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Frequently Asked Questions (FAQ) about Electrical Panels

Monday, June 7, 2021

Electrical panels are still called “fuse boxes” by many homeowners, although the fuses have long-ago been replaced by circuit breakers, and new technology like AFCI and GFCI added to many breakers. Here’s some of the questions we get asked most-often about them:

What is the maximum number of circuit breakers allowed in an electric panel?

Can you add circuit breakers by different manufacturers to an electric panel if they fit?

Why do some wires in an electric panel have tape wrapped around them near their connections?

My circuit breaker won't reset. What's wrong?  

Why is a fuse box/panel an insurance problem for homebuyers?  

Why are old electrical components not always "grandfathered" as acceptable by home inspectors?

What happens when you press the "TEST" button on a circuit breaker in an electric panel?

What is the voltage rating of a house electrical system?

What is a split bus electric panel? 

When should a corroded or damaged electric panel cabinet or disconnect box be replaced? 

Where are electrical breaker panels not allowed by code?

What is a lock device on a circuit breaker for?

What is a reliable way to tell if the electrical service is 3 phase or single phase? 

Why is the circuit breaker stuck in the middle? 

Can an electric panel be located in a closet? 

Can an electric panel be located in a bathroom? 

• What is a "backfeed" main breaker at an electric panel? 

• How do I find out the manufacturer of an electrical panel?

What are the code requirements for an old fuse panel/box? 

What is a tandem circuit breaker?

How dangerous is rust and corrosion inside an electrical panel?

 Are old fuse boxes illegal?

What causes copper wires to turn green or black in an electric panel?  

How far away should a sink be from an electric panel? 

• What is the code required clearance in front of an electric panel? 

Can an electric panel be mounted upside down?

Who is the manufacturer of those "bad" electric panels? 

What is a "missing knockout" or "open knockout" in an electric panel box? Why is it a problem?

Why are Zinsco and Sylvania-Zinsco electric panels a problem? 

• What is the maximum height you can mount an electric panel above the floor? 

What causes a hot circuit breaker in an electrical panel?

What are the code requirements for a circuit directory and circuit identification for an electric panel?

What is the gooey stuff on some of the wire connections in the electric panel? 

What is a "missing twistout" at an electric panel?

Can an electric panel be mounted sideways-horizontally?

What is a double tap at a circuit breaker?

• Where do I find the the main electrical breaker/disconnect to shutoff power for a condominium? 

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