How To Look At A House

McGarry and Madsen's home inspection blog for buyers of  

site-built, mobile/manufactured and modular homes


Saturday, October 20, 2018

Here’s links to a collection of our blog posts about "ELECTRIC PANELS":

Why is there a 3-phase breaker in a single phase electric panel with only two bus bars?

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

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

• What does maximum sum of breaker ratings per stab mean in an electrical panel? 

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

Why is spray paint on the bus bars of an electric panel a safety defect?

Why is it unsafe to bond neutral and ground wiring at subpanels?

When was it first required that neutrals and grounds be separated (not bonded) on any panel past the main service panel?

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

What is a tandem circuit breaker? 

When did arc fault circuit interrupter (AFCI) breakers first become required?

Can an electric panel be located in a closet? 

Can an electric panel be located in a bathroom? 

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

What is a split bus electric panel?

How do I identify a combination AFCI (CAFCI) circuit breaker? 

What is three phase electric service?

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

Can a doorbell transformer be installed inside an electric panel?

What does a circuit breaker with a yellow or white test button indicate? 

What is the maximum gap allowed between the front of a recessed electric panel box and the wall surface surrounding it?

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

What are the requirements for NM-cables entering an electric panel box?

Can a washer or dryer be located in front of an electric panel? 

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

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

Why is bundled wiring in an electric panel a defect?

What is the difference between GFCI and AFCI circuit breakers? 

When was the "maximum of six switches or breakers" first required for the main disconnect in a house electrical system?

What is the voltage rating of a house electrical system? 

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 a Dual Function Circuit Interrupter (DFCI)? 

What is the difference between a Combination Arc Fault Circuit Interrupter (CAFCI) and an Arc Fault Circuit Interrupter (AFCI) circuit breaker?  

What is the difference between "grounded" and "grounding" electrical conductors? 

What does it mean when a wire is "overstripped" at a circuit breaker?

Why is there a GFCI breaker in the electric panel for the bathroom shower light and exhaust fan?

Why is an old fuse panel dangerous?  

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

Can an electric panel be mounted upside down?

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

Can multiple neutral or ground wires be secured under the same terminal in an electric panel? 

What is a lock device on a circuit breaker for?

Why is the circuit breaker stuck in the middle? 

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?

What is the right electric wire size for a circuit breaker in an electric panel?

What is the life expectancy of a circuit breaker? 

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

Why do some breakers in my electric panel have a "TEST" button on them?

What is the right size electric panel for a house?   

 The electric panel is marked "Trilliant" and it's all grey plastic. Is it alright? 

What do I need to know about buying a whole house surge protector?

• What is an electrical OCPD?

• Why is an undersized wire between a circuit breaker and a whole-house surge protector device acceptable? 

• Is a refrigerator required to have its own dedicated circuit?

What is the maximum allowed height of a circuit breaker (OCPD) above the floor?

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

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

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

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

When did the code first set a limit of one neutral wire (grounded conductor) connection per lug/set-screw in an electric panel?  

What is the main bonding jumper and where do it find it in an electric panel?

• What is a “bus stab” in an electric panel? 

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

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

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

What causes a hot circuit breaker in an electrical panel?

• Why is the National Electrical Code (NEC) so hard to understand and complicated?

Why is there no main shut-off breaker in my electric panel?

Why did my generator hookup get tagged as defective by the home inspector?

•  Can an unused (spare) circuit breaker remain in an electrical panel or does it have to be removed?

• Can circuit breakers be installed upside-down, with the breaker "ON" in the down position?

When did circuit breakers replace fuses in homes?

• What is the NEC disconnect requirement for permanently connected appliances rated at not over 300 volt-amperes (watts) or 1/8 horsepower?

• How can I tell the age of a Square D electric panel from the serial number? 

Should I buy a house with a fuse panel/box? 

How dangerous is rust and corrosion inside an electrical panel?

 Are old fuse boxes illegal?

• Does a subpanel require a main breaker by code? 

What is the six breaker throw rule? 

• Is a home inspector allowed to open an electrical panel?

Why are Challenger electrical panels not insurable? 

When did they stop using aluminum wiring in houses?

• Can you splice wires in an electrical panel? 

Are double tapped breakers illegal?

• Does code allow an electrical panel in a storage room? 

Can an electrical panel have more than one main breaker?

How far away do plumbing pipes have to be from an electrical panel?

• Why are there no neutral pigtails at the AFCI and GFCI breakers in the panel?

• What electrical panel locations are prohibited? 

Can an electrical panel be in a bedroom?

• Are Wadsworth electrical panels dangerous? 

How many NM-cables allowed in an NM-connector clamp?

What is the correct size breaker for the tons of my heat pump or air conditioner condenser? 

Where are electrical breaker panels not allowed by code?

How old is a Wadsworth breaker panel?

• How old is a Walker EQ Load Center electrical panel? Is it unsafe? 

Can the total amps of all the breakers in an electrical panel be more than the amperage rating of the panel?

• How old is a Pushmatic electrical panel? Is it safe? 

What is the breaker with a blue test button?

• Can you use an electrical panel as a feed-through raceway for wiring that is not connected it? 

What is a service conductor?

• What is a feeder conductor? 

What are the busbars at electrical panels made of?

• What is a CTL breaker? 

What are the code requirements for an electrical panel cover and door?

• What temperature is too hot for a circuit breaker? 

How do I determine the age of a Gould electrical panel?

• How do I determine the age of a Challenger electrical panel? 

How do I determine the age of a Westinghouse electrical panel?

Can you mount an electrical panel face down?

• Can you mount an electrical panel face up? 

Can an electric panel be mounted over stairs? 

Can an electrical panel be located under stairs?

• Can an electrical panel be located at a stair landing? 

What is a classified circuit breaker?

• What is the difference between specified and classified circuit breakers? 

What is the fireman’s switch emergency disconnect requirement for residential electrical service?

• What is the code minimum height for an electrical panel? 

What is code for relocating an electrical panel?

• What are common problems with split-bus electrical panels?

• Are split-bus electrical panels illegal? 

How do I determine the age of an electrical panel?

• How do I determine the age of a Thomas & Betts electrical panel? 

• What is an electrical subpanel?

• Are Westinghouse electrical panels dangerous? 

• How do I determine the age of a Murray electrical panel?

• How can I keep wasps out of my electrical panel box? 

• Are Murray electrical panels safe? 

• Does a subpanel have to be the same brand as the main panel? 

• How do I determine the age of a Bryant electrical panel? 

• When is an electrical panel overcrowded with too much wiring? 

• How can I tell a main electrical panel from a subpanel? 

• Can service condutors be installed in the same raceway/conduit with feeder or branch circuit conductors? 

What is the difference between specified and classified circuit breakers?

• Can you substitute two 120-volt breakers for a 240-volt breaker in a panel? 

Does code require a whole-house surge protector for houses? 

• Does a whole-house surge protector need a dedicated circuit breaker? 

• What are the requirements for an electrical panel cover (dead front)? 

• Can I use a 240-volt (double-pole) breaker for 120-volt circuits? 

• How many circuit breakers can I add to my electrical panel? 

• How close can an electrical panel be to a toilet? 

• What is an electrical dead front? 

• What are the common problems with an electrical panel dead front? 

• Which Square D electric panels were recalled in 2022? 

• How often should I exercise the circuit breakers in my electrical panel? 

• Where can I get replacement screws for the cover of my electrical panel (dead front)? 

• What is the box marked PowerBlaster in my electrical panel? 

• Do home inspectors turn on circuit breakers?

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