Small AC motors and Inverters
Disappointed that my ancient Mod Sine Wave inverter (140W cont, 200W surge) shuts down with a 120W coffee grinder. Works ok with the 400W (cont) MSW inverter built-into the truck, though a little ...
Forum Discussion
the idea is too NOT run at max wire capacity on a continuous load
the idea of 20% higher fuse "than rated load" not rated wire
never fuse higher than what the wire can safely carry/rated
example the rated load is 40amps, you fuse at 50 amps, this prevents the fuse being over heated from a long load time at say 39-40 amps
but the wire must be able to carry more than 50amps
you want the fuse too blow not for the wire to overheat
terms were being quoted, but out of context from their intended context/use
its good to understand what people are telling you..
but when making decisions, based on charts, you have to know and understand the context of the chart and its intended use,
something that may define maximums.. is not necessarily stating use standards or safety protocol..only what that wire might carry for 5 minutes before becoming dangerously hot
wire use depends load carrying, voltage drop.. well somethings like a heating coil are not harmed by voltage drop, while motors will try to draw more amps and are damaged by heat, caused by the use of more amps, which of course create more voltage drop
voltage drop is a concern of "what the load can tolerate",
a motor using 20 amps can be wired using 12ga wire, but if the run from the breaker center to the motor is 200ft , the voltage drop at the motor "under load" might be too high, so the use of 10ga is advised, the circuit breaker would be 25amps
the motor can use full power and not overload the breaker, the wire is rated for 30a, the breaker will trip before the wire can overheat should the motor fail
SORRY..i don't like to give long lectures
although it sometimes happens
i never had the desire to be a teacher
i don't have the Patience for it
your 100amp Fuse will be find, i still think 2ga is the better choice
but you are beginning to understand. your still thinking in minutes
reverse the process, what if your unit was a combo inverter charger.. plug in 82 amps charging load for 4hrs and see what that wizbang calculator suggests..
the idea of 20% higher fuse "than rated load" not rated wire
never fuse higher than what the wire can safely carry/rated
example the rated load is 40amps, you fuse at 50 amps, this prevents the fuse being over heated from a long load time at say 39-40 amps
but the wire must be able to carry more than 50amps
you want the fuse too blow not for the wire to overheat
terms were being quoted, but out of context from their intended context/use
its good to understand what people are telling you..
but when making decisions, based on charts, you have to know and understand the context of the chart and its intended use,
something that may define maximums.. is not necessarily stating use standards or safety protocol..only what that wire might carry for 5 minutes before becoming dangerously hot
wire use depends load carrying, voltage drop.. well somethings like a heating coil are not harmed by voltage drop, while motors will try to draw more amps and are damaged by heat, caused by the use of more amps, which of course create more voltage drop
voltage drop is a concern of "what the load can tolerate",
a motor using 20 amps can be wired using 12ga wire, but if the run from the breaker center to the motor is 200ft , the voltage drop at the motor "under load" might be too high, so the use of 10ga is advised, the circuit breaker would be 25amps
the motor can use full power and not overload the breaker, the wire is rated for 30a, the breaker will trip before the wire can overheat should the motor fail
SORRY..i don't like to give long lectures
although it sometimes happens
i never had the desire to be a teacher
i don't have the Patience for it
your 100amp Fuse will be find, i still think 2ga is the better choice
but you are beginning to understand. your still thinking in minutes
reverse the process, what if your unit was a combo inverter charger.. plug in 82 amps charging load for 4hrs and see what that wizbang calculator suggests..
