• Never use fluorescent lights! They are one of the strongest sources of electrical noise.
• Reed (magnetic) proximity switches are very useful to check for roof and mount position. Any will work with the Dragonfly. The inexpensive ones we've found the most reliable are the ones available from RS Components with ref. 289-7783 (don't forget to get the magnet, ref. 289-7812).
• If using push-buttons to detect roof position (such as RS ref. 746-8605), the usual way is to place the push-buttons in a fixed position (wall), and the part that will press them—a plastic angle is suggested, as it can bend and won't damage the push-button—on the moving roof.
• The above sensor suggestions are some we've tested and confirmed worked fine under normal conditions. Also, properly configured, you'll get an error from the software in most failure cases. It may, however, be reasonable to go for high-quality ones in truly remote observatories or with very expensive equipment. It is difficult nowadays to separate the good quality from the not-so-good, but no doubt very good sensors are readily available.
• Plan carefully, be redundant if at all possible, and have a UPS strong enough to close the observatory in case of power failure.
• A simple external relay can be used to detect power failures and maybe force closing the observatory. These and many more useful tips are available on our "more information" webpages.
• Every Dragonfly has an internal web—it can be used to get system information, check sensors and change relays, and to update the system in the case of the Dragonfly 2. It can be accessed by simply pointing your internet browser to the Dragonfly's address, by default: http://dragonfly.