A panel schedule is the only document that explains your work to the next electrician. It is also one of the easiest things on a job to get written up for, because the inspector can evaluate it standing still, in thirty seconds, without a meter.
Here is how to fill one out so it does its job and passes the first time.
Start with the panel header, not the circuits
Before you touch a circuit line, the schedule needs to say what panel this is. Six fields, and most corrections come from skipping them.
| Field | Example | Why it matters |
|---|---|---|
| Panel designation | LP-2 | Distinguishes it from every other panel in the building |
| Location | Basement, NE corner, mech room | Someone has to find it in a hurry |
| Fed from | MDP, circuit 14, 100A | Required by 408.4(B) outside one and two family dwellings |
| Voltage and phase | 120/240V, 1Φ, 3W | Determines everything downstream |
| Bus rating | 200A | Not the same as the main breaker |
| Main | 200A MCB, or MLO | Main breaker versus main lugs only |
Bus rating and main rating get conflated constantly. A 200 amp bus with a 125 amp main is a normal and legitimate arrangement. Writing 125 in both boxes tells the next guy he cannot upsize the main when in fact he can.
Number the circuits the way the panel is actually built
Standard North American panelboards number odd circuits down the left and even circuits down the right. Circuit 1 is top left, circuit 2 is top right, circuit 3 is second from top left.
Do not renumber to suit yourself. The numbers are physically stamped or implied by the bus arrangement, and a schedule that disagrees with the panel is worse than no schedule, because the next electrician will trust it.
Phase rotation follows from the bus. In a three phase panel, moving down the left side gives you A, B, C, A, B, C. Circuits 1 and 3 are not on the same phase. Circuits 1 and 7 are.
| Circuit | Phase | Circuit | Phase |
|---|---|---|---|
| 1 | A | 2 | A |
| 3 | B | 4 | B |
| 5 | C | 6 | C |
| 7 | A | 8 | A |
This is why a two pole breaker lands on 1 and 3, not 1 and 2. It needs two different phases, and 1 and 2 are the same phase on opposite sides of the bus.
Write descriptions that survive the next owner
This is where most schedules fail, and the code language is unusually specific about it. NEC 408.4(A) requires every circuit to be legibly identified as to its clear, evident, and specific purpose, in enough detail to distinguish it from all others.
It also says identification shall not depend on transient conditions of occupancy. In plain terms, you cannot label a circuit by who happens to live there.
| Do not write | Write |
|---|---|
| Bedroom | Bedroom 2 recept, north and east walls |
| Kids room | Bedroom 3 recept and lighting |
| Kitchen | Kitchen SABC #1, counter recept south |
| Lights | 1st floor hall and stair lighting |
| Outside | Exterior recept, front porch, GFCI |
| Furnace | Gas furnace and condensate pump, basement |
The test is simple. Could someone who has never been in the building stand at the panel and know what to shut off? If the answer is no, the description is not specific enough, whatever it says.
Multiwire branch circuits need special handling
A multiwire branch circuit shares a neutral between two ungrounded conductors on different phases. On the schedule, both circuit numbers need to show the connection, because the next person has to know that killing one leg does not de-energize the neutral.
Note them as a pair. Circuit 7 reads "Kitchen SABC #1, MWBC with 9" and circuit 9 reads "Kitchen SABC #2, MWBC with 7."
NEC 210.4(B) requires a means to simultaneously disconnect all ungrounded conductors of a multiwire branch circuit at the point where it originates, which in practice means a two pole breaker or an approved handle tie. If you are writing MWBC on the schedule, there had better be a handle tie behind the dead front.
Record the device, not just the amperage
A 20 amp breaker and a 20 amp AFCI breaker are not interchangeable, and the next electrician replacing one needs to know which he is buying before he drives to the supply house.
Use short consistent notation in a breaker column: 20A for standard, 20A AF for arc fault, 20A GF for ground fault, 20A DF for dual function, 2P 30A for a two pole. Whatever shorthand you pick, use it the same way on every schedule you ever write.
Fill it out at rough, correct it at trim
The schedules that end up blank are the ones that were going to get done at the end. Pencil in circuit assignments at rough when you know what is feeding what, then correct and finalize at trim after the inevitable changes.
Typed beats handwritten if the panel will ever be inspected by someone who did not watch you install it. Our free panel schedule template is an Excel sheet with the header fields and numbering already laid out, and it prints to fit a standard panel door.
Before you close the door
Four checks, about ninety seconds total.
- Every position on the schedule matches a position in the panel, including blanks
- Every two pole breaker spans two phases, and the schedule shows both numbers
- No description depends on who currently lives there
- Spares say spare and spaces say space
What NEC 408.4 requires in full, including the source of supply marking that catches people on commercial work, is covered in panel schedule requirements under NEC 408.4.