Within-Sight Disconnect Rules for Equipment

Why this matters

The within-sight rule exists for one person: the tech standing at a condenser, a pump or a water heater with a hand inside it. If the only way to kill that equipment is a breaker in a panel he cannot see, somebody else can turn it back on while he works. It is a common trim-out failure, and it fails for two opposite reasons: a disconnect left off because "the breaker is right inside", and a lock-off clip bolted onto a breaker for equipment whose article never offered that alternative. This card sorts out where the rule applies, what counts as "in sight", and where a lockable breaker is a legal substitute and where it is not.

Code citations here are to NEC 2023 (2020 where the section moved), as adopted by your jurisdiction, with local amendments checked. Permits and the final call on edge cases belong to the AHJ.

The definition, both halves

Article 100 defines "In Sight From (Within Sight From, Within Sight)" as visible AND not more than 50 ft distant from the equipment. Both halves have to be true at once.

• Visible means a person at the equipment can see the disconnect. A wall, a closed door, a corner or a floor between them breaks it, whatever the distance. Two feet through a foundation wall fails.
• Not more than 50 ft means a disconnect in plain view across a long warehouse or a big yard still fails at 60 ft.

The definition does not say whether 50 ft is a straight line or a walking path. Most inspectors measure the straight line between the two, and nobody accepts a disconnect that is 40 ft away in a straight line but only visible by walking around a building. A sight line through a window is an AHJ call; many reject it because a window can be curtained, frosted or painted over later, and the rule is meant to hold for the life of the install.

Where the rule reaches, by article

Three articles carry most of the residential and light-commercial work. They are written differently, and the differences are the whole point of this card.

Read the AC row twice. Air conditioning is where most bad lock-off installs live. A tech who has fed water heaters off a lockable breaker for years carries the habit to a condenser, and 440.14 does not offer it outside an industrial process. The disconnect goes at the unit, on it or within it if it is not on a panel designed for access to the unit and does not cover its nameplate.

What "lockable" means under 110.25

Where an article does allow the lockable alternative, 110.25 decides whether your hardware qualifies. In substance: the provision for locking must be installed on or at the switch or breaker itself and stay in place whether or not the lock is installed, which rules out a portable means of adding a lock.

That rules out the loose clip-on lockout device from your LOTO kit. It is a fine piece of lockout hardware for the day's work, and it does not make the breaker a disconnecting means, because it leaves with the tech. What qualifies is a lock-off attachment that the breaker manufacturer lists for that breaker and that is fastened to it or to the panel cover so it stays there. When the panel maker does not list one for that breaker, you do not have a lockable breaker; you have a disconnect to install at the equipment.

The rule on one house

A ranch on a full basement. The panel is on the basement's back wall. Three pieces of equipment, three different answers.

 BASEMENT, unfinished               WALL    OUTSIDE
                                      |
 [PANEL] ---- 28 ft, clear ---> [WH]  |
    |   visible, under 50 ft: OK      |
    |                                 |
    +--------- 18 ft ----------------X--> [CONDENSER]
      under 50 ft, but the wall       |        |
      blocks the view: NO             |      4 ft
                                      |        |
                                      | [AC DISCONNECT]
                                      |  on outside wall,
                                      |  visible: OK

The water heater. A 4,500 W, 240 V element heater sits across the open basement. It is a permanently connected appliance well over 300 VA, so 422.31(B) applies. Standing at the water heater, the panel is in plain view and the tape reads 28 ft. Visible and under 50 ft: the 2-pole breaker is the disconnect, and nothing more is needed. If the owner finishes the basement and puts a utility-room wall between them, the same breaker stops qualifying the day the drywall goes up, and the fix is either a disconnect at the heater or a listed lock-off attachment fitted to that breaker.

The condenser. The straight-line distance from the panel to the condenser is 18 ft, closer than the water heater, and it fails, because the foundation wall is between them. 440.14 gives no lockable-breaker route for a house, so a disconnect goes on the outside wall within sight of the unit. This one is mounted 4 ft from the condenser, readily accessible, not behind the unit, and not on the unit's access panel. How to Wire an AC Condenser Disconnect and Whip covers the install itself.

What the tech at each unit gets. The water heater tech walks 28 ft to a breaker he can watch while he works. The condenser tech pulls a disconnect 4 ft away. Neither has to trust a stranger upstairs not to flip something on.

How the three articles differ in their logic

The articles are not three phrasings of one rule. They protect against different events, which is why the alternatives differ.

• 440.14 protects a person inside a unit that can start on its own: a thermostat call, a time-delay relay expiring, a compressor contactor pulling in. The code's answer is a switch you can put your hand on, every time.
• 430.102 protects against driven machinery starting while someone is in it: a belt, a pump impeller, an auger. It wants a disconnect in sight of both the controller and the motor, and its exception is narrow and conditional, because a motor 200 ft from its starter is a real hazard.
• 422.31 covers appliances that mostly do not start themselves in a way that catches fingers: a water heater element, a range, a dishwasher. That is why it alone gives the lockable breaker as an equal alternative rather than as a narrow exception.

When you are unsure which article governs, ask what the equipment is. A condenser is Article 440 equipment even though it has a motor in it; 440 modifies the motor rules for hermetic refrigerant compressors. A pool pump is a motor (430) inside Article 680's requirements, covered in Pool + Spa Electrical (NEC Article 680) and How to Wire a Pool Pump Motor Circuit.

Where the habits go wrong

A breaker "right inside the door". A garage panel 10 ft from an outdoor condenser, behind a closed overhead door, is not visible from the condenser. Distance is never the only half.

Lock-off clips counted as disconnects. Fine on a water heater only if the clip is the manufacturer's listed attachment, fastened to stay. A loose clip in a drawer does nothing.

A disconnect hidden by the equipment it serves. A disconnect behind the condenser, reachable only by moving the unit or squeezing between it and a fence, is in sight but not readily accessible, and 440.14 requires both. It also needs its own working space under 110.26.

Disconnects mounted on the unit's service panel. 440.14 permits a disconnect on or within the equipment, but not on panels designed to allow access to it, and not where it obscures the nameplate. A disconnect screwed to the removable side panel comes off with the panel.

Cord-and-plug units unplugged from behind something. A plug counts as the disconnect only if it is accessible. A window unit whose plug is behind a dresser is technically compliant on day one and useless in practice; say so on the ticket.

What changes the answer

• The building changes. A finished basement, a new fence, an added deck or a shed in front of the unit can break a sight line that was fine at final. The rule applies to the installation as it stands, so an alteration that blocks the view needs a disconnect added.
• Commercial and industrial sites. On a rooftop unit the disconnect is at the unit for the same 440.14 reason, and the 430.102 exception becomes reachable only under its stated conditions, which a small commercial site with no written procedures usually does not meet.
• A local amendment. Some jurisdictions require a disconnect at every water heater regardless of 422.31, or every piece of mechanical equipment regardless of sight lines. Check the adopted amendments before you quote the lock-off route.
• The manufacturer's instructions. Some appliance installation instructions require a disconnect at the unit even where the code would accept the breaker. 110.3(B) makes the listing instructions part of the install.

How to check it on a job

Stand at the equipment, at the spot a tech would kneel to work on it. Can you see the disconnect without moving? Tape the straight-line distance and write it on the ticket next to the equipment name ("WH 28 ft clear, breaker 7/9"). For a lockable breaker, confirm the attachment is listed for that breaker, fastened, and stays put with no padlock in it. For an AC disconnect, confirm it is outside the unit's access panels, the nameplate is readable, and you have working space in front of it. Label the disconnect with the equipment it serves.

References

• NFPA 70, National Electrical Code, 2023 edition (2020 where noted), as adopted by your jurisdiction: Article 100 "In Sight From", 110.3(B), 110.25, 110.26, 422.31, 422.33, 422.34, 430.102, 440.14
• See related: How to Wire an AC Condenser Disconnect and Whip
• See related: How to Wire an Electric Water Heater Circuit
• See related: Pool + Spa Electrical (NEC Article 680)
• Equipment manufacturers' installation instructions and breaker manufacturers' listed lock-off accessories