Power Control Systems Just Made Load Calculations a Lot Less Painful

Doing load calculations can be a bit of a slog. Adding up the water heater, the dishwasher, the EV charger, and all the other loads, then working through the math for branch circuits, feeders, and services – it’s typically not anyone’s favorite part of the job. Lucky for us, the 2026 NEC has an easier path for practitioners working with power control systems (PCS).

Building on their earlier conversation about PCS technology, HeatSpring instructor Rebekah Hren walks through another significant change in the 2026 code. What used to be Article 220, the go-to article for load calculations, was moved into chapter one and renumbered as Article 120, right alongside Article 130 on energy management and PCS. That placement was intentional.

Article 120.7, which appeared in the 2023 code but is significantly clearer in the 2026 version, allows practitioners to use a PCS set point to perform load calculations. Instead of tallying individual loads, you have one number: your PCS set point. The underlying logic is that power control systems can be trusted to provide overload protection for conductors and to control power sources, which is what makes that simplified approach possible.

For designers and installers, this shift makes an often frustrating part of the job considerably more straightforward.

Rebekah and her Solar Tech Collective colleagues cover Articles 120, 130, and much more in “Comprehensive2026 NEC Requirements for Electrotech: PV, ESS, EVs, PCS, and More,” available now on HeatSpring.

Enroll here!

Transcript below. 

One interesting development ties directly back to what we were just discussing about power control systems.

Something interesting that happened is that what used to be Article 220, which covers load calculations for branch circuits, feeders, and services, got moved up into chapter one. Again, that’s a signal: this is something really important. Along with that move, 220 became Article 120. That’s where we go to do load calcs now.

For those of you who have done load calcs, you may know them as tedious, confusing, and not any fun at all. All of that is still true, except that there’s a new allowance in Article 120, specifically 120.7. It was in the 2023 code, but it’s a lot more clear in the 2026 code. It allows you to use a power control system set point to do load calculations, and it makes load calcs really straightforward if you have a power control system.

So along with moving Article 750 up into Article 130, you now have Article 120 for load calcs and Article 130 for PCS sitting together in chapter one. That’s intentional. You can use the PCS set point to do load calcs, and you’ve got one number. Instead of going through and adding up what’s the water heater, what’s the dishwasher, what’s the EV charger, your PCS set point, say 60 amps, is your number.

It works because we trust that power control systems are going to provide overload protection for conductors and control power sources. That’s what makes the simplified approach possible. It’s something pretty new and interesting, and you can see it in the way these articles are changing in the code. It also gives us a much easier path to load calculations.