Control Devices and Disconnecting Means: Where Every Disconnect Goes and How It Is Rated
This area is small on the blueprint (Journeyman 1 + 1, Master 3 + 1, Residential 2) but it is a synthesis area — PSI pulls its disconnect questions from Articles 110, 225, 230, 404, 422, 424, 430, 440, 445 and 450. This lesson collects every disconnect rule in one place and adds the control-circuit rules that ride with them. All numbers are cross-referenced to the lessons where the primary text was read. Written from the 2026 text.
NFPA 70 National Electrical Code, 2026 edition · Reviewed 2026-09-19
This area is small on the blueprint (Journeyman 1 + 1, Master 3 + 1, Residential 2) but it is a synthesis area — PSI pulls its disconnect questions from Articles 110, 225, 230, 404, 422, 424, 430, 440, 445 and 450. This lesson collects every disconnect rule in one place and adds the control-circuit rules that ride with them. All numbers are cross-referenced to the lessons where the primary text was read. Written from the 2026 text.
1. Two definitions the whole area depends on
- In Sight From / Within Sight (110.29, new location in 2026): visible and not more than 50 ft (15 m) from the equipment.
- Lockable open (110.25): where the Code requires a disconnect to be lockable in the open position, the provisions for locking remain in place with or without the lock installed (portable means such as a lock-off clip that stays on the breaker qualify; a cord-and-plug connection is the one exception). Most "within sight" rules have an exception that accepts a lockable disconnect instead — but not 440.14 for HVAC in general occupancies and not 430.102(A) for controllers.
This is where the public part ends.
The rest of this lesson, its quiz, all 2 lessons in the module and every mock exam open with the 7-day pass for $9. If you stay, it comes off lifetime.