Speaking of flames, Are the thermal fuses of any help in such case?ruffrecords said:The principle function of the fuse is to stop the device bursting into flames when a fault occurs.
warpie said:1Amp?? Is it not a bit too high?
My calculations are based on this and this. I found more info online and they all pretty much suggest the formula I posted.
Fuse rating has always been a mystery for me…
Speaking of flames, Are the thermal fuses of any help in such case?ruffrecords said:The principle function of the fuse is to stop the device bursting into flames when a fault occurs.
There are many factors involved. As mentioned elsewhere there is an inrush current at turn-on due to the magnetizing of the core. The inrush current depends on the timing. Counter-intuitively, it is maximum when turn-on coincides with zero-crossing. And the inrush current due to charging the capacitors depends on the actual value of these capacitors, not on the steady-state current. For a given rated current, one designer may decide to put oversec'd capacitors, which will result in a larger inrush.warpie said:Say that I use a 50VA toroidal transformer (efficiency>93%). Is it correct to assume that I need a 315mA fuse for 230VAC?
(50VA/ 230) X 1.5 = 326mA
thanks
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