High frequency rating of power fuses
High frequency rating of power fuses
(OP)
Does anybody have any information or suggestions on the high frequency ratings of fault current limiting fuses? I have a 1200V application where we are using standard 50Hz fuses at fequency of 1050Hz (ripple control frequency injection for hot water heater control). Points that my gut feel says may be important are that:
1] the applied voltage and the self-inductance of the load circuit determine the rate of change of current,
2] the I2t is determined by the rate of change of current and the time it is applied,
3] the rate of change of applied voltage is higher with higher frequencies (what about tranient effects?)
Any ideas?
Bung
1] the applied voltage and the self-inductance of the load circuit determine the rate of change of current,
2] the I2t is determined by the rate of change of current and the time it is applied,
3] the rate of change of applied voltage is higher with higher frequencies (what about tranient effects?)
Any ideas?
Bung






RE: High frequency rating of power fuses
1)I figure the peak let through will be much higher because of the rate of rise of the fault current.
2)The melting currents may be lower because of the skin effect at the higher frequency.
I would suggest you contact a manufacturer on the issue.
RE: High frequency rating of power fuses
I have asked the fuse manufacturer, but often the manufacturer's view of life isn't the same as the user's view...
Bung