Reuben's Home Inspection Blog

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What's Wrong With Fuse Panels?

Why are people scared of fuses?  Many people think that fuses are unsafe, but this couldn't be further from the truth.  A properly installed fuse is just as safe as a circuit breaker, but there are many reasons why fused homes can have problems, and I'll discuss a few of the most common problems.

 

To start, how can I say that a properly installed fuse is as safe as a circuit breaker?  A fuse will only handle the amount of amperage that it is rated for.  If a fuse is rated for 15 amps and more than 15 amps passes through the fuse, a thin strip of carefully calibrated metal will vaporize, which opens the circuit (in other words, kills the power).  A fuse will never allow more current to pass through than what it is rated for.  Circuit breakers are designed to trip when too much current passes through for too long a period of time.  Circuit breakers can be reset after they trip, which is a huge advantage over fuses, but they don't add any level of safety.

 

Today, circuit breakers are used in homes instead of fuses.  The main reason is that a circuit breaker can be re-used.  Once a fuse blows, it has to be replaced.  Old electric services will have fuses, and old electric services can have problems.  This is why people get scared of fuses.  A typical 60 amp fuse box might have one 240 volt circuit for an air conditioner or electric range, plus four more fuses for the rest of the wiring in the home.  Compared to the minimum number of circuits required today, this is totally insufficient. 

 

In a new home, a kitchen will typically have one circuit for the dishwasher, one for the disposer, two for the countertop outlets, one for the lights, and another for the microwave and fridge.  This is a minimal installation, and many electricians will also put the fridge on its own circuit, and have another 240 volt circuit for an electric range.  This adds up to nine spaces in an electric panel.  The example I gave for an old 60 amp panel only has six spaces available for the entire house!

 

With today's demand for electricity, old services are usually inadequate.  To make up for this, occupants will often use fuses that are too large for the wires, which will keep fuses from blowing, but also creates a fire hazard.  The photo below shows a wire that is only rated for 15 amps connected to a 30 amp fuse.

 

Unsafe Fuses

 

Many times, people will add several wires on to one fuse, but each fuse is supposed to have one wire.  This is often referred to double tapping, or double lugging.  This is a very common defect for both fuse panels and breaker panels, but the repair is usually quite simple at a breaker panel; not so for an overloaded fuse panel. The diagram below illustrates this.

 

Double Tapping

 

 

A typical service upgrade from a fuse panel to a breaker panel will cost about $1500.00.  The price will continue to go up if new circuits are added to the home.  A good home inspection will identify immediate defects or hazards with a fused electric service, but will not determine whether the service is adequate for the new owners needs.  The bottom line is that there is nothing inherently wrong with fuses, but we do find problems with the wiring in most fused services.

 

Reuben Saltzman, Structure Tech Home Inspections - Email - Minneapolis Home Inspections

Reuben Saltzman, Structure Tech Home Inspections

        

Comment balloon 4 commentsReuben Saltzman • February 12 2009 06:25AM

Comments

Another large problem with an older fuse type system is that the majority of the insurance providers will not cover a home for a new owner with a fuse type system.  Same goes for a home with a knob and tube electrical system.

Nothing will last forever and with an electrical system having an expected life of 40 or so years, we see many that need to be replaced. 

Posted by Scott Patterson, ACI, Home Inspector, Middle TN (Trace Inspections, LLC) over 10 years ago

Reuban,

One of the problems that we're starting to see here with the old fuse blocks is that the bakelite is deteriorating and starting to crack, weakening the system and making a fire more likely.

Also, the propensity of human beings to be creative and use pennies washers and whatever else is at hand was probably a large reason they went out of fashion.

As a technology, they were and are fine.

Posted by Paul Duffau, Caring for People, Educating about Homes (Safe@Home Inspections, LLC in SE Washington) over 10 years ago

Excellent post Reuben,

As you mentioned, the biggest problem with fuse panels has nothing to do with the technology, it is a problem with the occupants. When they grow weary of changing out 15 amp fuses each time they operate the toaster, microwave, blender, and coffee pot at the same time, they solve the problem by installing a larger fuse. While these systems were adequate and considered state of the art by pre world war 2 standards, they are outdated and inadequate for todays consumers. Unless of course your families entertainment still consists of gathering around the radio to listen to the latest episode of Amos & Andy.

Kevin 

Posted by Kevin Welch (American Bulldog Home Inspection Inc.) over 10 years ago

Fuse panels are perfectly fine and have a better chance of blowing than a breaker does tripping.

The only problem is that insurance companies frown on them and they are often undersized due to the amount of circuits, otherwise a properly wired fuse panel is just as safe as any other.

 

Good point.

Posted by Jeff Remas, Inspector Jeff (Advanced Code Group) about 10 years ago

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