Automation Phase 2 – Power

Automation Phase 2 - Power

Being able to remotely power up the various components of the observatory is very appealing, and while there is an argument that says until I have the roof sorted there is no point in doing this, I think that getting this element of the project done will be relatively low cost, fairly straight-forward and will seem to move the project along quite a long away.

If I waited until the roof was complete, I would still need to be outside - in the cold! At least this way, I would only have to nip out to open the roof!

Timeline of Activities

2nd December 2016

I now have the Vellemen VM110N and VM129 boards! Yay!!

I spent the weekend of 3rd/4th December installing Visual Studio 2015 Community edition, and learning some very basic VB .Net! I managed to write a simple application that enables the digital output channels on the VM110N - it's by no means elegant code but it's perfectly functional and allows me to take the next step of combining it with the VM129 to activate the relays.

The VM129 has eight output channels, so I will be using:

  • Ch 1 :- Main 12v supply
  • Ch 2 :- Mount
  • Ch 3 :- Camera
  • Ch 4 :- USB Hub
  • Ch 5 :- Dew controller

Eventually, there will be one channel for the flats panel, which will leave two spare. One of these will be for the roof control at least - but I don't know yet if only one channel is needed (roof open or close) or both (roof open, roof close). I'm still quite away from having the roof sorted (see Phase 3 page)

Still, this is very exciting stuff as it means I can now start planning how this is going to fit into the observatory and try and think through some of the other questions that I've detailed before...

15th September 2016

No real progress on this phase, except to have been thinking about cable runs and containment, where the RCD unit will be located, best position for the flat field box....

13th September 2016

Thoughts given to the automatic flat field process. There are a couple of options here:

  • Create a custom script that switches the right relay on, when CCD Commander is ready to take the flats. It will park the scope at the right place before taking the flats, and then fire the script to turn on the power - and off once the flats are taken
  • Have the power to the flat field light box on, but the circuit is interrupted by a couple of magnetic switches on the mount. The circuit is therefore not completed until the mount is parked in the correct position

The scripting option is, essentially, zero cost but makes the assumption that I can actually write a suitable script to operate the switch. The second option is more straight-forward but will have a small cost attached... I think, once I have the switching boards in my hands, and the ASCOM drivers installed, I will make a decision then - both options are appealing at the moment!

11th September 2016

So far, I have looked at the switching circuits needed for the various power elements. Again, a huge thanks to Steve Richards at The Chanctonbury Observatory for his unwavering patience in the face of relentless questions!

I know which components I need and have identified a suitable 15amp 13.8v regulated power supply. I now need to start planning the cabling runs in the observatory, and in particular where the switch box will be situated.