Wednesday, November 13, 2024

Breakers or fuses

 

An assortment of load limiting devices from my personal stash

 

Breakers or fuses?

A fuse box has fuses, a breaker panel has breakers, and the names are no more interchangeable than calling all coffee Old Judge or Starbucks.

Sadly electrical manufacturers have made the choice for us by discontinuing fused load centers.  Personally I am pro fuse as fused load centers last and last without much upkeep.  When a fuse blows there is no doubt it blew.

A fuse box recently removed by myself after 100 years of service

 

Breakers are nice in that you can just turn a blown one off and back on again, but they lack the financial incentive to figure out why they blew.  

A reasonably well installed box that I had to inspect recently

 

The dark side of breaker panels is many have been recalled for failing then burning down the building.  Breakers can and will catch fire, typically they smolder, but can ignite–I have had this happen in my previous home and coincidentally it had one of those recalled panels.  

A burnt 100 amp main breaker I replaced over the summer

 

Breakers will fail and trip for no reason causing you to spend on an electrician to diagnose where the problem is when there isn’t one.

There are some neat and often code enforced breakers out there that do truly add levels of safety such as:

Arc fault Circuit Interrupters

These are highly sensitive breakers that detect loose wiring connections (faults) and cause them to trip.  All circuits loosen over time–more on how later–so these add a layer of protection to your home as it is the single most expensive thing you own.

Ground Fault Circuit Interrupter–I bet many of you wondered what GFCI meant on outlets–breakers

Similar to an arc fault but different function, these are more used in wet locations or in instances where electricity and water meet like the pump in a pool, spa, or jetted tub.  Water is an excellent conductor of electricity so say you drop an electric razor in the tub while your significant other is taking a relaxing bubble bath with their rubber duckie or warships, the GFCI will trip almost instantly.  A normal outlet will cause your significant other to get quite a charge they didn’t expect–hence why any outlet within six feet of a sink, tub, toilet, or outside anywhere, is required to have either this breaker or a GFCI outlet.  These breakers are mandatory on pools, well pumps, spas, for the obvious reason that the pump is moving water and overtime water leaks.

Now back with Arc Fault breakers I mentioned that circuits loosen, but how?  Anytime you draw power through a wire it creates heat, sometimes you will notice a wire is warm when using a long extension cord.  That is because no conductor is perfect and they all have resistance over their length–extension cords could almost be their own article.  Now if you stick a voltmeter in any socket of your home you will get either 110v or 220v–give or take depending on your supplied voltage–and that is because there is no real load, but with a special set of adapters you can read both the load being drawn and the voltage present.  The higher the load and smaller the wire the more the voltage drops causing the load to increase and the more load the more heat made.  Light circuits are typically run in 14 gauge wire, normal outlets in 12 ga wire, 14 maxes out at fifteen amp load vs 12 maxing at twenty amp load (chart here).  As the wire heats and cools it changes size very slightly and over time it causes the screws that secure it to fixtures to loosen or you could say it causes the wire to deform and become loose–same for wire nuts traditionally used to make connections where there is no fixture but either a wire splits to multiple places or one wire is tagged to another to keep going–this is why it is against code to cover any junction box.

If you want to stay safe and protect your investment you should have a qualified electrician inspect and retighten your wiring about every ten years–I’d go five if you are unfortunate to have aluminum wiring.  Loose wires are why arc fault breakers exist but that is because people forget to have the electrical system serviced regularly.  Can you do this yourself?  Yes and no.  If you are not familiar with what a bus bar is and what it does you should probably not go near the inside of an electrical distribution box be it fuses or breakers.  If you have to look up how to install an outlet again don’t plan to tighten your own.  There are special torque tools to ensure the terminals are as tight as they should be without breaking them and most people can’t justify the expense for something they do every five to ten years.  Oh and for reference you can turn off the main breaker for any work in the panel but you CANNOT turn off the power coming into the main breaker and those lugs must be tightened as well.  Those main lugs take a very expensive set of sockets to tighten down and even to an electrician those tools are expensive!  (I should know I have the sets myself)

In the end both breakers and fuses do the same job, the big deals are to have them serviced regularly.  Keep inexperienced fingers out of the panels.  Keep regular tools out of the panels.  If something does start going wrong call a pro and save your home or business from catastrophe and with proper inspection reports you may just get a discount on your owner’s insurance.

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