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DEADLY WIRING FAULT ; Atten 858D+ Hot Air Rework Station

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saturation:
I didn't think its too big a risk, as the minimum for safety was the chassis grounding and the fuse.  However, if you feel so compelled, you can take a dremel tool and cut grooves into the PCB to separate the mains voltage from the DC voltage.

As example, see the pic I posted of the handpiece PCB: this combines VDC for the fan connection, the temperature feedback sensor and the line voltage VAC for the heating element. 

The 2 large red wires at the bottom are VAC.  Its fed by the grey and clear wires coming from the station, on the right of the picture.  Notice how the DC and AC elements are grouped together and separated, and from the lighting you can see the conductive traces behind it.



I think the separation is adequate, but if the AC did cross over into DC it would burn the components and at worse open circuit the device and at best, sustain a short long enough for the fuse to blow.  So, insure the fuse is well done and your grounding connections good.




--- Quote from: SimonIremonger on August 13, 2011, 08:23:55 am ---I found, indeed, that the casing was not grounded anywhere!  Same problem with paint all over the place.
Also, the mains plug didn't comply with BS1363 (shrouded earth pin!) and contained 13A fuse, highly inappropriate for the very thin bundle of strands in the cable...
I changed cables, scraped off paint all of those spots, and added a ground tab using the transformer's connection to the casing, directly to the earth pin on the inlet.

Initial looking at the circuit board suggests, also, that little attention is paid to isolating low and high voltages anywhere.  Had anybody noticed this?


--- End quote ---

ablacon64:
Man, this is crazy. I'm glad you're fine. I've never seen something like this before, someone may get killed indeed.

SgtRock:
Dear Tasman"

--I am glad to hear you are all right. You may indeed have saved someone's bacon with your warning. First they try to kill you with their fritzy "One Hung Low" DMMs with phoney CAT certifications, and now this. I am constantly reporting substandard knockoff products to eBay (a fat lot they care). Lately eBay  is swamped with phoney Hakko parts that do not fit right and may ruin your good Hakko equipment.

--Apparently a bunch of these mainland companies ship all of their incorrect first attempts and mistakes by beginning solderers out the back door and into the grey channel. Then they claim that was not us, it was one of those dastardly knockoff companies. If somehow they do get enough bad feedback, they just change to another one of their endless stream of identities.

--I had one of these companies tell me they would replace a two dollar defective party if I would change the feedback. I told them, that if they were truly honest they would replace the part and then ask for a change of feedback. I then told them I did not want a new part, but that I would change the feedback if they stopped selling it. Answer came there none.

Best Regards
Clear Ether

saturation:
The 858D is not something you'd run out of the box, but a unique feature of eevblog is finding value in devices and then hacking them to reveal their better potential.  In the case of the 858D, the basic design is sound, but the implementation requires rework.

Chet T16:
I was sure i took my 858 apart when i got it and it was fine, starting to doubt myself now :/

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