During a recent training program on the National Electrical Code (NEC), a question arose about panelboards and whether they could be installed in a horizontal orientation rather than vertically. This has come up often, probably due to various home-improvement broadcasts that are produced in Canada. Another question came up about circuit breakers in panelboards and whether they can serve as the required motor disconnecting means as specified in 430.102(B). Specifically, is a means to lock the breaker in the open position required in the panelboard?


Panelboard breaker orientation


The answer to the panelboard breaker orientation question is no, unless all the breakers in the panelboard are orientated so the down position is the off position and the up position is the on position. Listed panelboards are typically manufactured to be installed so the contained breakers operate horizontally rather than vertically. 


The on and off positions are required to be clearly indicated on the breaker. Note that NEC Section 240.81 does not permit breakers installed in the vertical position to have the down position be the on position.


Panelboards are typically evaluated and certified (listed) to UL 67 Standard for Panelboards. Therefore, the manufacturer’s installation instructions may specifically require the panelboard installation position to conform to the product standard and the NEC. This often means that the top position of the equipment needs to be up. See NEC Section 110.3(B).


To a degree, this issue also relates to safety. Electricians generally understand the down position of any switch or breaker as the off position. Keep in mind that it does not require all switches and breakers to be installed vertically rather than horizontally, but, if they are, the rules require the up position to be the closed or on position. As a reminder, qualified workers should always apply required safety-related work practices in NFPA 70E when implementing lockout/tagout programs.


You may also want to be aware that the Canadian Electrical Code (CEC) Part I does not contain a similar restriction. You may have seen some Canadian television programs on HGTV that show residential panelboards installed horizontally, but Canada regulates the issue differently. Refer to the CEC Part I for specific information. My answer assumes that the question relates to an installation covered by the NEC.


Breakers as disconnecting means


For the question of circuit breakers serving as disconnecting means, the answer is generally yes, but there are a few conditions that must be satisfied. The general requirement for disconnecting means at motors is that the means be installed within sight from the motor and driven machinery location. 


NEC Article 100 defines the term “within sight from” and includes the phrase “the specified equipment is to be visible and not more than 50 feet distant from the other.” Both criteria must be satisfied. If the distance between the breaker and the motor does not exceed 50 feet and the motor is visible from the breaker location, the provisions for locking means at the breaker are not required. However, if the distance is greater than 50 feet or the motor is not in sight of the breaker, the exception to 430.102(B)(1) is permitted, provided the 110.25 requirements are satisfied. These conditions trigger the requirements that the disconnecting means is required to be lockable open; it shall be capable of being locked in the open position. The provisions for locking shall remain in place with or without the lock installed. 


Panelboard manufacturers and breaker manufacturers produce accessory features that can be installed to achieve this lockable disconnecting means at the breaker. Remember that a lockable door on the panelboard does not meet the minimum requirements for lockable disconnecting means.


In summary, breakers installed vertically and not horizontally must be installed so that the up position is the closed, or on, position. Breakers installed in a panelboard can serve as a motor disconnecting means required by 430.102(B)(1) as long as the disconnecting means is within sight from the motor location. If the disconnect (breaker, in this case) is not within sight from the motor, the lockable provisions in 110.25 are permitted if all the conditions provided in 110.25 are satisfied. Always verify with the authority having jurisdiction that there are no other local code rules that may be more restrictive than the NEC.