EEVblog Electronics Community Forum

EEVblog => EEVblog Specific => Topic started by: nanotech on September 11, 2013, 03:28:41 pm

Title: hakko 850
Post by: nanotech on September 11, 2013, 03:28:41 pm
hi all im new so please be gentle   :-[
i have a problem and i hope you can help.i have a hakko 850 which has the motor running constantly when the power switch is off , also when i switch the machine on the heating element goes on full blast and then i have to switch off straight away to avoid it burning out . i love these machines and they go on forever and i would hate to throw this one away unless i can fix it ,if you could let me know what could be the problem and how i could trace it i would be very grateful  thanks in advance
Title: Re: hakko 850
Post by: nanofrog on September 11, 2013, 06:42:39 pm
Hope this helps.
Title: Re: hakko 850
Post by: nanotech on September 14, 2013, 09:38:17 am
hi thanks for the schematic but i havent got a clue where to start  |O
can somebody please enlighten me as to which components i should check first and which ones i should be replacing  :-+
Title: Re: hakko 850
Post by: SeanB on September 14, 2013, 09:55:43 am
With the fan running all the time I would guess checking C7, C10 and the 555 IC, along with the triac TH2, and D3, C9, Q1, Q2 and Q3. Heater on all the time check TH1 for a short, and if it is fine then the UPC1701 and C2, PUT1 and the wiring to the pots and the pots themselves if they are open circuit.