Password reset procedure for Hakko FX-888D

[matt_triskit]

I found this procedure and printed it out about a year ago and made a guess about what was inside the "dongle". Now it seems to have disappeared from Google search results, so I am reposting it here.

I was able to use this procedure to unlock a station where a former employee had set the password and then left the company.

First of all, the "dongle" mentioned in the original procedure seems to just be a resistor emulating the temperature sensor, but for simplicity I will just refer to it as a dongle.

• Turn off the station.
• Unplug the iron from the station.
• While holding down the ENTER button, turn on the station.
• "S-E" should be displayed. Release the ENTER button.
• Plug in the dongle. First the set temperature is displayed, then the sensor temperature is displayed (based on the resistor used to emulate it).
• After the sensor temperature is displayed, unplug the dongle.
• "S-E" should be displayed.
• Plug in the dongle.
• First the set temperature is displayed, then the sensor temperature, then "rSt".
• Turn off the station.

If "rSt" is not displayed, repeat...

[MathWizard]

Why is there any PW on a soldering iron ? So kids can't turn it on ? Or coworkers can't gunk up people's irons ?

[Whales]

Thankyou mat triskt.  This will be invaluable to avoid perfectly good stations going to waste.

This might have been a requested feature from a client at some point (possibly even from a product prior to the 888).  Somewhere, somehow a lockout was probably wanted for some safety compliance.  Might even be something obscure like preventing people from using unsolicited alloys on the tip of a special jobstation in the aerospace industry, lest bad alloy remnants mix into future joints and cause leeching/fatigue/etc.

[matt_triskit]

I think in this case the reason for the password was to avoid accidentally messing up the calibration. On the FX-888D it is WAY too easy to mess up the calibration—press and hold the up arrow and you think you're adjusting the temperature, but you're actually changing the calibration. There are two levels of password protection, IIRC: one just protects the cal, the other completely locks the iron to a fixed temperature.

In theory, the password feature is a good idea if you're a supervisor who doesn't trust your technicians to use the correct temperature, but if the part you're soldering is that temperature-sensitive, reflow is probably the only correct way to do it anyway.

[audiotubes]

I think in this case the reason for the password was to avoid accidentally messing up the calibration. On the FX-888D it is WAY too easy to mess up the calibration—press and hold the up arrow and you think you're adjusting the temperature, but you're actually changing the calibration. There are two levels of password protection, IIRC: one just protects the cal, the other completely locks the iron to a fixed temperature.

That's interesting. How do you check if you screwed it up? Most el-cheapo thermocouples I have seen don't go higher than 250C or so.

[matt_triskit]

Well, on the FX-888D it’s just a one-point calibration so if it’s wrong at a low temp it’ll be wrong at a high temp too. But you can also do a factory reset to be on the safe side.

[wraper]

Why is there any PW on a soldering iron ? So kids can't turn it on ? Or coworkers can't gunk up people's irons ?

Because on production lines you want consistent process, not workers fiddling with settings to their preference.