Hi,
DZ1 was the diode that I replaced... I've ordered it from Farnell and it should be an SMD zener diode of 2.4 V (http://it.farnell.com/nxp/bzv55-c2v4/diodo-zener-2-4-v-500mw/dp/1097193?Ntt=1097193).
The Ohmmeter probably don't put the diode in conduction state... I can read, in forward and reverse polarization, a value that start from 17kohm and go up until about 18kohm (resistor value).
That value could be the resistance of resistor in paralle with ZD1. But this confirm that there's no shorted component on gate of Power Fet.
With Diode test, I read in forward 0,711V and in reverse 1,627V.
It could be that Farnell gave me the wrong diodes? But no one zener dioda has a working voltage of 1,6V.
ZD1 was not shorted . ZD1 will read 0V if shorted both forward and reverse reading.
ZD1 2.4V might be okay. It depend on Power FET Gate threshold voltage or Vgs. ZD1 was to protect gate of Power FET from over voltage.
Maybe we should check again the resistance of smd resistor 114 and 114X2. I'm not sure if 114X2 were 2 pcs.114 in parallel or equivalent to 55K. If its in parallel, 55k + 110K=165K. Please check resistance of smd resistor that connect between ZD1 and primary filter capacitor. A very high value will cause too low or 1.6V reading on gate of power fet and not able to conduct or start oscillation of inverter circuit.
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