so did i understand right, the breakers don't trip at a loose wirenut ect fault, but only on "real" short circuit faults?
thanks for your input
If you are interested, that's a graphic trip diagram for european/german breakers: http://www.anghuber.de/leitungsschutz/pic3.jpg
time in seconds and minutes on the vertical, current multiplier on the horizontal
B, C and D show the trip characteristics. B Breakers are usual for normal homes and pretty fast. C and D (and K, not shown) are slower for bigger machines with high startup currents). As shown, above 5 seconds they all act the same.
You see that the 16A breaker will sure trip at a 80A spike (16A * 5).
The bottom text diagram shows Thermal tripping on the left and shortcirc tripping on the right.
For the B characteristics, the Breaker needs to stay on for > 1 hour at 1.13*Current, and needs to trip in <1h at 1.45*current.
Short circuit trip is given at 5*current faster than 0.1 secs.
at 3*current slower than 0.1 sec.
[This message has been edited by :andy: (edited 10-10-2004).]