PlaneWave Logo

Mechanical Design

High Resolution Axes Encoders

CAD-Image: High resolution axis encoder

PlaneWave’s A200 German Equatorial Mount comes standard with high-resolution Axis Encoders on both Right Ascension and Declination axes.

The A200 encoder technology is a breakthrough in value for a telescope mount using quality components usually founds in professional equipment costing thousands more.

The A200 uses a non-contact encoder design that offers high speed, reliable operation with zero friction and zero wear.

The encoders sits above a 20 µm thin flexible steel strip, which is gold plated to give high reflectivity and corrosion resistance. This ensured repeatable, precise results for the life of your mount.

Direct Drive Motors

Technical drawing of the direct drive motors in PlaneWave mountings
PlaneWave Astrograph in Baader Planetarium AllSky Dome in front of night sky

For added precision and accuracy the CDK700 not only uses high resolution encoders, but also employs a Direct Drive motor system. Direct Drive motors means that there are no gears to cause backlash or periodic error while slewing and tracking. With the high resolution encoders providing the feedback for the direct drive motors, not only will the telescope track without periodic error or have any backlash at all, but the mount will be able to counter against wind gusts. The direct drive motors can move the telescope at incredible speeds for tracking satellites or just to minimize target acquisition time.

The Direct Drive system is composed of 24 coils and 32 neodymium magnets powered by a 3-Phase Axial-Flux Torque Motor.

Combined with a hi-res encoder and stainless steel encoder tape on the circumference, the drive yields 16 million counts per revolution, or about 0.08 arcsecond resolution.

Test-Image of M1 (The Crab Nebula)

Test image: Addition of five 300 seconds exposures without guiding control.

5 images combined, Each 300 seconds unguided exposure.

Equiment: H200HR Mount, CDK17 OTA, STL1100 Camera, Baader 7nm H-alpha Filter

Location: Torrance, California (Los Angeles County)

Note: The image is dim due to the Narrowband Filter used to keep the brightest stars from saturating.