G5500 AZ/EL controller Glitching?
What is the cause of intermittent glitching on the G5500 rotor controller?
Every now and then (and only when transitioning the LEFT switch), BOTH positioning meters jump down about 10%. And then with a few more flips of the switch, you can get it back.
Apparently the internal 6v supply is dropping since both meters glitch down and an externmal voltmeter on the rotator feedback terminals also show the same10% drop in the 6v line. (though it appears to be a constant 5.5 volts not 6) And then glitches down from the 5.5.
Also noticed the Adjust voltage pots on the back do not change anything.
Sorry, I know we see these same questions ALL the time, but this is the first time in 20 years for me… and when Mine wasn’t broke, it was easy to ignore all the emails…
Bob
Bob,
My guess is that since it is only when turning Left, the problem is with the "bow-tie" or something mechanical in the break that is causing a lot of drag on the motor when turning left. Try measuring the voltage between lug 6 & 4 turning left and compare to the voltage between 6 and 5 turning right. I suspect the load or drag is drawing down the secondary side of the AC transformer, affecting both the feed back circuits and the drive motor.
Easier said than done, since as you state the issue is intermittent and the switching action clears the problem.
When you say the voltage pots do not change anything, I suppose you mean adjusting them does not fix the problem. That is, it is not a dirty pot issue.
BOB KO6TZ
Apparently the internal 6v supply is dropping since both meters glitch down and an externmal voltmeter on the rotator feedback terminals also show the same10% drop in the 6v line. (though it appears to be a constant 5.5 volts not 6) And then glitches down from the 5.5.
Also noticed the Adjust voltage pots on the back do not change anything.
When you say the voltage pots do not change anything, I suppose you mean adjusting them does not fix the problem.
No, I mean they do not affect either AZ or EL meter reading. Turn pot end-to-end and meters still correctly read the AZ and EL and an external voltmeter does not show any change on the We used the full scale pots to calibrate the system, since the volts adjust pots do nothing..
Further, when the 10% glitch happens, it stays down permanently even with the motors not turning and no fingers on the switches... until it glitches back up eventually..
Thanks Bob
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of KO6TZ Bob Sent: Friday, November 18, 2016 5:01 PM To: amsat-bb@amsat.org Subject: Re: [amsat-bb] G5500 AZ/EL controller Glitching?
Bob,
My guess is that since it is only when turning Left, the problem is with the "bow-tie" or something mechanical in the break that is causing a lot of drag on the motor when turning left. Try measuring the voltage between lug 6 & 4 turning left and compare to the voltage between 6 and 5 turning right. I suspect the load or drag is drawing down the secondary side of the AC transformer, affecting both the feed back circuits and the drive motor.
Easier said than done, since as you state the issue is intermittent and the switching action clears the problem.
When you say the voltage pots do not change anything, I suppose you mean adjusting them does not fix the problem. That is, it is not a dirty pot issue.
BOB KO6TZ
Apparently the internal 6v supply is dropping since both meters glitch down and an externmal voltmeter on the rotator feedback terminals also show the same10% drop in the 6v line. (though it appears to be a constant 5.5 volts not 6) And then glitches down from the 5.5.
Also noticed the Adjust voltage pots on the back do not change anything.
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participants (2)
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KO6TZ Bob -
Robert Bruninga