Hi FOGers,
?
This post is about the resolution of a problem that I experienced with my 2008 Felder CF741P (combination machine). The issue occurred (and was resolved) several months ago, so my apologies for being a bit late, but I've been busy...
?
As a quick background, in early 2023, I experienced a complete failure of my CF741. That issue, which took over 6 months to be resolved was a painful experience that I hope to never have to go through again. I have posted to this group about this issue last year, when I was in the middle of it. I won't dwell on that issue, other than to make 2 points related to it:
1 - I did receive significant, helpful advice from members of this group regarding this problem, and I deeply appreciate it.
2 - (This is pertinent to my story about a more recent problem and its resolution) - During the course of "troubleshooting" with Felder support staff, it was recommended that I replace a number of electrical components, that the techs suspected might be defective.? None of these new components fixed the problem, but I did accumulate an entire shelf of unused spare parts for my machine.
?
In February of this year (2024), the PowerDrive on my planer table quit working; just stopped mid-move, without warning. Since my Planer table was up at the time, this meant that pretty much my entire machine was unusable while this problem existed.?
I called Felder tech support, and over the course of a week or so, was handed from one tech to another, all who took the same approach as before: "trouble shooting", which meant telling me (via phone) to open the electronics compartment and take voltage/continuity readings at points that they directed me to. Each time, the results were inconclusive: some of the readings appeared to be correct, others were wrong & really weird. I was really afraid that this problem would take another 6 months to be resolved.
?
Then, after about 2 weeks, I was connected with still another Felder technician (I cannot remember his name right now, but IIRC he was based in Texas). This time, after I explained (again) what the symptoms were, he directed me to the page in the CF741 schematics that included the Planer PowerDrive motor control. I am not an expert in electronics - completely the opposite. I knew what a schematic was for, but had no idea how to interpret it. And this page, to me, was extremely confusing. Expecting another "troubleshooting" session, I got out my voltmeter.
?
And here is where history did not repeat itself. The tech told me to put down the voltmeter, and spent the next 2+ hours on the phone to me, explaining the schematic. At the outset, he told me that he was going to explain the schematic to me, so that I could fully understand the working of this circuit. That was his plan - to teach me (a complete electronics noobie) to understand how this circuit - the circuit that had failed - was designed to work.
?
After 2+ hours of repeat questions, answers, more questions, explanations, etc. I was beginning to understand how the circuit was supposed to work. This guy's patience was truly amazing BTW. At the point where I was finally beginning to see the whole picture, he told me that he had to go, but suggested that I keep studying the schematic, to fully understand it. He suggested that, once I felt comfortable with the schematic, I might try using the voltmeter to verify that various portions of the circuit were working correctly.
?
The next morning, I went down to my shop, powered up the CF741, took out my voltmeter, and began tracing the circuit, while following the schematic. I started at the place where primary power entered the circuit, which was a large-ish assembly including a transformer and a number of other parts. The transformer produces AC current in a range of voltages. Power there was good. From there, I followed the circuit through the maze of switches and other components, point by point (everything looking correct), until I came back to the original transformer assembly. At this point there is a part (rectifier?) whose job it is to transform AC current into DC current.
The (AC) point entering this part showed the correct AC voltage. The (supposed to be DC) point immediately past this point showed garbage. Weird, very small values that kept changing and were nowhere near the spec.? Apparently that rectifier was not working.
?
Now, remember my shelf of spare parts left over from the previous year? One of those parts was the exact transformer assembly as the one that had apparently failed in my machine. One hour later, after carefully replacing the old assembly with the new one, I again powered on the CF741 and.... everything was working again. Boom.
?
So I'm back to work. And I learned a lot. I also learned that for Felder, and perhaps other technical support groups, there might be a better way to provide remote field service than their standard "troubleshooting" approach.
?
All of this reminded me of an old proverb, and I will conclude with it:
?
"Give a man a fish, and you feed him for a day. Teach a man to fish and he can feed himself for a lifetime"
?
Best regards,
?
Gerry Kmack
?
?
Gerry Kmack