Hi all,
Just a brief (?) update to say that
the new MOSFET solution I discussed last week has passed all of the tests I have come up with so far, including several situations that caused the previous MOSFETs to fail a high percentage of the time.
I installed the new LR7843 chip on several different testing units. It has been working very reliably all week and I did not experience any failures of it during testing; so far, so good.
It looks like a viable solution, so I have decided to move forward with it. I have been fighting this issue since mid-February, and it has been a tremendous PITA for me and my users. I am very eager to see if this new solution truly solves the problem(s) and allows a much higher percentage of these heaters to survive in the real world.
One comment: I have noticed that the LR7843 chip heats
slightly less aggressively than the NVG5890N chip it replaces. In practical terms, I have found in my testing that the new chip needs an extra second or so of heating time to achieve a similar level of heating as the old chip. I mention this because a) it's true, and b) some of us are obsessed with this sort of minutiae, so I want to be as transparent as possible about this change. Some people found the previous NVG5890N chip to be
too aggressive, however, so a slightly less aggressive chip is probably a good thing.
I am
finally satisfied that I have a solid solution for the Flux Deluxe's MOSFET failure issue. Now, this probably means I'm just setting up all of us for more pain on this issue, but I'm very ready to see how well this new chip performs in the real world, so
I have begun installing it on the heaters I have been waiting to repair. As of this afternoon I am about half way through that queue: I have fixed five heaters so far, and have another six to go. I'll complete those tonight and tomorrow, and will ship the repaired heaters back to customers on Monday. I'll send tracking numbers once they go out.
Early next week I'll share some new features and improved construction techniques with you, which I think you'll appreciate, and will also start making new heaters again. More on all of that coming soon!
This has been a grind, but I know a lot of you are eager for one of these heaters, so I have been reluctant to give up on the design. Thanks again for your support and patience while I plowed through this!
I am hopeful the future will be at least a little a bit smoother.
Cheers,