QUOTE (lilDetails @ May 30 2009, 12:01 AM) [*]690527[/*]
QUOTE (Jarrett @ May 29 2009, 01:29 AM) [*]690195[/*]
I didnt read all the post, but due to Ohms law Voltage=(Ampere)(Resistance)
V=I*R
If the heat gun requires more current than can be adequately supplied the smaller gauge wire will increase in temperature (Ex try grounding just a small wire from your battery positve to your car frame or batter negative, it will instantly melt!) Ive accidentaly done this with a wrench
Scarry!
Anyway, so if the temperature of the wire increases then the resistance increases... this is due to the temperature coefficient of the wire (what ever it is for your wire).
Now, that wall recepticale will only give 120 Volts and assuming no more then 15 or 20 amps (depending on circuit breaker, those are common).
So is Resistance is going up b/c V=IR and V is constant... that means I=V/R... so more current is required, thus blowing the fuse when the current drawn exceedes the circuit breakers max amperage. (like I said usually 15 or 20 amps for 120V wall outlets).
Note if the circuit breaker was not there the current would increase to a level that would eventually melt the wire, thus causing an arc (spark), thus probably causing a fire inside of a wall!
But on another note most wall receptacles are connected to many other receptacles and other devices ex lights, fans, etc... so the heat gun is probably not the only device drawing current.
but what do I know, I only have an electrical degree
... actually i do haha.
V=I*R
If the heat gun requires more current than can be adequately supplied the smaller gauge wire will increase in temperature (Ex try grounding just a small wire from your battery positve to your car frame or batter negative, it will instantly melt!) Ive accidentaly done this with a wrench
Scarry!Anyway, so if the temperature of the wire increases then the resistance increases... this is due to the temperature coefficient of the wire (what ever it is for your wire).
Now, that wall recepticale will only give 120 Volts and assuming no more then 15 or 20 amps (depending on circuit breaker, those are common).
So is Resistance is going up b/c V=IR and V is constant... that means I=V/R... so more current is required, thus blowing the fuse when the current drawn exceedes the circuit breakers max amperage. (like I said usually 15 or 20 amps for 120V wall outlets).
Note if the circuit breaker was not there the current would increase to a level that would eventually melt the wire, thus causing an arc (spark), thus probably causing a fire inside of a wall!
But on another note most wall receptacles are connected to many other receptacles and other devices ex lights, fans, etc... so the heat gun is probably not the only device drawing current.
but what do I know, I only have an electrical degree
... actually i do haha.In your own statement current is voltage DIVIDED by resistance and the wire resistance increases as the wire heats up from power draw. So the power draw will DECREASE as the current is going to decrease from the higher resistance.....
Higher resistance is going to pull less current!
and what do I know as I also have a Electronics degree....
Yes I see what you are saying, if we take the limit of R as approaching infinity current would become zero. But I dont think I explained what I was trying to say completely. That is in the wire, the wire doesnt really need any current (the current it uses disipates as heat).
Ex if you have a power supply that can only supply 1 ampere and a circuit that needs 5 ampere to operate then you will probably keep blowing the fuse/circuit breaker on the power supply. Thus the heat gun still needs a certain current to operate so as the wire's resistance increases the heat gun cannot get the needed amperage to operate. Thus possibly melting/deforming the wire.
I think I see what I didnt explain correctly. I meant the current needed for the heat gun overcomes the current that the wire can handle safely, thus the wire acts as a circuit breaker and can melt/deform... Does that make more sense??? I hope so, sorry.
Anyway, my whole point earlier is that I think the circuit is blowing due to having other devices on the same 15 or 20 Ampere circuit breaker... the lights, fans, etc.
