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Thanks!

Glad you like the videos! My instinct is to answer yes to both questions, so perhaps I don't fully understand the distinction you're making. No matter where the largest motor is in on the service, you want to take 125% of it's value - unless it's the lesser of noncoincident loads; then you would only take 25% of it. That's my understanding of what they have written in 220.60. But this code section is problematic and needs to be revised. So until they fix it, we have to make an educated guess as to their exact intent. An alternative guess is that they want us to compare the noncoincident loads after taking the motor load at 125%, and then take the larger of the two. This, of course, assumes the motor load is the largest on the service. This is actually the way I personally think noncoincident loads should be treated. But if this is what they intended, their wording is incorrect because they don't even mention anything about the largest motor on the service in 220.60. If you haven't already, you can check out my video on Noncoincident Loads here: ruclips.net/video/_YVvb2YlqUc/видео.html Hope that helps answer your question!

That would make the most sense to me on how noncoincident loads should be handled. I wish that is what the text said. Unfortunately, that is not the meaning that the wording conveys. It would be simple to make that clear, yet they have overcomplicated it. I have submitted a formal petition to the NFPA to revise 220.60, but I'm not holding my breath. They had a chance to fix it after 2020, but arguably made it worse in 2023.

Since this is the Optional Method, almost everything is taken at nameplate value. Check out this video for a thorough explanation of the Optional Method. ruclips.net/video/pjSYPcfyKx0/видео.html

Due to its phrasing, it's a very tough section to get a clear meaning from. There are two main ways the second sentence of 220.60 can be taken: either as complementary, or as exceptional to the first sentence. The wording specifies that you take 125% if it is NOT the largest of the noncoincident loads. And note that it doesn't say to do so IN LIEU OF the first sentence. It is written as an additional statement, not as an exception to the first statement. So this 125% of the smaller load would be in addition to the largest noncoincident load. In this case, that would be 12,000VA + 8125VA = 20,125VA. A monstrously huge value. If this were the case, what is the point of discussing noncoincident loads if they are simply going to be added together? So, I don't believe that is their intent, but that is how they worded it. However, let's say for a moment that they meant the second sentence to be an exception to the first. Then in this example, we would take ONLY the heat pump load at 125% (8125VA) and eliminate the larger furnace load (12,000VA) from the calc. I certainly don't think that is what they intended either. We'd be leaving the largest (by far) load of the whole service out of the calculation altogether. Anyways, I hope I didn't just add more confusion to the mix! The code-making panel has some more work to do before the next NEC gets printed, IMO.

Any load that is not part of a particular unit's feeder is considered a "house load". This primarily applies to multifamily buildings where there is a panel that supplies loads for common areas (like parking lot lighting, corridor lighting, fire alarm equipment, etc.). The bill for these loads are usually split among the occupants and are on their own feeder and meter. Since they are not included in an individual unit's calculation, they must be tallied up separately and then added to the total. House loads are typically figured under the commercial calc, but check with your jurisdiction.

House loads are typically figured under the commercial calc and then added to the total. I haven't made a video for it yet for a few reasons: 1. There are so many varieties of house load arrangements, it would be nearly impossible to cover all of the types. Different jurisdictions may treat them differently since they are not explicitly covered in the NEC. 2. The commercial calc is very straight-forward and it is easy to plug the loads in as if it was a commercial building. 3. I'm in the middle of producing my 2023 series and am spending my time on those. I would like to do a house load video eventually but it is lower priority at the moment.

No, I haven't, simply because there is no universal way to treat them. House loads are generally done according to Part III of Article 220 (see 220.84(B)). Typically, you would just use the commercial calc table (ruclips.net/video/1tQAf7lw-Uw/видео.html) for your house loads, and then add them to your multifamily calc. But this may change from jurisdiction to jurisdiction. Some municipalities may treat house loads as commercial, and some as part of the multifamily. You will have to check to be sure in your area. In my area, we treated large house loads as commercial in most cases. Little quad-plexes and such that might have a tiny house panel for site lighting and common area lighting would just be included with the multifamily calc. Maybe other folks here can chime in with their experiences. If I were taking a test, I would go with the commercial route, since that's generally accepted as the codebook answer.

@@simply.electrical does including it with the multifamily calc mean just counting the 3x VA/sq. Ft then the appliances/ motors at nameplate with no additional things like SABCs/laundry

@@86aoshi I'm only talking about the very small multifamily buildings that have a tiny house panel with a few common area lights, etc. on it. In those cases, we just treat it like it's part of one of the units. It's such a negligible amount, it really doesn't affect the total to any significant degree. However, if it is a larger house load panel (with perhaps laundry facilities, workout room, pool, etc.), I would treat that panel as a commercial calc, and then add the result to the "House Loads" part of the table in this multifamily calc. Hope that helps!

I'm working to get them posted on a site. Hoping to have them up in a couple of weeks. Sorry for the wait!

I see you were able to make sense of the NEC example. I'm not a big fan of the examples in the Annexes, simply because I don't think they do a very good job of explaining themselves. It leaves you scratching your head more often than not, IMO. That said, they are helpful if you have no other resources to draw on. Thanks for the comments!

See comment below...

Thanks!

I'm working to get them posted on a site. Hoping to have them up in a couple of weeks. Too many irons in the fire. Sorry for the wait!

I'll post them on a site as soon as I can as static worksheets. They won't be Excel at first. That will take more time to produce. Sorry for the wait!

You are absolutely right. I must have fat-fingered the calculator. I apologize! No matter how many times I check my work when making these videos, there always seems to be something that gets overlooked. Thanks for bringing it to my attention. I'll make a note in the video at that point.

EV chargers would fall under appliances in 2020. However, in 2023, a new section was added - 220.57. This changes two things: 1) It requires a minimum rating of 7200VA (or nameplate, if higher). 2) Also, it no longer allows the 75% demand factor to apply (4 or more appliances) in 220.53.

It depends on your situation. I would generally recommend the optional method for most applications. It is quicker, easier, and doesn't require as much detailed data collection. However, the standard method is more precise. So, if you are using the optional method, and end up close to a service size limit (say, you calculate185 amps), then it would be good to run it through the standard method also. You don't want to cut it too close on a 200 amp service. ALWAYS leave plenty of wiggle room, if you can. Keep in mind, that there are rare occasions where a standard calc actually comes in lower than an optional calc. Usually only on tiny buildings.

How can I get both templates (optional & standar methods) for single dwelling and multiple dwellings units calculation spreadsheet to compare Thanks

@@jirehelectric I'm working on getting the tables available for download. I'm putting together a website in my spare time and unfortunately it's taking a little longer than I'd hoped. I'll send out a notification when they are ready. Sorry for the wait!

@@simply.electrical That would be great. I just got my electrical contractor license and I have been working on sizing a 6 dwellings units service plus house, the square footage differs from each other and your videos have helped a lot so you explain more clearly that others on you tube and because sometimes there is no time to go all the way to the process a template would help a lot. Thanks for your hard work. 👏 Sorry for my English I am second English speaker.

Hi Dustin, I really appreciate the offer. I'm no Excel wiz by any means, so that process is taking a bit longer than anticipated. So what I plan to do in the interim is make the tables available as printable forms - to copy and practice on. You would still have to do your own math, but at least all the criteria would be given. That's the best I can do at the moment. Hoping to have those available soon. Once I have it done, I'll post the link on every video. Thanks!

@@simply.electrical No Worries. Thanks for the reply

@@dustinfritz4544 You bet. I'll also send out a notification when I have them ready.

Glad you found it helpful. Unfortunately, I'm still working on making the tables available for download. I'll hopefully have that done soon!

Any extra motor loads would fall under 'Appliances'. Only the largest motor of the building gets the extra 25% added. So if one of your motors is larger than the heat pump, that is the load you would add 25% to - not the heat pump. See 220.53 for appliance criteria.

You're welcome!

Unfortunately, I'm still developing my website. At the moment, the best way to get the tables is to screenshot and print the black and white copy that I put at the end of each Deep Dive video. Eventually, I'll have the tables made into fillable spreadsheets. That way you can just input the data and it'll auto calculate. Sorry for the wait!

Thanks! Unfortunately, I'm still developing my website. At the moment, the best way to get the tables is to screenshot and print the black and white copy that I put at the end of each Deep Dive video. Eventually, I'll have the tables made into fillable spreadsheets. That way you can just input the data and it'll auto calculate. Sorry for the wait!

No, a service load calc simply establishes the minimum load of the building. It makes no difference what the power source is. It could be powered by a generator, solar panels, wind turbine, exercise bicycle/magneto combo, or the Tesseract - doesn't matter. However, whatever it is, pay attention to the voltage because that tells you how to find amps. The state exams will often times put in extra information that has no bearing on the problem - just to throw you off. They're trying to make sure you really know your stuff.

Nice catch! I apologize for that mistake. A 7kW range is unusually small, and I'm so used to using Column C (especially for a single-family calc) that I defaulted to it. You are totally correct, though. Column B should be used here in order to get the minimum load. I'm so grateful for everyone's comments pointing out these kinds of errors. You keep me on my toes! I've made a note on the video at that point, so going forward, folks will be warned. Thanks for bringing it to my attention, as it helps everyone here!

Thanks!

The formula for calculating amps for a 3-phase load is: Watts/(Volts x 1.732) = Amps Remember, you have to multiply the volts by the square root of 3 when calculating these 3-phase loads. Hope this helps!

Did they tell you that the A/C load was indeed the largest load of the building? Because on a test, you are not expected to assume. They will give you that kind of pertinent data. Some people add the extra 25% during a different step, so could they have perhaps done that? Hard to know without seeing the whole problem. Was this a test, or maybe a practice test, or worksheet?

@@simply.electrical it was the only motor in the calculation but taken at 100 and not 125 seems wrong No mention of heat or any other motors Practice Exam

@@ericpolk9004 One thing to note about practice tests: Many of them are imperfect. They can be written by well-intentioned folks who are trying to help, but they do have some mistakes sometimes. I'm not saying that is the case here, but it's a possibility. I'm not sure where your practice test came from. Can you reach out to them to see how they arrive at their answer? The state exams tend to be more vetted and accurate. Often times, on a state exam, the calc problems will be very abbreviated. They are not looking for a whole service load calc most of the time. So you won't treat it quite the same way. You just need to give them what they ask for.

Thanks, you bet!

Thank you!

Most of the 15kw furnace load is due to the heat strips. The blower motor is a small fraction of that. In fact, much of the time in the field, the blower motor is not even taken into consideration because it is such a minimal load as compared to the heat strips. Remember, when taking into account the largest motor, it cannot include other loads (e.g. heat strips) - even though they are both part of the same furnace unit when it's all assembled. The reason the AC or heat pump is treated differently is because the compressor motor is by far the largest load of the unit - the opposite of a furnace. I hope that helps clear it up a little!

Yes it does, thanks for the feedback💯💯💯

Yes, as long as you don't have any other larger motors elsewhere, of course. In most cases for residential, the AC or heat pump will be the largest motor load of the building - even with an electric furnace (because the heat strips are the lion's share of the load, not the motor).

I'm currently working on making the tables available for download. When I have them ready, I'll post a link on every video. Thanks!

Sorry, I don't have them available for download yet. The best you can do at this point is screen shot it and print it out. I'm working on a fillable calculator, but it will take a little time to complete. I appreciate your patience. :)

Please give us excel😢

@@kailashsoni3576 I'm working to get them posted on a site. Hoping to have them up in a couple of weeks but it's slow going. Sorry for the wait!

Sorry, I don't have them available for download yet. The best you can do at this point is screen shot it and print it out. I'm working on a fillable calculator, but it will take a little time to complete. I appreciate your patience. :)

I appreciate your offer. If you have specific questions, could you post them here, one at a time? That way other folks can take advantage of the discussion, too. Also, you can refer back to them for reference as needed.

Please elaborate on your question.

In most residences, the AC/HP compressor motor will be the largest in the occupancy. So that is the assumption in these calcs. On a test, they will tell you which is the largest motor if it's part of the calc.

Yep, I used the same template as the other calc and forgot to change the value in the problem description. My bad. I added a caption to the video at that point for now. I'll be making a new video soon. Thanks for pointing that out!

Thanks for making the video. It is helping me alot

@@raymondmolander8590 Glad you found it helpful!

Hey Eric, you are correct. The equation should be: 8kw + 8kw(14kw-12kw).05 = 8.8kw. Whoever wrote the problem made a mistake. By their logic, a 13kw range would have a larger demand than two 12kw ranges.

Thank you! Glad you found it helpful.

That's correct. The only occupancies that allow for an optional method calc are specified in Part IV of article 220. However, take note that 220.87 does pertain to existing loads, in case that is relevant to your situation.

@@simply.electrical Thank you for clarifying, Apricate that. you can made branch circuit design video for design engineers.

310.12(B) has specific criteria requirements (120/240-volt systems, 100-400 amps, etc.). However, this criteria will apply to most dwellings out there. If the criteria are met, the 83% would be applied after the calculation from 220 is completed. And keep in mind that 310.12 pertains to conductor sizing, not service sizing.

Yes, I do plan to expand on these videos in the near future. Unfortunately, I can only do so as time allows. At the moment, I'm not sure how soon it will be. Thanks for your interest!

@@simply.electrical Thank you

The service amps is 503. You would have to go to table 240.6(A) to find the standard breaker size. You can’t use the standard 500 amp breaker because your calculated load is over that. The next standard size is a 600 amp breaker. Go to table 310.16 and go to the 75 degree Celsius column. Find the wire size that has an ampacity of 600 amps or more. The service wire size will be 1500 kcmil Copper or parallel runs of 500 kcmil Aluminum.

That's correct. You'll notice that the note for Table 220.12 was added in the 2020 NEC, stating the inclusion of the 125%. And you can see that the values have all been adjusted accordingly. They did a whole re-vamping of the table in 2020.

Thanks i appreciate your channel I'm up too 15 masters now and you have helped tremendously @@simply.electrical

That's correct. You'll notice that the note for Table 220.12 was added in the 2020 NEC, stating the inclusion of the 125%. And you can see that the values have all been adjusted accordingly. They did a whole re-vamping of the table in 2020.

What NEC year is your test on? 2020 and 2023 include the 125% for general lighting in the T220.12 value already (see note at the bottom of the table). You should not have to add it in again. If your test is on the 2017 or older cycle, then yes, you would have to add it in.

it was 2017 but i passed it already it was for the CE Tennessee Masters @@simply.electrical

I'd be happy to make more examples. What are some occupancy types you'd like to see? With commercial, the possibilities are almost endless because of various combinations. If you give me some specific direction, I'll see what I can do. Thanks!