13) DOME mode
13.1 - Conventions used in this manual
Azimuth angles
Here is how azimuths are coded :
Nord
: 0°
Est
: 90°
Sud
: 180°
Ouest
: 270°
Azimuth drive direction
There is no specific convention there. Positive is one way per your wish, negative the other way.
13.2 - Pre-requisits
Before installing Doe Tracker, your dome should be able to :
-
rotate one way with a continuous pressure on a button (or a relay closed)
-
rotate the other way by pressing another button or closing another relay
-
optionnally to open and close the dome shelter : with a temporary pressure on a button (or
relay closure) ; this pressure triggers the shelter opening or closure but the pressure length
is not taken into account by the Dome Tracker. The shelter should manage on its own the
opening/closure times and end-of-course switches.
The Dome Tracker can trigger the opening/closure with a specific duration (user parameter)
but the shelter should have its own protection (usually on/off switches)
13.3 - DOME hardware setup
Operating principle : initialise and rotate the dome
A close sensor (sensing when a metal plate comes in front of it) will initiate the reference position of
the dome. It doesn't have to be when the dome is on azimuth zero. The reference position sensor is
in general located when the dome is close to its parking position. This way, the system will be able
to move the dome from the parking position to the reference position quickly to initialize the dome
position. It can be done at the beginning of every night or from time to time.
To rotate the dome, Dome Tracker closes a relay to turn one way and close another relay to turn the
other way until the rotational coder position is at the target position calculated by the software. The
relay is then re-open (connector J15 on the schematics).
Operating principles : shelter open/close
This is an optional feature. A brief contact of pins 3 & 4 of J16 connector (fig. 1) should trigger
shelter opening. Brief contact of pins 1 & 2 should trigger shelter closure.
Attention ; thoses contacts last for 1sec in general, you can change the duration if needed for your
setup. Dome Tracker will not manage end-of-run switches.
It is possible to connect those two relays (J16) to a radio controled system to avoid wiring between
the shelter and the dome base itself.
Guide Utilisateur / User Manual - Dome Tracker– DC0007C 37 / 60
