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Darkwood
I see issues all the time with cable burn outs, mainly because I work with alot of heating equipment like elements etc, what I think you may have forgotten here is how heat dissipates from a cable, pushed beyond its thermal limits you get what is known as a runaway effect as temp' will continue to rise well beyond the thermal breakdown point of the insulation.
IMHO I would heed caution about becoming complacent with these values just because you feel you never see any issues, you have to remember exceeding the rated value for long enough will damage the dielectric strength and properties of an insulator, if the temp' does not exceed it for long or too high then it is very likely you will see no visual damage but that's not to say that it hasn't started to breakdown, it can become prone to moisture ingress which inturn would cause the obvious issues expected with that.
Another point would be to also note that a very short momentary current spike like in a fault will not damage the cable as long as trip times are met, exceeding these trip times is when these currents will be expected to damage the insulation hence we have to show a circuit meets them, also inrush currents associated with inductive loads are generally fine too but if one has a high inertia load with a long start-up time then you often need to increase the cable size well beyond the actual running current max value associated with such a load or not only would the cable suffer damage but it acts as a choke on the motor start-up and can lead to damage of the motor as well as dragging the mains voltage down.
Like I expressed earlier, I deal with element connections where high temp' terminations are required and sometimes its down to trial and error as finding out the exposed temperatures of these terminations is somewhat a guess work if you have no prior reference points to actually physically measure from.
IMHO I would heed caution about becoming complacent with these values just because you feel you never see any issues, you have to remember exceeding the rated value for long enough will damage the dielectric strength and properties of an insulator, if the temp' does not exceed it for long or too high then it is very likely you will see no visual damage but that's not to say that it hasn't started to breakdown, it can become prone to moisture ingress which inturn would cause the obvious issues expected with that.
Another point would be to also note that a very short momentary current spike like in a fault will not damage the cable as long as trip times are met, exceeding these trip times is when these currents will be expected to damage the insulation hence we have to show a circuit meets them, also inrush currents associated with inductive loads are generally fine too but if one has a high inertia load with a long start-up time then you often need to increase the cable size well beyond the actual running current max value associated with such a load or not only would the cable suffer damage but it acts as a choke on the motor start-up and can lead to damage of the motor as well as dragging the mains voltage down.
Like I expressed earlier, I deal with element connections where high temp' terminations are required and sometimes its down to trial and error as finding out the exposed temperatures of these terminations is somewhat a guess work if you have no prior reference points to actually physically measure from.
