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Lesedi

524 bytes added, 10:56, 7 September 2020
=== Safety ===
Note that there is no hardware lockout for the telescope (except for brackets that can be fitted to hold the telescope vertical for e.g. primary mirror removal). All the subsystems' motors are brushless DC motors and remain powered up all the time; powering down the motors would leave the telescope and subsystems free to move under gravity or external forces (e.g. leaning on it). There is a '''dome lockout''', which is a physical switch in the dome that prevents the shutters and dome from moving. As a safety feature, '''the TCS disables all actions when the dome lockout is on''' and displays the warning shown in the image below. Before the telescope can be used from the TCS, you must ensure that it is safe to turn off the lockout, then do so using the switch at the North end of the pier in the dome. If observing remotely, you will need to call a technician to do this for you.
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[[File:LesediTCSlockoutSnippet.png|400px|frame|left|This message on the TCS indicates that the dome is locked out and the TCS cannot be used. The dome must be checked for safety before switching off the lockout and continuing.]]
Below is a screenshot of the main "Controls" tab of the TCS, where everything required for routine observing is located. There is one other tab, for more rarely used "Advanced" functions. The Controls tab is split into four main panels: command of the telescope and instrument selection on the left; the status of each subsystem in the middle; time and positional information on the upper right; and important buttons that need to be easily accessible on the bottom right.
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[[File:LesediTCScontrolsTabAnnotated.png|thumb|600px|frame|left|The main Controls tab of the TCS indicates the status of all subsystems; displays the time, telescope and dome position; gives access to a target catalogue; and allows control of the user to slew and offset the telescope, adjust the focus focus and select the required instrument selection.]]
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Clicking on the three vertical dots beside a subsystem displays a drop down list of further subsystem status info, as can be seen below "Dome" and "Rotator 1" in the central panel of the screenshot above. The ethos meaning behind the colour coding of subsystem status is as follows:
*'''Green''': a subsystem or state is either selected (e.g. in the screenshot above, the telescope is tracking at the sidereal rate, and the SHOC instrument is selected), or is in the correct state for observing (e.g. mirror covers open, dome shutters open, telescope tracking, dome tracking, rotator 1 (SHOC) tracking).
*'''Orange''': a subsystem is in an inappropriate state for observing. If the mirror covers or dome shutters are closed, their indicators would turn orange; likewise if the lights are switched on their indicators would be orange. In the screenshot above, Rotator 2's indicator is orange, which - this is acceptable because SHOC (selected in green on the left) is mounted on Rotator 1, so only Rotator 1 needs to track with the telescope. If the mirror covers or dome shutters were closed, their indicators would turn orange; likewise if the lights were switched on their indicator would be orange.
*'''Blue''': a parameter that has a numerical value but no right or wrong state is indicated in blue, e.g. azimuth or airmass.
==== Emergency Stop ====
It is important to note the '''Emergency Stop''' button, on the lower right of the TCS display. It is always visible on both tabs, and will stop the motion of the dome, shutters, telescope, rotators and secondary mirror. It will not stop the autoguider XY-slides, the mirror covers or the tertiary mirror. The Emergency Stop button should be clicked if anything that is moving is going to cause a hazard. Once clicked, the Emergency Stop button will be toggled to read '''Reset''', and you must ensure that it is safe to reset all the subsystems before pressing this button to continue.
==== The Startup button ====
The '''Startup''' button is not a "power-up" button, as everything all telescope subsystems should be powered up at all times. '''The Startup button should be used only when you intend to open up to observe, as it opens the domeand the mirror covers.'''  '''If you don't want to run the full Startup procedure''' (e.g. because it's daytime and the dome should not open), but do need to interact with the telescope, individual subsystems can be commanded from the Advanced tab. Buttons on the Controls tab will work without running Startup (with the exception of Shutdown), though the telescope will need to be "unparked" from the Advanced tab before it can slew. The Startup button runs a script that performs the following tasks in this order:
# Take remote control of the dome
# Switch off fluourescent fluorescent lights
# Switch on slew lights
# Open dome shutters
# Switch off the slew lights
You can watch the startup procedure from the webcam. The While the procedure is running, the button displays a revolving circle and the status panel on the Controls tab is updated as each subsystem is activated. Don't try to perform any other operation until the procedure is complete, when the text on the Startup button will be replaced with "Shutdown". The SHOC rotator is selected on startup to ensure that observations are not made with the tertiary mirror in an unknown position, so to use Sibonise you will need to select the instrument after the startup procedure has completed
'''If you don't want to run the full Startup procedure''' (e.g. because it's daytime and the dome should not open), but do need to interact with the telescope, individual subsystems can be commanded from the Advanced tab. Buttons on the Controls tab will work without running Startup (with the exception of Shutdown), though the telescope will need to be "unparked" from the Advanced tab before it can slew.
==== The Shutdown button ====
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