I am working on a ASTEC 150 watt AC/DC SMPS power supply model:LPQ154,CSA File No:LR84459,year:May 1995:
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I found the outside 3 amp long fuse burnt,F1=5 amp small (on the main board) burnt,along with Q1=IRF840 and Q2=IRF840 in the troubleshooting process I assumed Z4= was shorted but it wasn't and I broke it in two. Does anyone have the value for Z4=Zener diode?,the # I got off it was something like "2C2" which if correct is 2.2v but when I put one in along with new Q1 &Q2 the unit's secondary voltages try to climb but the 100 watt light bulb I placed in series with the line voltage is limiting the current and thus preventing the same failure of parts.
Sidney E-mail:sidneybek(at)yahoo.com Dartmouth,Nova scotia Canada