Build Your Own observatory

This provides a list of things which we found reliable for a fully autonomous and remote (more then 10 hours of drive/flight away) observatory. All devices listed here are fully supported and integrated into RTS2. This list expressed our experiences - it is possible better solutions are available, but we haven't found them yet. If you find one, please let us know.

Cloud sensors are great in keeping your observatory dry. By detecting clouds before rain start, they can save you a lot of troubles.

• Mrakomer 4.1 slightly expensive then AAG, but most probably best choice.
• AAG most probably worse but cheaper then previous one, may be sufficient.

After some research, we believe that this is the best rain sensor:

• ThiesClima http://www.thiesclima.com/precipitation-monitor.html

It has all features we consider important:

• you can choose if Rain should be signaled by closed or opened circuit
• opened circuit if it failed - fail safe operation
• it works reliably, requires low maintenance

In our experience the best is to connect this sensor directly to PLC for dome control - see bellow.

We found that smart programmed PLC is a must for dome automatization. After some research, we believe that Zelio Smart Relays fit the bill perfectly. We provide our programmes for those PLC, which you are free to modify and use - or contact us if you need some modification.

• Zelio Smart Relay, programming software (unfortunately Windows only, but GUI runs under Wine and the plan is to port software downloading as well) available at Zelio download pages. You will need 24V modules to benefit from SR3 NET01BD network module integration.

If you will look for another PLC driving your dome, watch for:

• Easy PC interface (network prefered)
• PLC programming - traditional Ladder Logic style does not fit our needs, we prefer FBD (Functional Block Diagrams)

For Zelio description, FBD sources and more: http://rts-2.svn.sf.net/viewvc/rts-2/trunk/rts-2/src/dome/zelio/