Author Topic: Secret origin of the Hakko 888 name?  (Read 2007 times)

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Offline KL27xTopic starter

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Secret origin of the Hakko 888 name?
« on: June 24, 2017, 10:07:47 am »
I just bought some spare 888D soldering stations, (the lure of the recurring Fry's sale) and having read all about the latest and greatest irons in these threads, I wonder if I should have not just bought an FX951 or even fooled around with a (gasp) Bakon950D 75W iron (which is apparently the latest rage in Russia, if you go by the youtube videos, lol). Did I just lock myself into an inferior iron for the next 5 decades? So I decided to see if the Hakko 888 lives up to its power rating of 70W that is printed on the bottom.

The voltage is stated to be 26V.

My true RMS fluke is... somewhere. So I put my scope to the transformer 26V secondary to see what was happening.  In fact, the voltage was very stable, even when the heater was cold (which makes the resistance only 3.2ish ohms). It started out at 90.x V pk to pk. And after perhaps the transformer warmed up a little, it settled to... 88.8V. I expected when the heater was on that the voltage would sag. But this voltage remained completely stable whether the heater was on or off!*

Pk to pk voltage of 88.8 x0.5/1.7 =26.12V rms. Rounded down for measurement error of my scope, it is hitting the mark.

So then I set about measuring the temp of the heater at temp. I figure the average soldering temp is about 350C. So I heated up the iron to 360C for good measure, unplugged it, and I immediately got the DMM probes onto it as fast as humanly possible. And I got... 8.8 ohms.

26V squared / 8.8 ohms = 77W. It looks to me that Hakko is not overstating the specs, at all.

The Bakon runs at 19V. I am not sure what the resistance of the heater is, AT TEMP, but it is said to be around 2 ohms, cold. If we were to extrapolate, let's just say it might be around 2 x 8.8/3.2 = 5.5 ohms ... for a nominal 65.6W. This isn't taking into account the pauses to read the temp sensor, either, which appears to be fairly significant. Probably something like 5% of the duty cycle.

I found this vid, and I am fairly satisfied with my decision.
https://youtu.be/fq439J4ZbrY?t=125
Love that warm up speed on the display. Not so great on the actual melting of solder, though. This is actually pretty close to the same speed as 888, which has higher thermal mass tip. And a much better stand. :)

*I haven't looked too hard at the pcb, and I don't know if there is a public schematic. But there is a large power resistor at the top of the board. I am guessing it might be a dummy load for keeping the transformer output so stable. I might clip this and see what happens.... A little faster cold start time and less power consumption, perhaps? The triac is rated for 600 V, so the longevity of the heater would be the only concern, I think. Well, I suppose I should check all the caps in case they're cutting it close. I'm fairly impressed at the beefiness of the transformer, though. From a cold start it is pumping around 8 amps without any sweat, although I admit I missed the first 5 seconds, while fiddling with my scope voltage scaling and switching from DC to AC... noob mistake. :)
« Last Edit: June 24, 2017, 10:50:16 am by KL27x »
 

Offline stj

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Re: Secret origin of the Hakko 888 name?
« Reply #1 on: June 24, 2017, 12:08:21 pm »
the 951 is an old design, i suspect the newer stuff like the bakon and others have better software / faster cpu's

but generally, T12 tips rule if your spending under $100 and probably under $200 (how much is a jbc?)
 

Offline KL27xTopic starter

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Re: Secret origin of the Hakko 888 name?
« Reply #2 on: June 24, 2017, 12:34:49 pm »
I dont think it takes modern micros running at 40MHz to read an adc and toggle a pin. The adc reading is the slowest part by thousand fold.

I think the vid segment i linked prolly gives the Bakon short shrift, though. I bet the switching supply cant deliver the goods, over 6 amps, when the tip is cold.  I am sure when it is warmed up, it performs very well. But i am pretty sure a 951 is in another league. What does it run at? 24V? 26V? Even if we calculate at 24V, using the same tips as the Baconator, that is 60% more power.

One thing that concerns me re bakon is the lag between 250c on the display and the multing of the solder. It was close to 15 seconds. I know the sensor heater lag isnt that far off even on a counterfeit t12. I can only imagine the firmware is purposely showing false readings to make it look faster. I had an Xtronic that did that. When a hakko shows read temp of 250c, it will melt solder, period.
« Last Edit: June 24, 2017, 12:39:25 pm by KL27x »
 

Offline stj

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Re: Secret origin of the Hakko 888 name?
« Reply #3 on: June 24, 2017, 01:01:46 pm »
it probably wasnt calibrated - ie it may not have been that hot.

calibration instructions come with it, but afaik none of the cheap stations are calibrated.
and in the case of T12 stuff it includes the 951 because there is a noticable difference even between original tips.

the replacement for the T12 has a barcode on the body that is read inside the handpiece as you insert the tip - this sets a specific calibration offset for the tip.
 

Offline KL27xTopic starter

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Re: Secret origin of the Hakko 888 name?
« Reply #4 on: June 24, 2017, 07:43:23 pm »
Perhaps he uses lead free solder, too. That would be reasonable performance. It takes a cold tip quite awhile to get fully to temp, even if it is a cartridge, apparently. Any rate, it looks like the PID isn't particularly fancy on the bakon. Not that I would expect Hakko 951 to necessarily be any different, other than the increased power. I shall probably end up buying one just to see how it performs. Worse ways to spend 30.00.
« Last Edit: June 24, 2017, 08:05:56 pm by KL27x »
 


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