me one point two 301 00:22:49,000 --> 00:22:55,920 seven ampires. Okay, so that motor and that's probably gonna be more in 302 00:22:56,000 --> 00:23:00,519 line with a name plate Okay, not the same as the FLC, which 303 00:23:00,519 --> 00:23:03,480 we're going to use for sizing circuits and a short circuit ground for protection, 304 00:23:03,559 --> 00:23:07,440 because the code tells us too. Right. This is kind of if you 305 00:23:07,480 --> 00:23:11,599 happen to get a question that's asking you to calculate this out, this is 306 00:23:11,599 --> 00:23:17,480 how you would do it. Okay, makes sense. Okay, let's keep 307 00:23:17,519 --> 00:23:19,359 going and kind of finish these out. So what if I have a three 308 00:23:19,400 --> 00:23:23,920 phase and I actually know what the kilowats are? So the only thing that 309 00:23:23,920 --> 00:23:27,519 you're changing with versus what you did with the single phase is that one point 310 00:23:27,559 --> 00:23:32,160 seventy three to two. So if I know what the kilowats are, what's 311 00:23:32,200 --> 00:23:36,240 the question? Okay, it's two hundred and thirty VOO three phase circuit now 312 00:23:36,640 --> 00:23:41,440 with a twelve kW power load that operates at eighty four percent power factor, 313 00:23:41,000 --> 00:23:45,920 determine the current Okay, simple question. I'm going to say, Okay, 314 00:23:45,960 --> 00:23:48,440 well, I can skip one step of doing the kW times one thousand, 315 00:23:48,440 --> 00:23:52,680 because I think we all know that twelve kW is twelve thousand watts, so 316 00:23:52,720 --> 00:23:55,920 I can skip that math. So that's going to be the numerator. That's 317 00:23:55,960 --> 00:24:00,599 the top part. The bottom part is the E time PF times one point 318 00:24:00,599 --> 00:24:04,359 seven three two, So we know that it is two thirty and I'm gonna 319 00:24:04,359 --> 00:24:08,599 work the math two thirty times, and we turned our eighty four percent into 320 00:24:08,680 --> 00:24:14,799 a decimal point eight four, so times point eight four times. And then 321 00:24:14,839 --> 00:24:18,359 of course the one seven three, which is a square root of three times 322 00:24:18,359 --> 00:24:22,400 one point seven four. Excuse me, one point seven three, So I 323 00:24:22,440 --> 00:24:25,039 don't know where I was getting that from. All right, times point eight 324 00:24:25,119 --> 00:24:30,119 four times one point seven three, which equals three hundred and thirty four point 325 00:24:30,200 --> 00:24:34,319 two three. Okay, So it's two three six, So we're gonna round 326 00:24:34,319 --> 00:24:38,759 this to three thirty four point two four, all right. So then you 327 00:24:38,880 --> 00:24:42,240 just take the twelve thousand, which is in the numerator's position, divided by 328 00:24:42,440 --> 00:24:48,559 three thirty four point two four, and that gives me a total of thirty 329 00:24:48,599 --> 00:24:52,240 five point nine zero. So we're gonna round this to thirty six ampiers. 330 00:24:52,400 --> 00:24:56,839 Okay, So the answer here is thirty six amps. Okay, so that's 331 00:24:56,880 --> 00:25:00,440 what the ampload is, uh for the cur draw is for this motor at 332 00:25:00,480 --> 00:25:06,640 this power factor. And then lastly, well, well we'll end this out 333 00:25:07,279 --> 00:25:11,319 on this episode with if you know the kill of old amp here, and 334 00:25:11,440 --> 00:25:15,759 you guessed it. It's essentially the same as we did before, except for 335 00:25:15,039 --> 00:25:18,279 the top part is the kill of volt ampier times a thousand. Well, 336 00:25:18,319 --> 00:25:22,440 I think we all know that if it's like a four kVA, then that's 337 00:25:22,440 --> 00:25:25,240 four thousand, so you can save a little step there. But if you 338 00:25:25,279 --> 00:25:27,200 didn't know, then you take the kill of old ampire, which if it 339 00:25:27,279 --> 00:25:30,200 was four kill of old ampiers, you do four times one thousand, four 340 00:25:30,240 --> 00:25:34,680 thousand. So what's the question? A two hundred and thirty volt four kVA 341 00:25:34,880 --> 00:25:41,279 three phase generator operating at full load would deliver blank amps. Okay, how 342 00:25:41,279 --> 00:25:45,599 do we prove it? Okay, Well, the equation is kill of old 343 00:25:45,599 --> 00:25:48,920 ampires times a thousand divided by e times one point seventy three to two. 344 00:25:49,519 --> 00:25:52,720 Well, we know the kkva was four, so four times a thousand, 345 00:25:52,799 --> 00:25:57,599 so the top numerator is four thousand, and then the bottom is going to 346 00:25:57,640 --> 00:26:04,240 be two thirty times one point seven three, and that is gonna give us 347 00:26:06,119 --> 00:26:08,839 three nine seven. Now, by the way, if you wanted to go 348 00:26:08,880 --> 00:26:12,279 all the way out at one point seven three two, you could, okay, 349 00:26:12,319 --> 00:26:17,640 but you're gonna get roughly the same values as using one point seven three. 350 00:26:18,039 --> 00:26:19,359 But if you want to work it all the way out. That's fine. 351 00:26:19,480 --> 00:26:22,519 If you want all of the square root of three, that's fine. 352 00:26:22,599 --> 00:26:26,680 I'll show you the difference if you want to see it. For somebody out 353 00:26:26,720 --> 00:26:29,359 there, I know this hollering saying, Paul, it's not one point seven 354 00:26:29,400 --> 00:26:33,039 three, it's one point seven three to two, okay, whatever, I'll 355 00:26:33,079 --> 00:26:38,039 do both for you. So in this case would be two thirty. We're 356 00:26:38,039 --> 00:26:44,480 doing the denominator portion two thirty times one point seven three, and that is 357 00:26:44,519 --> 00:26:48,279 three three ninety seven point nine. So I'm gonna take the four thousand. 358 00:26:48,640 --> 00:26:52,960 I'm going to divide that into three ninety seven point nine, and that gives 359 00:26:53,000 --> 00:26:57,640 me ten point zero five ams, so it's ten ams. But okay, 360 00:26:57,680 --> 00:27:00,920 Paul, Paul, you need to use the one point seven three two, 361 00:27:00,920 --> 00:27:04,640 okay, okay. So I'm gonna go two thirty times one point seven three 362 00:27:04,759 --> 00:27:10,000 two, and that gives me three ninety eight point three six. Okay, 363 00:27:10,119 --> 00:27:15,119 So three ninety eight point three six is my value. I would just use 364 00:27:15,160 --> 00:27:18,759 three ninety eight. Drop the point three six, so I would go four 365 00:27:18,839 --> 00:27:23,720 thousand divided by three ninety eight, and that gives me ten point zero five. 366 00:27:25,000 --> 00:27:26,759 Still drop the point zero five, so it's still ten amps, folks, 367 00:27:26,759 --> 00:27:30,319 it's not gonna make a difference. But if you want to use one 368 00:27:30,319 --> 00:27:33,400 point seventy three to two all the way out, go for it. Now. 369 00:27:33,440 --> 00:27:37,119 You can do that if you like. Don't make us complicated, please, 370 00:27:37,599 --> 00:27:41,200 it's not it's not worth making it complicated, all right. So that's 371 00:27:41,240 --> 00:27:45,759 how you find the amps, whether it's single phase, whether it's three phase, 372 00:27:47,359 --> 00:27:51,200 and you ask these kind of questions where they give you the kilowatts, 373 00:27:51,359 --> 00:27:55,000 or they give you the killer vault damp years, or they give you the 374 00:27:55,039 --> 00:27:59,000 watts the vaults and the power factor, or maybe when the horse power is 375 00:27:59,119 --> 00:28:03,079 known, they give you all these other variables. These are ways that you 376 00:28:03,119 --> 00:28:07,400 can answer these questions to find the ampage. Okay. So that's the whole 377 00:28:07,400 --> 00:28:11,519 purpose of this episode was called finding the amps based on the questions. And 378 00:28:11,680 --> 00:28:17,559 obviously normal OHMS law is pretty simple, right you have the E R Okay, 379 00:28:17,880 --> 00:28:21,480 so E the voltage divided by are the resistance will give you the current 380 00:28:22,000 --> 00:28:26,960 right, which is I. But here is just a little more complex when 381 00:28:26,000 --> 00:28:30,599 we're trying to find the amperage values based on whether it's watt's volts and kind 382 00:28:30,599 --> 00:28:37,000 of throw in the power factor scenario in or things like that because people ask 383 00:28:37,079 --> 00:28:41,359 about that. And also it was important to talk earlier about the horsepower for 384 00:28:41,440 --> 00:28:47,119 single phase versus three phase, just so you have kind of an understanding on 385 00:28:47,160 --> 00:28:49,119 how this all works. Okay, all right, folks, hopefully you got 386 00:28:49,160 --> 00:28:52,519 something out of this episode. Again, we're just talking amps, and that 387 00:28:52,680 --> 00:28:57,039 was it, And maybe we'll have another episode and I'll talk about maybe how 388 00:28:57,079 --> 00:29:00,680 to find horsepower, how to find wattage or whatever. If that's what you 389 00:29:00,759 --> 00:29:04,920 want, we more certainly can do that until next time, folks, Stay 390 00:29:06,000 --> 00:29:18,880 safe, God bless and we'll catch you on another episode