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Electronics => Beginners => Topic started by: mictas on March 10, 2014, 02:36:42 am

Title: Hakko 808 resistor keeps blowing.
Post by: mictas on March 10, 2014, 02:36:42 am
Well I'll try and word this as best as I can, the desoldering gun at my local hacker space has blown for the second time now, one of the other member's walked through the diagnoses and replacement of the offending resistor.

This rather large resistor and is connection to the mains voltage, after the trigger switch. And is not apart of the temp control board, it however is housed with one screw, almost under the motor, its self. The resistor is housed on a single layer PCD board with two other blue companions.

 
Has anyone else had a hakko 808 where this resistor has blown more then once? And if so, is it one of those cases where its just crappy parts or a problem else where, along the line?
Title: Re: Hakko 808 resistor keeps blowing.
Post by: amyk on March 10, 2014, 11:47:25 am
You may want to trace a schematic of the unit to make sure, but from its description it sounds like a current-limiting resistor for a transformerless supply - and if that's the case, the problem could be something pulling too much current through it.
Title: Re: Hakko 808 resistor keeps blowing.
Post by: mictas on March 11, 2014, 07:12:28 am
Quote from: amyk on March 10, 2014, 11:47:25 am
You may want to trace a schematic of the unit to make sure, but from its description it sounds like a current-limiting resistor for a transformerless supply - and if that's the case, the problem could be something pulling too much current through it.

Okay, reading this, I really should get a third party to also take a poke at this.

Thanks for that, I'll keep it in mind the next time we all meet up.
Title: Re: Hakko 808 resistor keeps blowing.
Post by: granz on March 11, 2014, 02:13:40 pm
Be sure that you have the right heater element.  There is apparently a 110V version and a 220V version.  If you have the 110V version and you are running it on 220V you could be drawing way too much current.
Title: Re: Hakko 808 resistor keeps blowing.
Post by: mictas on March 11, 2014, 09:45:15 pm
Quote from: granz on March 11, 2014, 02:13:40 pm
Be sure that you have the right heater element.  There is apparently a 110V version and a 220V version.  If you have the 110V version and you are running it on 220V you could be drawing way too much current.

Well I do not know if the element was replaced, but this is a 220v Australian model and not the US version, I'll have to ask the owner to see what was fixed last time.

Thanks.