Hi all,
Today is the day I ask a random question that comes to my mind every now and then — Is there a reason why electrical service panels are designed to have the primary service conductors and main switch inside the panel? Wouldn’t it be safer to work in the enclosure if the switch was upstream?
– Mike
Prescriptive codes don't address the connection at less common angles, so base the connection off more typical ones using bolts, structural screws, blocking, and steel tension ties.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
That is a great question for the electrical engineers who design them. Working safely on a non-energized panel is a big reason I like a main disconnect outside the house. Firemen also like this.
Maybe the engineers can also say why they make the ears on electrical outlets and switches so small.
money money money.
It is less expensive to by and install one box.
Also, most places you can pull the meter to disconnect.
Thanks, guys! I figured about as much.
This set up is called a main breaker panel. The feed runs directly to the main breaker which has to be turned on to energize the bus. There is no danger working in the panel if the main breaker is off. A panel without a main breaker is a main lug panel. The feed runs to lugs on the bus which is always energized unless the panel is disconnected remotely. The disconnect needs to be within sight of the panel. If you have a disconnect outside the house and a panel inside you still need a main breaker. Main breaker panels are very safe and convenient. Most utilities seal or lock the meter so that it cannot be pulled without their knowledge or permission.
The primary reason for designing electrical service panels with the main switch inside the panel is to provide a centralized location for controlling the power supply to the building. Having the main switch inside the panel allows for easier access and maintenance by electricians and service personnel. Additionally, placing the switch upstream would require separate enclosures for each circuit, increasing complexity and cost. While safety is a consideration, proper precautions and procedures are in place to ensure the safety of those working on electrical panels, regardless of the switch's location.