Do Pancakes Violate Code? How Many Conductors can ACTUALLY Fit?

Do Pancakes Violate Code? Absolutely not!! They are delicious! Oh. Not that kind of delicious, syrupy goodness, but rather pancake electrical boxes!! If you have ever had the pleasure to install or perform service with one of these boxes, you know exactly what we are talking about!! On this episode of Electrician U, Dustin takes an adventure to find out if in fact the round pancake boxes we see, as electricians, are code compliant. I know, I know, I was hoping for a road trip for pancakes too!! 😊Show more

🤘⚡️MEMBERSHIP⚡️🤘
JOIN ELECTRICIAN U - become a member and get:
FREE Continuing Education every year
FREE Practice Exams
FREE Monthly Video Courses
FREE Weekly Live Instructor-Led Classes
FREE Monthly Educational Newsletter
Premium Members-Only Content
Private Discord Channel
Monthly Members-Only Discord Chats
Sign up here --- https://www.electricianu.com/electrician-u-membership/

🎧🎹MUSIC AND VIDEO:🎹🎧
https://www.facebook.com/descantmv

🎬✍️ART AND ILLUSTRATION:✍️🎬
https://www.daverussoart.com

First, what would we use a pancake box for? These boxes can be rather handy if you have to install a box for a light fixture with very little clearance behind them. Biggest item that comes to mind is if the fixture needs to be installed directly where a stud is, and we don’t have a void in the wall for a box. You simply install the box to the stud, install your wires and the drywall covers up the depth of the box (as there is no plaster/tile ring) to install. You then would mount your fixture over the box, terminate your wires, and move on to the next task. While this application is handy for placement of the box, it can cause other issues such as not enough wire bending space, pinched wires (due to the shallow depth of the box), and other items.
Article 314.16 of the NEC (and I am paraphrasing here!) that a box shall be sized to provide enough free space for all the conductors in it. Within the article, there are a few areas that provide us with some guidance. B1 covers conductors; so, the wires themselves. B2 covers clamp fill; this is for any INTERNAL connectors (some metallic boxes have these built in and must be accounted for). B3 covers support fittings; some luminaires have a stud that holds the fixture to the box). B4 covers device/equipment; things like switches or receptacles themselves. B5 covers equipment grounding conductors; these are counted separately from the phase and neutral conductors as there can be more of them than any other conductor in certain situations.
Table 314.16(A) and 314.16 (B) are two tables that are used to size some standard boxes as well as some standard conductors. To use Table 314.16(B), simply find the corresponding wire size you are using, multiply by how many conductors you have in the box of that size and deduct for the equipment grounds (we only count them all as 1 conductor until you get to 4, then .25 of an allowance for every other equipment ground over 4). Once that number is generated, compare it to Table 314.16(A) with the box that you are attempting to use. Remember, you must account for devices, internal cable clamps and studs as well! If the number you came up with is larger than the amount for the box you are trying to use, you will have to select a larger box that will fit the number of conductors you need.
The boxes should have their volume stamped in them. 4” pancake boxes have a volume of about 6 CI and 3” pancake boxes have a volume of around 4 CI. Considering that a piece of #12 wire takes up 2.25 inches, that means you could not get a piece of 12-2 Romex into a 3" box. A piece of #14 wire takes up 2 inches so one piece of that cable WOULD be acceptable to put in there, but not if you had a device, a fixture stud, or an internal connector.
So, we can see that for most applications, a pancake box is too small to use for either 12-2 OR 14-2 especially if they have internal cable clamps in the box. So, what are our options? We could select a box without internal clamps, make sure and use 14-gauge wire (provided it worked with the ampacity of our fixture), and place the box at the end of the run and only had the one piece of cable entering it. It is simply a numbers game!
We hope this demystified the pancake box size issue! Please continue to follow Electrician U and Dustin as we are constantly adding new content to help our followers on their careers as electricians!

#electrician #electrical #electricity