Hello, this has to be one of the best videos I have seen describing an issue we amateurs face when installing receptacles or lights in a new garage or shed. Thank You so much, well done. Best Regards. 👍
Good explanation. Also, for the hobbyists out there, keep in mind that these calculations are for a circuit with only light fixtures. If you put anything else on that circuit, you’ll need to subtract that load to see how many fixtures you can add.
You can only have 12 total devices if you're mixing lighting with receptacles. How do you subtract a load from a lighting circuit when you have no clue what will be plugged in there in the future. These calculations are for KNOWN lighting loads ONLY.
@@That90sShow I never specified that receptacles would be on that circuit-it could be anything that draws power. My point was making sure folks not familiar with electrical work understand that if you add other elements to the circuit, the calculations change. Your number of 12 is also arbitrary-that would depend on the circuit amperage, draw of the fixtures, whether you have open receptacles or fixed loads, etc.
Thank you!! Total electrical dummy but want to understand RV electricity and this video just “made the light bulbs come on” for me 😂 Really appreciate this!
Clean, clear, direct, concise and to the point. You also have a good voice for explanation. Now I know something I didn't before I viewed this video. Cheers 🍻
Exactly the info I was looking for! Pairing this with the other video you put up about outlets on a circuit, this is just what I needed. Thank you for the info!
Nice presentation . Simple and complete compared to what I learned back years ago . At that time when the instructor would illistrate the formula he would over complicate the calculations , doing too much math in the formula . Cheers 03/05/2022
I once lived in an older apartment that put EVERY light on one 20A breaker. Might have been needed when that wiring was done - but with my mix of LED and compact fluorescents, it was SEVERE overkill. I talked the owner/manager into adding a 15 amp duplex outlet to the circuit, as that place was WAY short on outlets.
Yes it did, thank you. At 67, Me, forgetting things that I had once learned makes me dangerous or a procrastinator. Now, using your info, I can finish up the wiring that I have allowed to mushroom by unsureness and to finish my music/woodworking barn with confidence. Once and for all. If you have ever said that you hope that you've helped one person, I am that guy. 🤠
FYI Building Codes are public domain and can be accessed online from numerous legal libraries. Call your local building department and ask them what Code governs your jurisdiction, and look up the residential electrical code requirements for branch circuits, etc. FYI, adding new lights and receptacles is easy renovation work, but if it isn't done right and to your local Code requirements, you can burn down your home or even electrocute yourself. If you have zero experience, hire an Electrician.
Great! This is exactly what I need to know. Gonna be lighting up a basement and I don’t know how many lights I need or how many light to put on a circuit.
Great video, especially as it helps me understand how my 75 year old house was wired. One observation however - the word is "continuous," not as you have it, "continuos" (@3:45).
This is a great example but these days many people are getting away from the old screw base fixtures because you can still find bulbs of 150 watts and more. (yes, still out there) If you install NON screw base fixtures they will likely be a specialty base that can't accept larger bulbs and will be under 20 watts draw each. IOW, you have the added benefit of no fire hazard due to wrong bulbs overheating. Still, the math works out and it really is that simple.
Solar lighting has major potential market out there. Imagine basement lighting. No more scary basements. We dont live with basement anymore, but our north facing kitchen/living room got me into solar LED lighting. Plus, I love our bathrooms well lit for long long hours. Bright bathroom looks very clean.
In the UK we use 230 volts. To answer your question in the UK we assumed total load and divide by 230 to get Amps , ie assume you want to install 12 lights on a 5Amp circuit with a 6amp MCB and the lamps are 100w each that would be 1200w divide by 230 = 5.2Amps , that’s the design current the circuit protection device should be equal to or greater than the design current. As you can’t get a 5.2Amp MCB You will need a 6amp MCB. This is international no matter what the nominal voltage is.
We currently have a Federal Pacific Stab-Lok breaker panel that we're planning on having replaced. After it's replaced, I do want to separate some circuits. I also want to put all the overhead lights in our house on one 15 amp circuit. All our lights are LED and even if our lights were all 100 watts, they would still not exceed 15 amps.
If you're wiring a house from scratch that is one way you can do it but typically every light in a house is off of a outlet. The reasoning for this is to reduce the amount of wire that is needed to wire the entire house. At today's costs I would not want to wire out that way as 12/2 is about $150 for a 250ft roll now.
We have a 15 amp breaker running from the house to a tool room, then by knob & tube overhead open wire to a carriage barn to a 2 car older garage to a large chicken coop/workshop. Along the way there are many lights, many outlets with multiple power strips, animal water de-icers, electric woodshop tools, and now outdoor blow up Christmas decorations requiring continuous running fans. Yeah...the 15 is tripping.
Perfect math if you were utilizing incandescent lamps as you stated. The problem is then you show fluorescent fixtures and say, now you know how to calculate how many lights. Not so fast! Fluorescent lamps have wattages on them, but you do not just add them up. In order to do these luminaires, you must look at the ballast information and find “line current” number and multiply by voltage to get VA(let’s call it watts). Best wishes! Kevin
@@BevinsBuilds My mistake. You should still find line current instead of using watts for those LED’s. Although not nearly as bad as fluorescent, there is still a very small amount of losses in the drivers. Thanks for the clarification!
What happens in a series parallel circuit. (Some led light bars daisy chain in series.). I think I want to daisy chain 4 light pairs (in series), but set each pair in parallel.
You figure Watt load from lights used. Then 80% rule of watts on circuit for continuous use. Don't have to follow rule for lights not in continuous use. Continuous use defined .... 2 hrs ? and more... commercial use mostly. Warehouse, mfg areas, hallways, offices. A house...no.
Daaaamn Sam!! I know your name isn't Sam It just ryhmes with damn and sounds cool... But nice video sir.Very informative and easy to comprehend. Of course the 15 amp circuit would be using 14/2 wire and the 20 amp circuit would be using 12/2 wire. Now if you're using led lights, you can probably use more lights per circuit because led's consume alot less power than incandescent lights right?
If installing fluorescent fixtures , You have to add the wattage of the fluorescent tubes plus the wattage of the ballast , For example , A 4 foot two bulb fluorescent fixture would draw around 180 watts , The average wattage of two 4 foot fluorescent tubes is 80 watts plus the wattage of the ballast , Another thing is that if you go with LED light fixtures , You can add alot more fixtures because of how much less watts they use than fluorescents and incandescent fixtures Just use the same calculations shown in the video , Definitely best to go with LED fixtures and avoid fluorescent , Mercury vapor or other fixtures that have a ballast because they use more power than even incandescent fixtures Plus with LED fixtures , You won't have the troubles with LED fixtures compared to fluorescents and other fixtures that have a ballast , Plus LED fixtures and bulbs are coming down in price , Now if you have fluorescent fixtures and want to convert them to LED tubes , It's best to get the direct wire LED tubes for saving energy costs The plug and play LED tubes use the existing ballast which is not practical because you're using power to operate the ballast which draws much more power than the direct wire LED tubes The direct wire LED tubes don't use a ballast , So they use alot less power than the plug and play LED tubes For example , Two 4 foot direct wire LED tubes will draw only 32 watts of power compared to the plug and play which use the existing ballast which draws 100 plus watts
Thanks. This applies to computers also. So I should be careful and perhaps NOT get the new 4090 Graphics card and a new 1,600 watt power supply to put in the office, unless I put it in the dining room where we have a 20Amp circuit. Luckily it is a nice piece of decoration! And we can dine by the computers' RGB-light so we don't trip the breaker!
The electrical in the house I bought is a mess. My question is can I dedicate one circuit for each room? For instance my master bedroom has seven outlets and two ceiling light fixtures. Assuming the light fixtures were rated for 100 w each could I put all of this on one breaker?
Yes, thats how electrical contractors do it. One circuit for each room is the best practice. Just remember the kitchen, bathroom and garage lights and receptacles can't be mixed on one circuit.
Then...why do heaters seem to have a 1500w limit when I go look to buy one? I know they say don't put 2 on the same circuit (because that's going to trip the breaker every time), but even the 1500w is above the 80% limit mentioned.
That's a good question. Ideally these heaters should be used only on a 20 amp circuit, but many homes have 15 amp circuits in rooms where heaters are likely to be used. If nothing else is on the circuit you should be okay because you're barely above the 80% limit. I wouldn't leave one on when sleeping, though.
