Fuses to Breakers...

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Rock Crusher

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I am switching an old fuse box to a breaker panel. Anything special I need to consider beside load calculations and panel sizing?
They dont want a complete rewire, which is the only way I've ever done it. The house is currently knob and tube, with a 100A service.
Thank you in advance.
 
Be ready for some interesting "follow-up. :)
Once you replace their 30 amp plug fuses with properly sized breakers and that one kitchen circuit starts tripping it will be "all your fault"
 
I thought of that, among other issues, and was going to tell them that. I realize, and I'm sure the customer does not, that there will need to be certain updates that wil be required. Some for safety reasons, others just because it's smart. They are a couple of tight wads, so minimum requirments will definately be followed here.
I will not do anything just because a customer wants me to or if it's unsafe. So I might end up not even doing it. I just wanted some input from others as to what I should consider so I don't miss anything.
Thanks for the input:)
 
augie47 said:
Be ready for some interesting "follow-up. :)
Once you replace their 30 amp plug fuses with properly sized breakers and that one kitchen circuit starts tripping it will be "all your fault"
Click to expand...
:lol:
And then they want a larger breaker to stop the tripping..:blink:
 
Rock Crusher said:
I thought of that, among other issues, and was going to tell them that. I realize, and I'm sure the customer does not, that there will need to be certain updates that wil be required. Some for safety reasons, others just because it's smart. They are a couple of tight wads, so minimum requirments will definately be followed here.
I will not do anything just because a customer wants me to or if it's unsafe. So I might end up not even doing it. I just wanted some input from others as to what I should consider so I don't miss anything.
Thanks for the input:)
Click to expand...
Just bring some 14 and 12 solid because the wires are usually too short..:)
 
When doing such a job I have always planned for the fact that if certain things do not exist they will have to be added/modified etc.

Make sure you have at least two 20 amp circuits to kitchen receptacles, and if possible no other load on those circuits. There is good reason this is minimum requirements for new construction.

Make sure you have separate circuit to laundry.

It is nice to have separate circuit to bath receptacle just like you probably would if new construction, but at very least make sure it is not on a lighting circuit with lots of other outlets or even 15 amp circuit - hair dryers take all the capacity of a 15 amp circuit usually, so there will be problems if much else is on with bath outlet.

Make sure you have any other circuit capacity hogging appliances separated from other loads that will not play well together on same circuit.

Follow that advice and often you will get away with little or no trouble if the remaining general lighting is only on a couple circuits.
 
One of the things you need to watch out for in a situation like this is what you hook up to opposite legs. K+T often got fed at different places and neutrals might be shared or 3-way switches fed from two different circuits since many K+T installations were done when houses had a two wire service with just one leg. Unless you know that a circuit is designated or make a schedule of circuits as they're connected now, it might be safest to connect the K+T circuits to the same phase or you run the risk of blowing things up.
 
Another thing about 3-ways

Another thing about 3-ways

Old three ways often switch the hot and neutral. If you replace the old 3-way switches (which were break-make) with modern 3-way switches (which often are make-break) you will produce a short-circuit during each switching operation.
 
fmtjfw said:
Old three ways often switch the hot and neutral. If you replace the old 3-way switches (which were break-make) with modern 3-way switches (which often are make-break) you will produce a short-circuit during each switching operation.
Click to expand...

What kind of three way switches do you use? I have not had one apart in a long time and not saying "make-break" doesn't exist, but have never noticed one that was designed that can make the new position before breaking the old position. They are simple double throw device that works just like how you typically would draw a SPDT switch. Most of the "make-break" designs I have ever seen are involved in industrial push buttons and selectors and are generally more of a special contact block vs the standard double throw or have different length actuating mechanism so they operate differently than what a standard contact does.
 
limited experience

limited experience

kwired said:
What kind of three way switches do you use? I have not had one apart in a long time and not saying "make-break" doesn't exist, but have never noticed one that was designed that can make the new position before breaking the old position. They are simple double throw device that works just like how you typically would draw a SPDT switch. Most of the "make-break" designs I have ever seen are involved in industrial push buttons and selectors and are generally more of a special contact block vs the standard double throw or have different length actuating mechanism so they operate differently than what a standard contact does.
Click to expand...

In my limited experience with the old 3-way switching, I found that modern 3-way switches shorted out the two legs as part of their operation. I've not made a study of it. With properly wired travellers it doesn't make any difference. I may do some tests later when I'm less busy. You can make a 3-way work either make-break or break-make depending on the width of the wiper arm contact end and fixed contact width or position.
 
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