Practice: fastened appliance demand load
Each problem uses new numbers, so you practice the method rather than memorizing an answer.
Pick the answer: sizes and ratings come from your code book.
Worked solution
Formula
| Symbol | Meaning | Unit |
|---|---|---|
| n | Number of fastened-in-place appliances that qualify | |
| Sum | Total of their nameplate ratings | VA |
Worked example
A one-family dwelling has these loads on its service: water heater 5,500 W, dishwasher 1,300 VA, disposal 800 VA, trash compactor 800 VA, built-in microwave 1,400 VA, a clothes dryer rated 5,500 W and an EV charger (EVSE) rated 48 A at 240 V. Using the standard method and 120.53, what is the demand load for the fastened-in-place appliances?
- Leave out the dryer (120.54) and the EVSE (120.57). They have their own rules and are not in the 120.53 group.
- Fastened appliances: water heater, dishwasher, disposal, trash compactor and microwave = 5 appliances.
- Add the nameplates: 5,500 + 1,300 + 800 + 800 + 1,400 = 9,800 VA.
- Five is four or more, so take 75% (120.53): 9,800 × 0.75 = 7,350 VA.
Answer: 7,350 VA
Fastened appliance demand load, explained
Section 120.53 (220.53 in 2023) gives dwellings a break for small fixed appliances that seldom all run together. When a service or feeder supplies four or more appliances fastened in place, you may take 75% of their combined nameplate rating. With three or fewer, use the full total.
The trap is deciding what counts. Typical members of the group are the water heater, dishwasher, disposal, trash compactor and a built-in microwave. Each one must be at least 1/4 hp or 500 W to count. Leave out the range and other cooking units (120.55), the clothes dryer (120.54), electric space heating, air conditioning and EV supply equipment. Those are calculated by their own rules.
Watch the voltage when an appliance is given in amperes. A 120 V dishwasher drawing 10 A is 1,200 VA; multiplying by 240 V doubles it by mistake. A 240 V water heater is still a fastened appliance and still counts toward the four.
Open 120.53 when a question lists a mix of loads. Count only the qualifying appliances first, then decide whether the 75% applies.
How to solve it on the exam
- List every appliance in the question.
- Cross off the range, cooktops and ovens, dryer, space heat, AC and EVSE.
- Convert any ampere ratings to VA with the appliance voltage (120 V or 240 V).
- Count what is left. Four or more: take 75% of the total. Three or fewer: use 100%.
Common mistakes
- Counting the dryer or range as the fourth appliance to reach the 75% factor.
- Including the EV charger or air conditioner in the group.
- Applying 75% to only three appliances.
- Multiplying 120 V appliance currents by 240 V.
- Leaving out the water heater because it is a 240 V load.
Exam tips
- Draw a quick two-column list on the notepad: "counts" and "own rule". It makes the count of four obvious.
- This rule did not change in 2026, but the section number did. If your old notes say 220.53, it is 120.53 in the 2026 book.
Fastened appliance demand load calculator
Questions people ask
What appliances count for the 75% demand factor?
Fastened-in-place appliances in a dwelling, such as water heaters, dishwashers, disposals, trash compactors and built-in microwaves, each rated 1/4 hp or 500 W or more. Ranges, dryers, space heat, AC and EV chargers do not count.
How many appliances do you need for the 75% demand factor?
Four or more on the same feeder or service. With three or fewer, use 100% of the nameplate total.
Where is the 75% appliance rule in the 2026 NEC?
Section 120.53. It was 220.53 in the 2023 NEC.
Sources
- TDLR: Electrician examination information
- PSI: Texas electrician Candidate Information Bulletin
- Mike Holt: Electrical Exam Preparation, 2026 NEC, Unit 6 sample (free PDF)
- NFPA: 2026 NEC Second Draft report, Code-Making Panel 2 (Article 120)
About the tables: The exam is open book. These problems cite the 2026 NEC section and table so you practice finding them in your own book. We never print NEC text or tables.