20+inch+F4+installing+the+new+servo+system+drive

The telescope drive system has been upgraded from [|Mel Bartels stepper system] to a new servo system by [|Sidereal Technology].

The slew speed can be as high as 16 deg/sec, but this has been lowered to 1.4 deg/sec (stepper system was less than 1 deg/sec) to enable the dome drive to keep ahead slightly.

Safety cut off limit switches are installed on Azimuth and Altitude. Additional limit switches have been installed along with the magnetic Azimuth sensors to prevent the telescope running past the dome Azimuth sensors.

These have been installed just in case of runaway's in telescope Azimuth, or the dome stops for some reason (dome motor failure or dome freezes to the dome ring/skirt....this has happened!). This could not have happened in the stepper system. Stalls were more common in that system.

Spreassheet deals with gear ratios of the new system.

New control system layout:-

Some pointing runs have been done using PointXP. Results of these can be seen in the Software configuration page.

More to follow:-