 Hey everyone, Chad here from the Electric Academy and this week we're going to start our discussions on the electrical code and Specifically this week. We're talking about conductor and passities. So let's get started Hey, everyone Chad here from the Electric Academy and welcome to our first in a series that I'm going to be doing on code I'm teaching an electrical course right now at BCIT and we're in right deep into code So I thought I'd build a couple of Code videos as I go along here something been meaning to do for a very long time and I just haven't gotten around to it And so we actually have a snow day here today in Vancouver. We we got hit with like a I don't I think I had like eight inches of snow I had to shovel off the driveway which I know for you people back east You're not gonna be feeling too sorry for us, but for us here in the West Coast man It's we're not used to that so just as a little disclaimer When I go over this today, we're gonna be talking about conductor and passity and I'm gonna be using the Canadian electrical code because I'm from Canada So all of you Americans are gonna be watching this There is a counterpart in the NEC and I'm not sure what it is, but it's the basic same idea So if you want to just watch along to see how we calculate conductor and passity The code rules be different But I think the ideas are the same and I know that our tables are very similar to the NEC tables So similar ideas as we go here. So let's get that digging in here I like to keep these things short and sweet as you know, so conductor and passity. How do we figure out what current? We're allowed to put on what conductors so the first off There's some factors that affect your opacity and factors that we have to consider There's the type of material that you're using and what I mean by that is are we using a copper conductor? Or are you gonna be planning on using an aluminum conductor? The next thing that we have to consider is the method of installation Is it gonna be enclosed and what I mean by that is it gonna be running some sort of raceway? Typically a conduit or maybe even the cable tray or is it gonna be run out in free air? So in my experience, so I haven't done a lot of free air and from what I can see and talking around and talking to people Freer seems to be a little bit rare freer. I thought would be like if it was inside MCC and kind of in the panduit there, but that's not for you That's still within an enclosed space. So again, that's something else Maybe if you have an idea maybe put that down in the comment section below here That'd be great if you can give me an example of what free air looks like or even add a picture or send me a Link there something I can look at but for the most part We're gonna be dealing with stuff that's enclosed because it's going to be in some sort of cable assembly or a conduit Next we have to do is we have to figure out what kind of insulation we're dealing with We have insulation around the wire for a reason it protects the actual conductor And it also prevents it from short-circuiting so we don't want the insulation burning off So we have to take into consideration the temperature rating of the insulation We also have to worry about the ambient temperature in the room So typically according to our code here, and that's what let me show you here this Canadian electrical code 2018 Typically anything below 30 degrees C we can go ahead and use our tables as we will but then anything over 30 degrees C We have to derate and we'll talk about that later on as we get going here So anything that's 30 degrees or higher or higher than 30 degrees is going to be have to be derated because again What happens here is we know that the conductors themselves when they have current running through it It creates heat and heat does stuff to the insulation So we have to worry about the current running through the conductors as well as the heat around the room If we have a room that's very hot Well, then we might have to derate the cable based on the opacity based on the temperature rating of that insulation Now as I mentioned We're going to be going a little bit through the Canadian electrical code If you can tell me put in the link in the description below story or the comments below Give me a comment on the NEC version like where do you guys down in the States? Find out where you you get your opacity of your wires in your cable. So again this little tutorial I'm going to be going through it's going to be based off the four or 2018 Electrical code, which is finally just adopted. I'll be addressing that in later videos But so we're going to be using specifically when we're talking about Empacity of wires and cable we're going to be using rule four dash zero zero four So the opacity for copper wire if you would turn with me if you've got your code book open You would go to four dash zero zero four and I'm just opening it up here just so Know that I'm actually looking at this stuff That's our rule there and for copper wire we have sub rule one I'm not going to read through sub rule one. I'm just going to hit on the major points here But that's where we're finding all our rules, but opacity for copper wires So it tells us in four zero zero one that if we're dealing with single conductor and free air We get our starting capacities from table one, which we'll go to in a second. I've got some examples So don't worry about that But if we're dealing with one two or three conductors in a raceway or cable assembly We're going to table two and this is only for copper. This is not for aluminum So table two is where we're going to be going and honestly I spend probably 95 of my time starting in table two when I'm talking to my students And when I was out in the field because I'm dealing with conductors that are going into a conduit Or into some sort of cable assembly like a tech cable Multiconductor tech that sort of thing. So that's the opacity for copper wire is in four dash zero zero four sub rule one Ampacity for the aluminum wire is same ideas It's found in four dash zero zero four sub rule two Because in that area, we're they're very similar rules because all we're dealing with is different material and aluminum Is got can handle a little bit different opacity. So we'll talk about that. So your tables are going to be different So instead of using tables one and two For a single conductor in free air, we're going to use table three So it's got its own for aluminum and then we've got table four For one two three conductors in a raceway or cable assembly for aluminum. So again The important part is realizing are you dealing with aluminum wire or are you dealing with copper wire because your tables are totally different Now we also have some correction factors Because we're going to have to de-rate at some points So that takes us to some other tables here now in these rules in four dash zero zero four sub rule one and sub rule Two they refer you to this table here and I think I've got that this down first Yes, I do table five C and it says correction factor for four or more conductors in a raceways for table two and four So tables two would be your copper conductors up to three and tables four is your aluminum conductors up to three But if you have more conductors then you're going to have to de-rate because if you have more conductors carrying current It's going to create more heat and that heat is going to create problems for the insulation So we need to de-rate it. We need to bring the heat back a little bit So that's table five C five a That rule and I I've mentioned this later on in the presentation, but that Table it's referred to in sub rule seven four dash zero zero four sub rule seven item b item i And it says the correction factor specified in this rule shall apply only to power and lighting circuit conductors as follow The opacity correction factors of table five a where conductors are installed in an ambient temperature exceeding Or anticipated to exceed 30 degrees celsius. So again, we're up in canada. We're using metric So you go ahead you americans and make go to uh, you would be dealing with fahrenheit Five b is correction factors for tables one and three where single conductors are in free air and in contact with each other So I don't go over those in the examples because I have rarely used that actually in real life And again, if you have used that in real life, please go ahead and leave a comment below I would love to hear it and see where we're using this thing because honestly I yeah, I teach this stuff, but there's things that I don't know yet too So that's what I love about having this channel Is that I learned just as much from you guys is that hopefully that you're learning from me So here we go. We're going to go over some examples of how this stuff works Example number one So what we're going to do is we're going to calculate for one number three r90 copper conductor in free air So the first step here is we're going to go to table one And our tables in the 2018 code book. Let me just Open it up here I find them on Starting to could do Starting on page 417 for the tables and that's in the 2018 code book But they're all around the same area if you're if you're using the 2015 I think the tables are very similar. I don't know if there's any impassive changes to the tables I should know that I should go over and do a video on the code rule changes From the 2015 to 2018, but that's another video for another time. So anyways, we're starting with table one And it's important here if we go to table one, you're going to see that you have down the sides here You've got and let me hold this up so you can see it You've got your Size your awg size your american wire gauge size. So you've got that going down that side But then along the top here, we have different temperature ratings So we have to take that into consideration in this one. We're using r90 So we're going to use the 90 degree column, which is this column here and then work our way down So that's important So our 90 degree column we go to number one and we should end up starting with If we're using table one For one number three conductor I've got 165 amps And that's it. I only wanted to know what one was so there you go table one done example number two Calculate for three number three tw copper conductors run and conduit So we know that this isn't single conductor run for year and it's copper So we're either using table one or two Not single conductor run for year. So then we're going to table two. So I turn the page to table two Then we need to go down and we need to figure out What our uh I'm past or not opacity. Sorry temperature rating of the wire is tw just as an fyi is rated at 60 degrees celsius so That columns again. I'm going to be using six. There's the columns across you've got 60 degrees 75 degrees 90 degrees 110 degrees 125 degrees and 200 degrees We're using the 60 degree column in table two So we do that and if we run our fingers down there number three We end up with 85 amps in the 60 degree column So far so basic, right? Let's keep going an example three. Let's kind of mix it up a little bit We're going to calculate the opacity for each of six number 12 r90 copper conductors run and conduit So again our baseline is always going to be table two from this point on because we're using more than We're assuming that they're it says conduit. So we know that we're using table two as opposed to table one So we start there into table two and we work out that Number 12 are 90. So number 12 90 degrees. We start out with 30 amps Then what we need to do is we need to go to table 5c because 4-004 sub rule 1 Tells us that if you have more than three conductors, you have to derate according to table 5c So we kick over to 5c And we see that we've got six so running across there four to six means that we have to derate at 80 percent or 0.8 So we're taking that 30 Actually got 35 amps that should say 30. Sorry Little mistake there should say 30 amps times point eight. I've got the right answer though is 24 amps, right? So that's what we've got at that. So again, what we do is we go to table two Get our our base point, which is 30 amps We go to table 5c and we find that we need to derate that by 80 or 0.8 So then we went 30 not 35 30 times point eight equals 24 amps All right, let's go to example number four Calculate the opacity for each of eight number 10 RW 75 copper conductors run in a conduit at an ambient temperature of 50 degrees c Couple minutes ago. I mentioned this ambient temperature. We are above 30 degrees c that's going to cause some issues We're going to have to derate for that So first thing again table two we go to table two and we figure out that number 10 is good for 35 amps Okay, so that's our starting point Then we notice that we've got eight of these wires. So it's more than three. So we have to go to table 5c From 5c we find that we have to take it at 70 percent We're going to figure out 35 amps times point seven equals 24.5 amps Now here's the kicker What we need to do now is we need to go to table 5a Because it tells us some 4004 sub rule 7 item i to go to table 5a And what we're going to do is find our impasse our ambient temperature is 50 degrees So we're going to run our finger down to 50 degrees and then we're going to go across and now we see that we've got 75 It's rw 75. We're going to be using the 75 degree column. So we're going to be multiplying that by 75 percent Or 0.75 So we're taking 24.5 amps and multiplying it by 0.75 To get 18.375 amps and that's the maximum opacity that we can put on each of these eight Because there's eight conductors. So we need to derate for the fact that there's more than three And then it's going through a very hot room a 50 degree c room Celsius. So again, we have to derate again because of the temperature And we got one final to go here We're going to talk about this one. This is a good one calculate the opacity for each of four number two r 90 Aluminum conductors. I'm trying to trick you up on this one when installed with two number eight tw aluminum in the same conduit So what I'm going to do here is I'm going to kick it back for a second over to four dash zero zero four And I want to read you that rule that talks about the fact where we've got more than we've got two different temperature ratings See we've got over here. We've got r 90, but then we have tw which is rated at 60 degrees So if you look here, our first step here is going to be to go to table four Why table four because of this the aluminum the aluminum conductor. We're not using table two anymore We have to use table four because I said aluminum watch for that So table four is where we're starting Then we go to table or sorry rule four dash zero zero four sub rule 14 And let me read to you from the good book here and it says The opacity of conductors of different temperature ratings installed in the same raceway Shall be determined on the basis of the conductor having the lowest temperature rating We look here. We've got a 90 degree rating. We've got a 60 degree rating What we're going to do is treat everything that's in the same conduit like it's 60 degrees Okay, because we're going to go with the weakest link So even though this installation here is rated for 90 degrees, we're going to treat it like it's 60 degrees So what we're going to do is calculate out our four number twos as they are twos or 60 degree wire So we do that and I'm going to go to table four And I'm figuring out four number two So I go to number two And I run my finger across and I skit 75 amps because I'm in the 60 degree C column because I'm treating everything in that conduit like it's tw or not 60 degree cable Then we go to table five C because I have Four wires plus two hours. I have six current carrying wires in the conduit. So I need to derate for that So I'm going to go four to six gives us a duration factor of 80 or 0.8 So there we go 75 amps times 0.8 gets us 60 amps And that gets us everything we need for this point. I don't have any other ambient temperature We can assume that it's going to be 30 degrees C And away we go One more thing when we're dealing with conductors in the conduit When we're dealing with bonding conductors or a true neutral the neutral that has actually meant to not carry current Or is there to you know, provide a reference point as well as carry the unbalanced current So not much current because you're not meant to be current carrying conductors. You don't count them so if this had say Four number two are nineties and two number eight tw's and a bonding conductor You would still consider it to be six wires. You don't count that bonding conductor or the neutral that's in there Okay, that's all I got for now Do me a favor if you're getting anything out of these videos, please leave a comment down below I'm trying to get way better at responding to them. And if you could just hit that subscribe button that Let you know when the next time I've got a video coming out I'm trying to release at least a video a week in the 2020 year And I'm trying to double down on my code because I really want to get some code videos out there Make sure you hit that bell notification as well. If you have any questions at all I'm leaving some links to some stuff down in the description below So you can get some more information about what's going on with the electric academy And I just want to say thanks for everybody who supported me along the way here And we're just going to keep on keeping on have a fantastic day and we'll see you later