Re: 18VDC PSU has dropped to 10v - ZD-915 desoldering station
Ok as it is now it works after maybe 10-20 seconds of flashing error/heat and beeping at about 4Hz, seems to be overloading, shutting off, coming back on. Doesn't do it with the gun unplugged. It's making a high pitched noise for a while too, the psu is still not happy. Annoyingly I reassembled it. Do you know the part numbers of the chips and mosfets? If theyre cheap enough I might just shotgun the lot and be done with it. All caps had low esr....
phreak97
Member
Last Activity: 08-02-2019, 06:39 AM
Joined: 10-19-2017
Location: South Australia
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Re: 18VDC PSU has dropped to 10v - ZD-915 desoldering station
These are just built poorly....Leave a comment:
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Re: 18VDC PSU has dropped to 10v - ZD-915 desoldering station
Stronger yes but more susceptible to cracking with repeated expansion and contraction....Leave a comment:
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Re: 18VDC PSU has dropped to 10v - ZD-915 desoldering station
Probably not a terrible idea...Leave a comment:
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Re: 18VDC PSU has dropped to 10v - ZD-915 desoldering station
Usually an hour or so at a time, sometimes more, sometimes less.
The solder failed because it's badly soldered in the first place...Leave a comment:
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Re: 18VDC PSU has dropped to 10v - ZD-915 desoldering station
Yeah maybe I'll reflow that too then just see how it goes...Leave a comment:
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Re: 18VDC PSU has dropped to 10v - ZD-915 desoldering station
Ok it’s working now but i’m not super confident that it’s actually fixed. I reflowed the vref chip, pwm chip, and mosfets, then put it back onto the heat sink with some breakout wires to put a load on it. It worked fine straight away. I did hear a buzzing sound from the transformer for a short while though which was odd..Leave a comment:
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Re: 18VDC PSU has dropped to 10v - ZD-915 desoldering station
Thanks! I'll do those things and post back. The fan box has two resistors inside and the fan is labelled 24v...Leave a comment:
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18VDC PSU has dropped to 10v - ZD-915 desoldering station
My ZD915 desoldering station lost fan speed, pump speed, and peak heating ability yeaterday. Today I did some investigation and discovered the 18v psu is only outputting 10v. Now, I know the basic idea of how a switching pau works but not well enough to quickly diagnose the faulty component. I know the transistor controls the pwm via the opto-isolator, and how the pwm drives the transformer, but I haven't the faintest idea what part is likely to cause the output to almost halve.
Any ideas what I should check?
Here's a photo of the pcb: [url]https://drive.google.c... -
Re: New Members - please post your introductions here
Hi, I’m James from Australia,
I’ve been an electronics hobbyist for most of my life, with some training and employment in the field along the way.
I mostly work on arcade and video game systems.
I have great hand skills (soldering etc) but not so great faultfinding skills
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