Turning on an A/C system in preparation of imaging

I am wondering if somebody could give me their thoughts and ideas for my observatory and for my dragscript to accomplish this. My Observatory (Dome) has its own AC “Split” cooling system. Many might think using an AC system in the observatory is crazy (and expensive!) but that’s another matter completely. It is a luxury I have enjoyed when on rare occasions I am literally working in the observatory during a hot summer day. But then there is this: I would also think it is beneficial to get a head start on mirror cooling. The attempt is to match the observatory to what is likely to be the outdoor temperature at the time of astronomic night. I would want it (based on dome temperature) to turn on automatically roughly 2 hours before night. I would want it turned off for the rest of the night once, 1) the shutter is opened and/or, 2) roughly 3 hours later regardless of the shutter being opened. Even when the shutter remains closed the metal domes drop toward ambient rather quickly. So there is little need once nightfall is established. So another parameter to determine when to turn it off is simply to follow the ambient-indoor temperature delta. I obviously want it operating as little as possible since it’s wasteful.

So, I welcome general opinions about whether this even makes sense. Also, of course, I always welcome dragscript and I/O ideas. This observatory’s computer has a double instance of Viking, a tool I find indispensable.


I am based in the UK, and have a remote observatory that I built in the Negev Desert in Southern Israel. Air-conditioning is absolutely essential. From the onset, I used SENSIBO Sky web controller.
Fault free after 5 years being used everyday. I can supply more info if required, but they have a good website, and for the few times a had a setup issue they replied right away.
I hope that helps
Adrien Richardson

You should be able to accomplish this without the need for Voyager control. One option would be to use a smart outlet, and a thermostatically controlled outlet (like this one: https://tinyurl.com/bdnu6mcs )

Plug the smart outlet into mains, and use its app to set a time to turn on 2 hours before imaging, and then have it turn off at say midnight.
Then plug the thermostatic outlet into the smart outlet, and set the temperature to cool to.

So, at the start time, the smart outlet will turn on, and if it’s too warm, the thermostatic outlet will turn on the AC. Once the AC has cooled enough, or ther temperature has dropped due to nightfall, the thermostatic outlet will turn the AC off. At midnight, the smart outlet will turn off so the AC won’t start up again in the morning.

Thank you on the SENSIBO idea. The Negev Desert! Absolutely awesome.

True! But using my script based on Perpetual I still prefer having Voyager/Viking in control of this as well could offer me some additional options. Also I do use and enjoy KASA plugs and find them so easy to utilize. I am trying to investigate some scripts that others have written for Dragscript to control KASA.

scripts that others have written for Dragscript to control KASA.

Very cool! If you find some, post somee links here. I’d be interested too. :slight_smile:

This is a very tardy response to the topic regarding KASA.

Rewsteruk has not only written a Windows based GUI app for the KASA devices, TP-Link Kasa Control – Smartplug/Smartbulb Control for Windows – Rewster.UK
He also has a separate command line app as well, TP-Link Kasa Control Command Line -Smartplug/Smartbulb Control for Windows – Rewster.UK
These and the Tp-link App on which it is based can be downloaded for the Microsoft Store.
I successfully utilized his KASA command line App into one of my dragscripts.