Servo Setup - Balance

[sollner77]

Here's my situation:  As of two nights ago, I was able to image for 10+ minutes without guiding - no trails, round stars.  I had meticulously hand-balanced the mount on both axes in multiple configurations - afterward, with motor off, nudging the mount to move in both axes resulted in smooth and effortless movement in all directions, stopping with no telltale off-balance movement.  Come last night, with no changes to the setup, the mount vibrates intermittently and creates disturbing sound effects.  Checking the balance, all is well, no change from my earlier remarks.

 

I have tried to use the balance function before, but when the bars are aligned the system is seriously out of balance in all positions.   Admittedly, I am still a novice at this and may not be performing the Servo balance function properly - my results certainly support that.  Any help in resolving my "in balance" out of balance would be appreciated.

[nakbrooks]

I have had exactly the same noise and vibration on my DDM85XL occasionally when it was supposedly in balance and tuned, although this has always been after I have re-balanced. Not sure what causes it but I have managed to get rid of it by playing with the tuning.

[Jay]

I'm not sure if it's possible to balance the mount well enough manually without using the "balance function graphs". I wonder how well the mount is actually balanced if the alignment of the graphs is way off. Also the graphs have to aligned in all different mount positions not just in one position.

 

One thing I've noticed with some (heavier setups) is that I can't use the noise filter (especially RA axis) without getting lots of strange noise and vibration. Turning the filter OFF solved the problem.

 

Jay

[Wojtek Gdańsk]

Welcome. Your problem of vibration and noise DDM 90% is caused by bad motor PID settings , you have to work a little bit in the PID settings . I am now on a business trip and I can not check on my DDM60 how PID may account for this anomaly engine but had the same problem as you. As for the noise filter axis RA - On my DDM60 is installed C14 HD and also in the axis of the RA I have a problem with this filter , I can not be set using the filter high PID parameters , this problem occurs only in the axis RA axis DE I do not have any problems with the filter can be set as high as the PID parameters . Some time ago I reported this problem to the company ASA , the company wrote back to me that I do not have to necessarily use the filter in the RA axis - admit that it is a little strange answer. I believe that if there is such a function as filters in the RA axis and the axis DE they should work without problems in both axes. I f the answer ASA is a bit strange . Luck in PID parameter settings .

Regards , Wojtek

Edited March 8, 2014 by Wojtek Gdańsk