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Hi, this is George with Argo electrical services, and I am the surge protector guy. So this is our second podcast today, I want to welcome everyone. So the title today is, is your electrician performing load calculations. And so I had to shorten up my title. But anyway, the question is, is your electrician performing load calculations before adding circuits or panels to your electrical system. So one of the things that I’ve been doing to try and improve my marketing is, is YouTube videos, and I try to watch other people that are in my industry, it’s a beautiful thing, YouTube, we can get tons of information right off of our phone, or straight to our TV. But anyway, I was watching a video the other day, and this fella was reading a script. And he’s, he says, there’s your interior panel have enough spaces. And if so, then you can just add a sub panel. And I got to thinking, Oh, my Lord. So you know, in the world of electric vehicles, and I live in northeast Georgia, about 45 minutes outside of Atlanta. In the past 15 years, since I’ve had my own business, I’ve made quite a good living, of upgrading services and adding stuff to people’s homes that might not have been there, when the home was originally built. There are a lot of two story homes around here with unfinished basements, and the electricians at the time went in there and put either 150 amp service entrance, or a 200 amp service entrance. But the new homeowner or the existing homeowner, there’s a lot of flipping of houses going on around here. And, and but people want to finish the basement, and maybe they want to, you know, give their kids living space down there and make a mother in law suite, or whatever. But they want to add a little bar kitchen area in the home, they want to add potentially a HVAC unit, you know, which would provide heating and air plus, you know, all kinds of different circuits, maybe they want to put a shop, whatever. And of course, you know, in the last few years, we’ve done quite a few installations for Evie chargers. And these items, tax the electrical system. And if you have a home, that was 2500 square foot to begin with not counting the unfinished basement, right, and then you add another 900 to 1200 feet in unfinished basement, then you’re bouncing close to you know, 30 504,000 square feet, just depending on the size of the home. And, you know, I can’t tell you how many times I’ve done remodel projects in this area. And I’m not just talking about in one county I’m talking about in multiple counties, all of them all the way out of North Atlanta, right on up into, you know, into the mountains. And I go in there and I tell the the inspector that comes by to do the electrical inspection. It’s like, hey, well, you know, here, we, we ran this, we put 100 amp panel down here. So we can feed this new HVAC unit, these five circuits in the house, yada yada, whatever. And the God never asked me for a load calculation, we change out meter bases and panels in older homes all the time, the home might be 50 years old. And of course, I don’t want to knock the entire home down and start over. But you know, they need to upgrade their service. Because we just, we use more stuff today than we ever have. And none of these inspectors have ever asked me for a load calculation. You know, in commercial jobs, you have architects and engineers, and they have stamp prints that they put out. And those prints are approved before you ever start work before they ever even issue permits. In the residential world not so much. It’s kind of a bill to suit thing. And as long as it seems to make sense to your inspector and the contractor. You know, they go ahead and let you do it. And you know, and at the end of the day, I’m not sure how it is outside of the state of Georgia. But I know in North Georgia, when you get your approval for inspection at the end of the remodel or whatever. They’re going to send you a piece of paper that says even though you have had your property inspected by the authority having jurisdiction, whether it’s the county, the local county or the city that you live in All liability falls back on the contractor. And I’m sure the county’s real happy with that. But the next that leads me to my next question, what happens when a catastrophe happens in yourself improved property. First and foremost, you need to have it permitted. Otherwise, if there is a catastrophe, the insurance company will never pay, you know, and it’s to protect you against people who do unethical work. Or maybe they just made a mistake. Maybe they weren’t, you know, maybe they had a faulty piece of equipment and caught fire. But at the end of the day, you want to protect yourself as a homeowner, non permitted work is a risk for the property owner. All right. And furthermore, the National Electrical Code requires load calculations. Before adding circuits branch circuits to the system or sub panels and or sub panel. The electrical load calculation means adding up the amperage to all your fixtures and appliances. For safety reasons, it’s always a good idea to build a margin of safety. Usually, the load shouldn’t exceed 75% 80% of your electrical service capacity, how or how ever, in order to do the calculation, you’ll need to understand watts, volts and amps, as well as the relationship between them. You will need the suggested numbers from the NEC code. And if you’re aspiring electrician, Please familiarize yourself with chapter two of the National Electrical Code Book. All right, and you know, so amps equals watts divided by volts, or volts times amps equals watts. All right, so do your calculation. Once we’ve added up the capacity of all the branch circuits, or your home’s of your home’s electrical service entrance, you can proceed to measure it against the proposed load, add the wattage ratings up your appliances and fixtures, and consider the appliances that you will be operating at the same time. You don’t need to add every light bulb and all the plug in appliances you don’t every breaker does, you don’t go in there and add you know I’ve got a hunt. I’ve got 1020 amp breakers and to 40 amp double pole 40 amp breakers to 30 Double Pole breakers and a 50 double pole breaker. So that ends up to 400 amps or whatever it comes up to I’m not looking at the math, but the whole point is you’re not going to be running all of his equipment at the same time, you’re not going to be running the heat at the same time you’re running the air conditioner. However, you know there’s a good possibility that the air conditioner will be running while your hot tubs go in. And if you have an electrical electric vehicle, you might be charging the car saying so. One One method of sizing the electrical service is start by adding the branch circuits you know the the lighting load that’s what the code wants you to do. You add the wattage of all the plug in outlets add the wattage and the National Electrical Code gives you a flat rate per square foot. Right and it’s it’s three volt amps. Okay, so I’m I’m sitting here and I’ve got the document pulled up here how to do the load calculation on your residence. So general lighting in receptacles is three volt amps per square foot, small appliance circuits you got to have at least two that’s 1500 volt amps each additional Platts small appliance circuits one minimum required for your laundry circuit which is 1500 volt amps and if you have a bigger home with another laundry circuit or multiple laundry circuits, one and 1500 volt amps apiece, the dishwasher gets 1200 volt amps the garbage disposal 800 volt amps the microwave would be the Volta amps formula. From the microwave itself same for the trash compactor. to refrain refrigerator has its own circuit and calculation. The range cooktop oven if you have multiple ovens that would be included there. Your dryer, your water heater, possibly a pool pump, or a spa and the vehicle chargers and then you add the sum of all of that
