Hakko FX-888 220V -> 110V Mod - Page 1
Forum section: electronics / general

author: embcreations
author_rank: Newbie
timestamp: November 26, 2013, 04:18:27 am
content: While on a few week stay in Shenzhen, I needed to pick up some tools. I bought a Hakko FX-888 at a shop in SEG Market. It was an impulse buy, and while I thought it would be easy to bring it home to the US with me to use in my lab, I didn't realize before purchasing it would need some modification to work at 110V. The iron was purchased at a good price I thought, 400 RMB, about $66 USD, after a little haggling from my Mandarin-speaking wife. The shop I purchased from is easy to find, it's on one of the outer edges on the 2nd floor of SEG Market. It's named "Elvis", with a big sign on the wall so you can see it from across the floor. I also purchased a DS-1052E scope there, for 1600 RMB (~$263 USD), again after a little haggling. The shop owner was nice, and was able to help me pick out some Hakko tips from a catalog with my few word Mandarin vocabulary when I was there without my wife.The iron does seem to be a fake, not a genuine Hakko product, though it almost convinced me with the packaging and manual. I'm happy with the quality so far.The EEVBlog forums seems to be the place to discuss this iron and modifications, but the posts I read seemed focused on the 110V to 220V mod, while I need the opposite. I have zero experience with transformers, so I read all the posts here, and searched around for some more info. I found a post elsewhere talking about an ebay purchase of a 220V iron modded to 110V that was botched. That gave me some clues that it was possible to mod my iron without needed a new transformer.http://www.diyaudio.com/forums/blogs/rjm/1026-hakko-fx-888-ebay-unhappiness.htmlLike the post above, my fuse board was soldered in backwards. I'm not sure if this a mistake or was was done on purpose by the factory, but I had no issues using the iron with 220V while in China.To modify my iron, I purchased a 2A fuse and removable fuse holder, and a grounded universal outlet adapter to US plug. If I return to Shenzhen, I'll want to bring this iron with me, so that's why I didn't swap out the power cable.I desoldered the fuse board from the transformer, which was quite difficult with the little 15W spare iron I had, and soldered it back on the right way. After replacing the 630mA fuse with the fuse holder and 2A fuse, I connected the hot power wire from the switch to the 110V/120V/240V pad, and was measuring 29VAC on the other side of the transformer. I was expecting 24V, so this seemed a little high, but I plugged in the iron and saw between 25V-29V while heating the iron up, and nothing blew up.Should I be concerned about the 25-29VAC output from the transformer? I'll continue using the iron and post back with any problems if I have them.

author: amyk
author_rank: Super Contributor
timestamp: November 26, 2013, 10:20:19 am
content: Quote from: mojo-chan on November 26, 2013, 10:06:02 amAs good as every other 936/888 clone out there...?I wouldn't worry about a few volts higher; the heater will probably handle it fine and you might even get faster heatup (how much power does it draw?)

author: BravoV
author_rank: Super Contributor
timestamp: November 26, 2013, 10:24:14 am
content: The secret sauce of good performance is the genuine tip + genuine heater (with built in sensor) + a proper driver & sensing circuit at the solder station base.Fakes just don't have this luxury even its successfully modded to adapt to local mains voltage, to get the same performance as genuine Hakko "if" this is the OP's mission, then its still a long-long way to go.

author: embcreations
author_rank: Newbie
timestamp: November 26, 2013, 05:22:24 pm
content: Thanks for the feedback.My goal right now is to have a working soldering iron. I understand a genuine Hakko Iron will have better performance, and I'll upgrade to a model from an authorized distributor if I need that performance in the future.I unfortunately don't have a power meter so I can't measure how much power it's drawing.

author: creyc
author_rank: Regular Contributor
timestamp: November 26, 2013, 06:39:39 pm
content: Will the tip temperature be way off?Without seeing a schematic of the temperature sensing circuit I guess theoretically it could still regulate the heater regardless of voltage, but I wouldn't put much trust in the temperature on the dial until you can test it with a temp probe..

author: amyk
author_rank: Super Contributor
timestamp: November 27, 2013, 07:45:22 am
content: The original 936 and all its clones used a zener-based reference, I don't think this one is going to be any different. With a more powerful heater you may get more oscillation around it but the setpoint won't change with the supply voltage.