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5. Remote Observing
5.1 Introduction
Remote observing with the Parkes telescope from the Marsfield Science Operations Centre (SOC) which commenced in December 2012, and is expected to be the default mode of observing by the start of the 2013 APR semester. Observing from Parkes will still be permitted for complex or non-standard observations, or in other circumstances where this is the more sensible option. Observers who have successfully observed from the SOC will be permitted to carry out subsequent Parkes observations from other remote locations: all observers must observe at least once from the SOC in order to become a qualified Parkes remote observer.
An introduction to the SOC is available here.
5.2 Remote Observing Support
Note that the support model outlined below will be from the start of the APR13 semester.
The remote observer in need of assistance should, in general, consult these in the order given below.
- The Online User Guide.
- The designated Project Expert. This is equivalent to the DA role at Narrabri, but specific to the project. This is usually an expert observer of the Parkes Telescope.
- During business hours only, a rostered member of the Parkes SO staff can contacted if the issue is beyond the knowledge of the Project Expert.
- For emergencies, a member of the Parkes Call-out Rapid Response Team.
fig:remote_support shows the flow of support as defined above.
Figure 5.1: Remote Observing Support Model.
5.2.1 Role of the Remote Observer
The role of the Remote Observer is to monitor the progress of the observation and the condition of the telescope and collected data through a variety of interfaces. During the observation, this monitoring is the remote observers’ primary responsibility.
The state of the telescope is monitored by its automated protection system, the TPS (Telescope Protection System). The TPS monitors the critical telescope systems, and acts in favour of the safety of the telescope if adverse conditions are detected. Its actions include stowing the telescope or disabling its motion, switching between alternate power sources for the telescope and initiating observatory staff intervention. Monitoring displays used for observing will inform the observer of any action taken by the TPS.
5.2.2 Role of the Project Expert
Each team is required to nominate the Project Expert at the time of the proposal submission. This is an astronomer who is an expert observer of the Parkes Telescope for that specific observing mode. Tasks of the Expert are:
- To train the Observer to Remote Observations in case of First Time Observers or
Observers who have not conducted observations with Parkes in the last 12 months. This
usually happens either at Parkes or at the SOC and includes training on:
- Setting up schedules
- Setting up the observations
- Startup observations
- Assessing the data quality
- Support the team observations. The Expert will set the time range he/she can be contacted.
- To contact the rostered team member of the Science Operation support in case of need (business hours only, 8:00-16:00 weekdays only).
- To contact the Call-out person in case not able to handle an issue not related to the telescope safety (only 07:00 to 23:00 Monday-Friday, and 08:00 to 18:00 Saturday-Sunday and Public Holidays).
- Call the Call-out person for any perceived threats to telescope safety at any time.
5.2.3 Role of Science Operations
- Construct and publish the Parkes observing schedule and Online User Guides.
- Manually override the handover mechanism when needed.
- Participate on the roster of SO Call-out to give support to the Project Experts (business hours only, 08:00-16:00 weekdays).
- Train Project Experts.
- Be part of the Emergency Contact team.
- Call the Emergency Call-out member of the Parkes Rapid Response Team for any perceived threats to telescope safety at any time.
5.2.4 Emergency Call-out Person
The Emergency Call-out Person is part of the Parkes Rapid Response Team which comprises members of the Parkes staff equipped to solve or assist in solving telescope safety issues that TPS cannot address. At all times one member of the team will be on duty. They will be contactable by the TPS, by staff in EO or SO, and by the remote observer. The role of the Call-out person is two-fold. The chief role is to assess any emergency situation brought to their attention, and if necessary call for assistance from other members of the team or from emergency services (eg. local fire brigade). The sequence to be followed is:
- Acknowledge TPS call.
- Assess the nature of the Alarm on the TPS (and other sources of information like the VNC sessions).
- Take action on the TPS panel, if appropriate.
- If necessary, travel to the telescope, and if safe, enter the tower.
- Assess the situation to establish the source of the alarm and any other factors that have bearing on the situation (if not done in item 2 above);
- If necessary and safe, take control of the telescope.
- Either act to remove or mitigate the threat, or call for extra assistance.
- Log the response in the Call-out log.
- Advise the observer on the likely course of action to return to normal operations.
- Once the situation is resolved (possibly hours later), return the TPS to its normal operating condition (various inputs may have been isolated as part of the response) and hand the telescope back to the remote observer.
- Make a final log entry to close the event.
It is planned that the Call-out person will be located at the Observatory for the first term of remote operations, and be able to respond to calls and be at the telescope within 10 minutes of the call.
5.3 Before You Observe
The remote observer will need the following:
- An active CSIRO login account. To establish an account, follow the instructions here. Allow 5 working days for the account to be established.
- To book as remote observer for the scheduled observations at the Observing Portal, tab “RemObsBooking”. A confirmation will be sent by email. Resources for remote observing are available from the Observing Portal.
- To complete the online observer training if instructed to do so in the confirmation email.
- To complete a full Remote Observing Training if not trained for remote observing in the last 12 months. Otherwise, especially if first-time remote observers, you will need to conduct an observing session at the SOC in Sydney under the supervision of a trainer before being qualified as Remote Observer.
- To have a project requiring a standard configuration. If the observation is non-standard, the observer is required to come to the SOC or Parkes at least for the first run of the project to support the non-standard setup (if required) and/or be trained in the use of the special observing setup the project requires.
-
A computer with the following:
- Access to the internet;
- A recent version of a commonly used operating system.
- A version of VNC viewer, TightVNC (Windows) or Chicken of the VNC (MacOS X).
- A web browser that supports HTML-5 and has javascript enabled; supported browsers are: Firefox v16+, Sarafi v6+ and Chrome v23+. Internet Explorer (any version) is NOT supported.
- A screen size at least 1920 x 1200 is recommended; a multiple screen setup will be beneficial for more complex observing setups for observing from places other than the SOC (i.e., where two instances of TCS are required).
5.4 Stowing and Unstowing
Note: If you are unstowing the telescope for observing, you must first follow the following procedures:
- Login in and check the chat utility is available on the Observing PORTAL.
- Check that the Telescope State is set to “OBSERVING” (on the chat utility.)
- Establish a dialogue with the current contact via phone call from details provided on the chat utility via the Observing PORTAL.
- Once permission to observe is obtained and the antenna is handed over to you, you need to register as the observer in charge via the Observing PORTAL.
- Follow the appropriate handover procedure as outlined below.
With the MCP in Computer Remote, you can stow/unstow the antenna using TCS. Under the "ACTION PANEL" (top right of TCS GUI), you press the "Stow" button. Once complete, this will disable the drives in Azimuth and for Zenith, the antenna will drive to the Zenith Stop position (~ -0.54 deg) and put in the locking pin. Note the safety timer will also be disabled.
To unstow the antenna, press the "Unstow-ExLim" button on TCS, under the "ACTION PANEL" section, top right on the TCS GUI. This will remove the Zenith locking pin, drive the antenna out of limits and leave both drives enabled. Note again, that the MCP must also be in Computer Remote.
Note: You can only start observing with TCS if the Zenith angle is greater than 1.2 degrees.
5.5 Handover Procedures
This section provides detailed checklists of the handover procedures for the different type of situations that can be met:
- Staff-to-Observer
- Observer-to-Staff
- Observer-to-Observer
- No Operator-to-Observer (start with antenna stowed)
- Observer-to-No Operator (end with antenna stowed)
- No Operator-to-Staff
- Staff-to-No Operator
An example of “No Operator” is when the an Observer takes control after a Green Time period. Here, “Staff” refers to Science and/or Engineering Operations staff, located at the Parkes site.
The above that are relevant to observing are described below, but users should consult the full procedures for remote operations here.
5.5.1 Staff-to-Observer
- Staff safely sets MCP to “Remote”;
- Staff sets the antenna state to “OBSERVING” on the Observing PORTAL;
- Staff makes the VNC sessions accessible from outside (e.g.: changing back the password to that known by the users);
- Staff and Observer communicate via chat/phone and agree on handing over the antenna (N.B.: it is recommended this occurs via telephone for the initial period of remote operations);
- The Observer places their contact details on the Observing PORTAL;
- The Observer takes control of the antenna by logging onto the VNC sessions;
- Observer sets up the observations (see User Guide for details);
- Observer conducts the observations.
5.5.2 Observer-to-Staff
- Staff contacts the current Observer via phone or chat utility – (N.B.: it is recommended this occurs via telephone for the initial period of remote operations);
- Staff and Observer agree on when to hand over the antenna;
- Staff takes control of the antenna;
- Staff makes the VNC sessions unavailable to observers (e.g., killing the VNC sessions and changing the password);
- Staff sets the antenna state to “MAINTENANCE” on the Observing PORTAL;
- Staff operates the antenna for local activity (either Maintenance or Reconfiguration);
5.5.3 Observer-to-Observer
- The new Observer contacts the current Observer;
- The two Observers agree on handing over the antenna (time, how to leave the antenna, et cet.);
- Once the above is done, the new Observer registers themselves as the observer in charge via the Observing PORTAL;
- N.B.: if the current observer is not contactable, the new Observer can take control of the antenna at the start of the project scheduled time;
- The new Observer takes control of the antenna;
- Observer sets up the observations (see User Guide for details);
- Observer conducts the observations.
5.5.4 No Operator-to-Observer
(N.B.: to further investigate whether this procedure - combined with the others, e.g. Staff-to-No Operator - is sufficiently safe.)
- The new Observer checks that:
- No one is in charge of the antenna (no details on the chat utility).
- MCP is set to “Remote”
- The antenna state on the Observing PORTAL is set to “OBSERVING”;
- The antenna is either stowed or stationary.
- The Observer registers themselves as the observer in charge via the Observing PORTAL.
- The Observer takes control of the antenna;
- Observer sets up the observations (see User Guide for details);
- Observer conducts the observations.
5.5.5 Observer-to-No Operator
- The Observer ends the observations.
- The Observer checks not having been contacted on the chat utility.
- The Observer Stow the antenna (via TCS, see User Guide).
- The Observer quits TCS and the Backend GUIs used.
- The Observer clears the contact details in the chat utility.
- The Observer quits the VNC sessions.
5.5.6 No Operator-to-Staff
- Staff checks that:
- No one is in charge of the antenna (no details on the chat utility)
- MCP is set to “Remote”
- The antenna state is set to “OBSERVING”;
- The antenna is either stowed or stationary.
- Staff takes control of the antenna by;
- Staff makes the VNC session not available to the users (e.g., killing the VNC sessions and changing the password);
- Staff sets the antenna state to “Maintenance”;
- Staff operates the antenna for local activity (either Maintenance or Reconfiguration);
5.5.7 Staff-to-No Operator
- Staff safely sets MCP to “Remote”;
- Staff sets the antenna state to “Observing”;
- Staff makes the VNC sessions accessible from outside (e.g.: changing back the password to that known by the users);
- Staff stows the antenna, leaves it under remote control, and leaves a message on the chat utility that the antenna is ready for remote observing;
- Staff clears the contact details in the chat utility.
- Staff quits the VNC client used.
5.6 Using VNC from the SOC
Parkes Observing from the Science Operations Center (SOC) is done in a dedicated room with three monitors connected to the machine PYXIS. The username and password can be obtained from SOC observing support.
The recommended layout for observing is shown below in fig:vnc_servers. Please try to stick with this layout.
Figure 5.2: Using VNC from the SOC.
The VNC servers on joffrey are run as user PKSOBS. Prior to observing, ensure:
- Have logged into the Parkes Observing Portal and FROG.
- You have contacted the current observing team (or local Parkes staff member) that is listed in the Welcome tab of the chat utility, located in the Parkes Observing Portal.
- On the Welcome tab of the Portal, click on the regitration of current observer/staff and enter your details.
Once the above is done, open two terminals, one in each screen on the SOC Parkes observing machine (PYXIS) and type the following:
vncviewer -shared [-noraiseonbeep] joffrey.atnf.csiro.au:1 in the first screen,
vncviewer -shared [-noraiseonbeep] joffrey.atnf.csiro.au:2 in the second.
The -noraiseonbeep should be used if you do not like beeping terminals to
take focus. The VNC password is available from the SOC Parkes observing desktop,
or from staff.
The third screen should be used to dislay the following: FROG and the OBSERVING PORTAL. If you are observing in Pulsar mode, you may also connect to the Pulsar Online Monitor.
Other Pulsar backends:
Do NOT use a VNC session web browser to connect to the Observing PORTAL, FROG or other Pulsar monitoring systems.
5.6.1 VNC startup on joffrey:1
Assuming you are starting up for the first time, ensure the following are present on JOFFREY:1.
5.6.1.1 TCS primary
On JOFFREY:1, in the first virtual window.
If TCS is already running, it is recommended you close it and exit the terminal (especially if interleaving projects are pulsar and spectral/continuum in nature.) Open a terminal on joffery and type the following:
-
tcs.
From the startup GUI, select the relevant mode for your observations (and select the expert mode). Select the relevant recall state if there is one. For example:
- For DFB3/4 spectral–line/continuum observing select:
- DIGITAL F’BANK (time binning)
- EXPERT MODE
- SELECT PROJECT (if present, via bottom menu)
- For Multibeam Correlator spectral–line/continuum observing select:
- MULTIBEAM CORRELATOR
- EXPERT MODE
- SELECT PROJECT (if present, via bottom menu)
- For Pulsar observing select:
- Pulsar observing modes.
- EXPERT MODE
- SELECT PROJECT (if present, via bottom menu).
- Once open:
- Select the relevant PDFB (DFB3 or DFB4).
- FOLD or SEARCH MODE
- SELECT relevant schedule
- Focus: Enable
- Antenna: Enable
If the antenna doesn’t enable, likely it means that either another TCS is still running with antenna enabled (which takes the antenna control) or other software is controlling the antenna (like PMDAQ used for PSR obs with the Analog Filter Banks).
- Auxillary: Enable
- Correlator: Enable
- Sched agent: CTRL for Spectral-line/Continuum and GUI for Pulsar
- Sched files (Spectral–line/Continuum observations).
- Click on Sched file and select OWN, then select the schedule file.
- For Spectral-line and Continuum projects. Schedule files are located in /home/pksobs/Projects/PXXX/ or /nfs/online/local/tcs/sched/pXXX .
- For Pulsar projects, schedule files are usually located in /psr1/tcs/sched/ .
The indication that this is TCS primary is shown on the title bar of the TCS GUI.
5.6.1.2 TCS alternative
On JOFFREY:1, in the second virtual window.
If you are using another instance of TCS (i.e., you are using DFB3/DFB4 simultaneously), open a MYRCELLA terminal (right–most terminal icon on taskbar) and type:
-
start_alt, then -
tcs alt.
If you are NOT using another instance of TCS, you may use this virtual window for other purposes, but note anything you open may be closed at the start of the next observing session. The indication that this is TCS alt is shown on the title bar of the TCS GUI.
It is important to note that if TCS primary is running DFB3, then the alternative TCS must use DFB4. The same DFB cannot be used by both TCS’s.
It is important to note the dummy antenna systems are started by
start_alt, otherwise file header parameters will be incorrect.
Note that start_alt kills existing processes before restarting them.
Note that for Pulsar projects, schedules such as the following should be used: P456_MB_PDFB4A.sch (note the A for alternate.)
5.6.1.3 LOBOSS, LOGUI and OPERFCC
On JOFFREY:1, in the third virtual window.
On the bottom panel, click on "Observing Tools" and start LOBOSS, OPERFCC and LOGUI.
5.6.1.4 PKMC
On JOFFREY:1, in the fourth virtual window.
On the bottom panel, click on "Observing Tools" and start PKMC.
5.6.2 VNC startup on joffrey:2
Assuming you are starting up for the first time, ensure the following are present on JOFFREY:2.
5.6.2.1 DFB3
On JOFFREY:2, in the first virtual window.
If using DFB3, on the bottom panel, click on “Backend Tools” (twice) to open two ssh connections to pkccc3. Now do the following:
-
corkillin the first terminal, to terminate any existing processes, then -
spd -
sdfb3for continuum/spectral-line projects OR -
pdfb3for pulsar observations.
5.6.2.2 DFB4
On JOFFREY:2, in the second virtual window.
If using DFB4, on the bottom panel, click on “Backend Tools” (twice) to open two ssh connections to pkccc4. Now do the following:
-
corkillin the first terminal, to terminate any existing processes, then -
spd -
sdfb4for continuum/spectral-line projects OR -
pdfb4for pulsar observations.
5.6.2.3 Multibeam Correlator
On JOFFREY:2, in the third virtual window.
If using the Multibeam correlator, on the bottom panel, click on “Backend Tools” (three times) to open three ssh connections to pkccc1. Now type the following:
-
pkcorin the first, -
spdin the second, and -
mbtpin the third.
5.6.2.4 MoniCA
On JOFFREY:2 in the fourth virtual window.
On the bottom panel, click on “Observing Tools” and start MoniCA.
After selecting the Parkes site, you can select the appropriate monitoring GUI from the Navigator menu. Suggested monitoring items:
- Navigator -> favourites -> Generators
- Navigator -> environment -> lightning -> summary_graph
- Navigator -> pksobs -> site -> currentalerts
Note: To display multiple panels, click Window -> New window and select the page to display from there.
The currentalerts contains a watchdog monitor of a few critical systems such as UPS status and site power. It may also contain monitoring points of current interest which you should be on the lookout for. These monitoring points can change at any time and should NOT be altered unless done so by local staff.
5.7 Using VNC outside of CSIRO
If necessary, download a VNC client. We recommend TightVNC, which exists for Linux and Windows. Mac users should use Chicken of the VNC.
Establish an ssh tunnel into ATNF for VNC’s use, you will need one tunnel for each screen.
joffrey:1 => ssh your_ident@orion.atnf.csiro.au -L 5901:joffrey.atnf.csiro.au:5901
joffrey:2 => ssh your_ident@orion.atnf.csiro.au -L 5902:joffrey.atnf.csiro.au:5902
Here, your_ident is your CASS *nix account (NOT your NEXUS account). This is a requirement for remote observing.
Now, start the VNC Client on your local computer and connect to 127.0.0.1:5901, which is the VNC display for TCS, LOBOSS, etc.
Next, start another VNC Client on your local computer and connect to 127.0.0.1:5902, which is for backends such as DFB3/DFB4 and MoniCA.
If you are unable to connect using the the above AND you are outside the CSIRO network, contact your ISP or home institution.
5.8 Observing Specifics
Below is a detailed "checklist" for you to perform before you start Spectral-line and/or Continuum observations. The checklist is divided into sections, based on the application you are required to use.
5.8.1 Conversion System
- Spectral-line / Continuum Projects: To set LO attenuation, in any terminal,
enter
lorun ~/losetup/spec/pXXX.cmd("pXXX" is your project code). Check the ~/losetup directory for a full list.TBA: This can also be added to the TCS schedule file.
- Pulsar Projects: To set LO attenuation, enter
lorun ~/losetup/mb.cmdfor the 20CM Multibeam receiver, orlorun ~/losetup/psr/3100+732.cmdfor the 1050CM receiver. Check the ~/losetup/psr directory for a full list.
For both cases, to check if it attenuators are correctly set after issuing an lorun
command, press REFRESH on LOGUI. Check C12att, C30att, C40att (if using 64/128 MHz BW), and
check C50att (if using 256 MHz BW). See if these are set to the desired levels as set
in the .cmd file.
5.8.2 OPERFCC
With OPERFCC, you can move a receiver on axis. TCS should do this as long as you have the "receiver" key in your schedule file(s). If using atsnap to drive the antenna, you will need to place your receiver on focus manually by selecting your receiver and press "Place selected receiver on axis".
5.8.3 PKMC
-
Focus Cabin Switches -> Camera
TCS should do this, but on PKMC, turn off all cameras but pressing the "Camera" button to red (off). Failure to do this may cause RFI for your observations. TCS and FROG will also alert you if the cameras are still on. See the site.alarms.FCCCams point name under the Alarm Manager tab.
-
Focus Cabin Switches -> Rx
For all receivers, you should use PKMC to turn your receiver ON/OFF. Click on LNA buttons to turn them GREEN (on) or RED (off) Note: If the receiver is labeled "Local or not present" instead of "Remote", you will need to contact local staff. Also, if the System Control label is in "Local", contact local staff to place control to "Remote".
-
Switch Matrix
This is usually managed by TCS, no user action required. Some non-standard configurations require a special setup. If so directed by the support staff you will need to run an smrun script:
On JOFFREY:1, open a terminal and type
ssh glenlivet, then type-
cd SwichMatrix -
./smrun.py ~/smsetup/pXXX.cmd
"pXXX" is your project code. Note the filename may be different, check with local operations staff.
To check whether the Matrix is correctly set, you can check the connections via the Switch Matrix GUI. Some examples are shown below.
- Polarisation/spectral-line mode using only DFB3/DFB4:
- Under Pol A, your BW is connected to DFB3 A1#1 (DFB4 A1)
- Under Pol B, your BW is connected to DFB3 B1#1 (DFB4 B1)
- Pulsar observing using DFB3 and BPSR concurrently:
- Under Pol A, your BW is connected to DFB3 A1#1
- Under Pol B, your BW is connected to DFB3 B1#1
- Under MBCS, BPSR A1 is connected to channel 1 (beam 1A)
- Under MBCS, BPSR B1 is connected to channel 2 (beam 1B)
-
- Cal Control Unit
- If Tsys is to be recorded using DFB3/4 => Set the Calibration signal
- Managed by TCS with CALMODE = SYNC keyword in schedule. CALMODE = OFF disables Tsys measurements.
- Click "show" of the "Cal Control Unit"
- Turn off all cal signals
- Turn on cal signal "row of your receiver => column BEC-Sync0"
- Note: the TCS schedule command "enable becc" should also enable Tsys logging.
- This is a spectral-line / continuum option only.
- If Frequency switching with DFB3 is to be used => Set the Calibration signal (freq sw):
- Must be done manually, TCS cannot set this automatically!
- Turn on cal signal "Conv Rack Freq SW => column MBCor FreqSW"
- Turn off all undesired cal signals
- This is a spectral-line / continuum option only.
- If frequency-switching with MB20 and MBCor is to be used => Set the Calibration signal:
- Must be done manually, TCS cannot set this automatically!
- Turn on cal signal "MB FreqSW => MBCor FreqSW"
- Turn off all undesired cal signals
- This is a spectral-line / continuum option only.
- If Tsys is to be recorded using DFB3/4 => Set the Calibration signal
5.8.4 Correlator
- Spectral-line / continuum projects, check the GUI window title has "Archive: RPFITS".
- Pulsar projects, check the GUI window title has “Archive: CFITS”.
IF THE CORRELATOR DOESN’T START, follow the recommended procedures listed in the Troubleshooting section of the Correlator user Guide.
5.8.5 SPD
Some basic commands:
sel *
to see all bandpass data
sel 11
to see spectra (DFB only)
sel pp11
to see profiles (DFB only)
sel aa, bb, cc, dd
display Pol A/B, first (aa/bb) and second (cc/dd) IF
bins 1 - N
time-binning mode only: it shows the first N bins of a time-cycle (DFB only)
x
toggle "x" axis: channels <=> frequencies
a
auto scale amplitude. You can define limits, e.g. a 0 1e3
ch x-y
show only channels from #x to #y. It is usually useful to skip
first and lasts channels, e.g. ch 5-8185
avg|noavg
to enable/disable time averaging.
quit
to exit spd.
Additional commands for SPD can be found at the following: SPD Users Guide
5.8.6 MBTP
Multibeam correlator only. Some basic commands:
redraw
to redraw screen (i.e. after resizing PGPLOT window).
sel 1-13a, 1-13b
to display all beams, pols for MB20.
scale
auto scale vertical axis. You can set limits, e.g. scale 1e4 2e4
select 1 2 3 4
to show raw products 1A 1b 1B 1b (A,B: diode ON; a,b: diode OFF).
select 1-3c
to show differences A-a, B-b for beams 1-3 (both pols).
quit
to exit mbtp.
5.8.7 DATA
On any machine, data is located in directories:
- /nfs/PKCCC1_1 => MBCOR spectral-line/continuum
- /nfs/PKCCC3_1 => DFB3 pulsar
- /nfs/PKCCC3_4 => DFB3 spectral-line/continuum
- /nfs/PKCCC4_1 => DFB4 pulsar
- /nfs/PKCCC4_2 => DFB4 spectral-line/continuum
- /nfs/PKCCC4_3 => DFB4 pulsar
Note all data processing should to be done on PICTOR.
5.9 Telescope Protection System
The purpose of the Telescope Protection System (TPS) is to only capture issues that would have a major impact if not acted on in a timely manner. In the past, many of these issues have been left to the observer(s) to deal with. The TPS is a standalone controller which communicates with systems such as power, weather, vibration monitoring, cryogenics and other equipment. These devices are also connected to MoniCA, which the TPS also references.
The TPS has two forms of alert. These are "Alarm Out" and "Info Out". The TPS will follow the appropriate action as specified in Table tab:tpsactions. It should be noted that the actions described will only be carried out with the Master Control Panel in Computer Remote mode. This will become the default mode of operation for observing at Parkes.
Table 5.1: Actions that the TPS is required to take.
5.10 Weather and wind restrictions
With the introduction of the TPS, it will not longer be the responsibility of the observer to concern themselves with monitoring weather conditions, only data quality. However, observers should be aware what TPS will do in terms of protecting the antenna in terms of bad weather conditions, which are listed below.
5.10.1 Storm Park
The site.alarms.Lightning[0-4] point names under the Alarm Manager tab in FROG shows the alarms range from simply indicating (distant) lightning has been detected (priority 0-1), through to an alarm indicating you should perhaps consider parking the antenna (priority 3-4). FROG will sound an alert for priority level 2 threats or higher. The observer should acknowledge these alarms and act appropriately, or if appropriate, shelve or de-shelve if required (i.e., if there is a false alarm).
For reference, if using Monica, the lightning threat (trigger) levels are (TPS equivalents in brackets):
- No Threat (No threat)
- Some Lightning (Low threat)
- Consider Generators (Moderate threat)
- ENABLE GENERATORS (Severe threat)
- STORM PARK (Severe threat)
A lightning threat level of moderate (or greater) triggers the Generator automatic start point in Monica, causing the TPS to start the generator and run for at least 15 minutes. If after 15 minutes, the lightning threat level is less than moderate the generator will stop and power will revert to mains (if available), otherwise it will run for further 15 minutes and so on.
If the threat level is moderate and there is no generator OR the level is severe, the generator will follow the same procedure above, but the antenna will also be stowed.
5.10.2 Automated Wind Park
The SERVO computer monitors the speed and direction of the wind from the paddock sensor, and will stow the dish automatically above limits defined in tab:wind_park to ensure the safety of the antenna. Winds can be monitored with FROG.
During an automated wind park, the antenna drives to an Azimuth that has the wind at least 60-degrees away from the back of the dish without driving into an Azimuth limit. If you are observing near one of the limits and there is an easterly wind this could involve driving up to 100 or so degrees. In addition, the antenna will drive to a (software limit) Zenith angle of 1.2 degrees. Note: If the wind is particualry high, the antenna can be driven into the Zenith hardware limit past 1.2 degrees. You will need to exit the limit using the "Unstow - ExLim" button on TCS. Note the MCP must be on computer remote.
Peak Gust Average Ane #1 (Az front) 58 54 42 Ane #1 (Az front) 58 54 42 Ane #1 (Az back) 46 42 35 Ane #2 (Az front) 66 62 48 Ane #2 (Az back) 53 48 40 |
Table 5.2: Wind Park Algorithms
The Peak (2 consecutive readings), Gust (5 readings in the last 180), and Average (15 readings in the last 20) values (in km/hr) must be satisfied for a wind park to occur.
The “Az back” for each Anemometer are for winds within Azimuths 150 degrees < Az < 210 degrees (ie, winds within 30 degrees of the back of the antenna). The “Az front” values are for the remaining 300 degrees “front-on”sector.
A wind park holds the antenna at the software limit (Ze ~ 1.2 deg.) limit for 10 minutes until the countdown expires. At the end of this period the antenna is free to obey any pending or new commands.
There is also a "wind park mode" in TCS which is relevant only when using the DFBs in pulsar search mode. If enabled, TCS will attempt to complete a DFB search mode observation even if the antenna stops tracking due to a wind park, power failure, or manual override from the MCP. (This is to preserve the continuity of the time series). If the antenna becomes available before the observation has completed TCS will command it to return to the target position.
Once an automatic wind park has occurred, the antenna must not be unparked until permissible conditions have prevailed for at least 10 minutes. If conditions are poor, the antenna must be fully stowed.
5.10.3 Current Park
The wind has a greater effect on the Zenith motor currents of the dish at high Zenith angles and if it is directed either towards the surface or the back of the dish. The main problem is that a strong wind onto the back of the dish can "hold it down" causing the motor currents to reverse (the counter weight is heavier than the dish). In this case, you might receive a ’HIGH/LO Current Stow’ (as reported by SHOWTEL). In a physical sense, the low current condition is intended to detect overbalancing of the antenna when a strong wind blows into the back of the dish. The threshold for the low current condition is three occurances in 120 seconds where the difference between the Zenith motor currents is -2.5 Amp.
Once parked, you are required to wait at least 10 minutes to see if the conditions allow for observing to resume. Typically this is true if the peak wind is below 40 km/s, but it depends on the elevation of your source.
5.11 Power Supply
The Observatory has two sources of power. The principal power supply is provided from a recently installed (Dec 2012) 750kVA transformer, regulator and switchgear equipment. A 300kV diesel generator provides a backup supply to most circuits in the tower (and some elsewhere on site) in the event of mains failure. Some critical circuits have a further backup from an Uninterruptible Power Supply (UPS) which can last up to 1 hour, supplying ctitical systems. Computers, electronics, clocks, masers and receiver systems are connected to the UPS protected circuits. There is also a drive UPS, which is used to stow the antenna in the event of various triggers determined by the TPS (see tab:tpsactions).
If the Country Energy mains fail, the generator should start automatically and provide power so that after a short interruption you will be able to resume observing. If the generator fails to start and the mains supply does not return, a timer will initiate and if it reaches two (2) minutes, the TPS will automatically stow the antenna using the drive UPS.
5.11.1 Monitoring Power - Monica
You can monitor the Mains and GenSet with Monica (Monica) by clicking on Parkes - Navigator - favourites - generators. Monica should be running on the fourth virtual desktop of the VNC server, JOFFREY:1 (you can install MoniCA using the link above). A screenshot of the generators display is below.
Figure 5.3: The Parkes generator monitor page in Monica.
The likely scenarios are dealt with separately below.
5.11.2 Power failure - Brief mains glitch
In this situation, due to the drive UPS, the MCP and the Azimuth and Zenith drives will not disable. The MCP remains under computer control. If the dish is still in lock capture range of the ME the antenna will reacquire lock and the drive can resume. On the MoniCA display, you should see the following:
- LS4 - Mains power available : true
- GPC31 - Generator start enabled : false
5.11.3 Power failure - Generator starts automatically
If there is a failure of the mains for longer than a second, the generator should start automatically. Once it is up to speed it will be switched to supply the antenna. As the MCP is connected to the Drive UPS, the Azimuth and Zenith drives should still be enabled. On the Monica display display, you should see the following:
- LS4 - Mains power available : false
- GPC31 - Generator start enabled : true
If both of these items are false, proceed as described in Severe Power Failure - no mains or generator.
5.11.4 Power failure - Mains Return
When the mains power is available again, and has been stable for a period of around 1 minute, the suppy will automatically revert from generator to mains. The MCP will remain on and because the generator synchronises with the mains on transfer back to mains power, it happens without a break, so the UPS suffers no break in input power.
5.11.5 Severe Power Failure - no mains or generator
The TPS continuously checks to see if there is power, whether it be from the mains or site generator. If the TPS does not receive an acknowlegement that there is power, from the mains OR the generator, the TPS will automatically stow the antenna using the drive UPS.
5.11.6 Pre–empting an outage
If there is a need to pre–empt a main outage (Thunderstorms, planned maintenance), you can turn on the generator via the PKMC GUI.
Note: It is no longer necessary to halt observing to switch between the Mains and the generator.
On the main PKMC GUI, click "Site Generator" (under "Other"). Click either "GENERATOR" or "MAINS", depending on your requirements. Make sure the System -> Control status is set to "Remote". If it is in "Local" (as shown below in fig:pkmc_genset), contact local staff immediately.
Figure 5.4: The Parkes generator GUI in PKMC.
If the power from the generator should fail in some way, the system will automatically switch back to mains power (if available).
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