NEC restores 705.11 conductor limits

Solar installers use a supply-side tap when they need to connect generation ahead of the main breaker — basically between the utility service and the service disconnect. It is the workaround for homes and buildings where a normal load-side breaker connection will not fit. The problem is that this method puts energized conductors in a touchy part of the system, so conductor routing and overcurrent protection matter a lot. In the 2026 NEC, Section 705.11 brings back explicit distance limits that had disappeared in the 2023 code, and that changes real design choices again. (mayfield.energy) ### What is a supply-side connection? It is a connection from a power source — usually solar, sometimes storage or other distributed generation — to the service conductors or service equipment ahead of the main service disconnect. People also call it a line-side tap. You use it when the main panel cannot accept more backfeed on the load side, or when the service equipment layout makes a load-side interconnection impractical. (expertce.com) ### Why do these conductor lengths matter? Because the stretch of conductor between the tap point and the first overcurrent protective device is the risky part. The longer that unprotected run is, the harder it is to control fault exposure and physical routing inside a building. The code is trying to keep that segment short, direct, and easier to protect. (mayfield.energy) ### What exactly changed in 2026? The 2026 code restores clear maximum lengths for these runs. In dwelling units, the overcurrent device must be within 10 feet of conductor length from the point of connection to the service conductors or equipment. In occupancies other than dwelling units, the limit is 16.5 feet. (mayfield.energy) wall. (electricallicenserenewal.com) ### Weren’t those limits already there? They were in the 2020 NEC, then they vanished in the 2023 edition, which created a lot of confusion in the field. Designers still had to satisfy other protection and wiring-method rules, but the simple bright-line distance cap was gone. The 2026 cycle reverses that and, in practice, brings back the older constraint with clearer placement language. (mayfield.energy) ### So what changes for solar design? Layout matters more again. If the meter, service conductors, and disconnecting means are spread out, a supply-side interconnection may no longer pencil out unless the overcurrent device can be placed close enough to the tap. That can push a project toward different service equipment, a dedicated interconnection section, or a load-side redesign instead of a simple line-side tap. (mayfield.energy) ### Does this hit homes differently than commercial jobs? Yes. Homes get the tighter 10-foot limit, while non-dwelling occupancies get 16.5 feet. That sounds small, but in residential retrofits a few extra bends through service equipment can eat up distance fast. Commercial gear often has more room and more purpose-built interconnection options, even though the rule is still restrictive. (electricallicenserenewal.com) ### Is this just a technical cleanup? Partly, but not only that. The 2023 deletion left installers and inspectors with less explicit guidance on one of the most sensitive parts of a distributed-generation interconnection. Restoring the limits makes plan review more predictable, but it also removes some flexibility people may have assumed they had over the last code cycle. That is the real practical effect. (mayfield.energy) ### Bottom line This is a code edit, not a market shock. But for anyone designing or approving supply-side solar connections, it is a meaningful one. The 2026 NEC basically says the unprotected run has to stay short again — 10 feet in dwellings, 16.5 feet elsewhere — and that will decide whether some projects stay simple or need a different interconnection strategy. (electricallicenserenewal.com)