Bob
With the highest respect for you and your profession I must strongly disagree with your findings.
You made this statement;
Excessive heat is often caused by high current through a high resistance contact.
This cannot be a correct statement as when there is an increase in resistance the amperage will drop. Ohm’s law backs this and Ohm’s law is always correct.
The amperage drops but that isn't the point!
The point is that high resistance at a connection in the "fuse box" would cause high heating in the "fuse box", which is the symptom that the original poster observed. That cause would result in high heating even though that high resistance reduces the current in the circuit.
I think what you meant to say here is that arcing due to a lose connection will cause a breaker to increase in heat.
The original poster was talking about a dryer, that operates on 240 Volts. The fact that the amperage drops with higher resistance at a connection in the fuse box is true but doesn't affect the conclusion because the consequece of that high resistance is to cause heating in the fuse box at the location of the high resistance.
In fact, if you do the arithmetic you will find that the heating in the fuse box will increase with greater contact resistance in the fuse box until the resistance at the connection reaches the resistance of the dryer load.
As with a gas welder the acetylene will not do much by itself but add a little oxygen and the heat is a lot greater.
Did we start using more acetylene? No. We only added oxygen to the formula.
This is the same in an arcing event. The ionization of the atmosphere around an arc is what causes the heat not more resistance.
The real fact is that the statement by jwelectric that "Heat means current so the simple answer is something for some reason is drawing to much current." is not supported by the evidence or by any analysis that jwelectric has provided. The "simple answer" is simply wrong!
I believe if we read the original post again we can easily find that the problem is without a doubt something that he did in his installation.
Have problem with fuse box getting very hot.
Here is what I'm working with.
Just bought a new dryer hooked wires up correctly to dryer three prong.
dryer runs to old pushmatic breaker (twin 30 I believe) well the dryer keeps kicking off one side of the breaker on occasion ,the dryer keeps running with no heat.
As can be seen the use of a three wire receptacle makes the installation non compliant. The fact that only half of the overcurrent device is opening says a lot in and of itself. The heating element of a dryer is 240 volts while most dryers have a 120 volt motor therefore the heat will drop out while the motor is still running.
The fact that one overcurrent is tripping and the main overcurrent is heating up leads me to believe that something is wired improperly which is causing a high current draw. If the heat was limited to only one overcurrent device I might agree that a lose connection might be the problem as the arcing would only affect the area of the lose connection and not the entire system.
Now back to my original post;
Heat means current so the simple answer is something for some reason is drawing to much current.
and this is the only thing that will cause the heating in more than one overcurrent device in an improperly installed circuit.
Dryer was hooked up right.
Think problem was running two appliances at same time(dryer and stove both 30amp.) along with everything else,perhaps just pulling too much on that old 60amp.system,I know it should be able to handle it but the house was built in the 40's so I reckon it's a little tired.
Thanks for input fellows.
First if the dryer was on a three wire receptacle it was not hooked up right.
Are both the dryer and stove on the same circuit?