Privacy and Security Notice

FAQ Problem Reports

G0 target: Opening the JT actually closes it
G0 target: Site-wide Power Failure
G0 target: typical warmup
G0 target: typical cooldown , here too
G0 target: target scan
G0 target: Changing the alarm limit files
G0 target: Tach problems
G0 target: MedmQ
G0 target: New HPH PS pin assignments, and problem (and fix) with power calculation
G0 target: Mystery pressure drop when going to C or out-of-beam position
G0 target: ITCs hang, heater goes beserk
G0 traget: Coolant xfer line insulating vacuum
G0 target: Gas target running
G0 target: House helium leak
G0 target: xfer line IV
G0 target: No Striptool, readout errors stuck on

Any tgt: Frozen computer (eg jeffylab)? Then restart X by typing `control-alt-backspace' , then type `startx'.
Sp03 tgt: GRS notes on the cooldown procedure
SP03 tgt: GRS notes on the warmup procedure
SP03 tgt: GRS notes on the ALH files & Checklist

SP03 tgt: Can't operate JT valve
SP03 tgt: Yellow alarm handler light won't go away.
SP03 tgt: Can't start alarm handler. Can't start the stripcharts.
SP03 tgt: IOC won't reboot.
SP03 tgt: Cryostack lifter does not work.
SP03 tgt: JT PID for parking the target on autopilot:
SP03 tgt: Shorted high power heater

SM04 tgt: Archiver stopped.
SM04 tgt: Scattering chamber vacuum.
SM04 tgt:

Any tgt: Terminal Bell volume
Any tgt: Automatic Paging
Any tgt: Flatline Alarm
Any tgt: Beam Current & Raster Alarms
Any tgt: Turbopump or vacuum problems
Any tgt: Power cycle the fans

FAQs:

Archiver stuck:  Check status at http://jeffylab:4812/   Go to Groups, Target.
 To restart archiver, on jeffylab, ~/Archives,  type ./start_archiver  (that stops & starts it). There is also a ./stop_archiver, by the way.

How to print or make the Checklist: cd $GUI, ./Make_Checklist.bash
To print: rm ~/Checklist,      ./Make_Checklist.bash > ~/Checklist,       pdq -Pchchp2 ~/Checklist

Can't operate JT valve: Usually because the step size is zero. One operator had problems entering a step size because they had forgotten that you have to double-click in the step-size field, enter the step size, then hit enter all while the mouse is still in that step-size field.

Stuck alarm handler: Sometimes after an alarm, you can't clear the light in the alarm handler. Just stop and restart the alarm handler from the main gui.

Can't start alarm handler and/or stripcharts: Usually because someone killed the xterm window from which the main GUI was launched. When this happens, kill the main gui and everything else, bring up a new xterm, restart the main gui and everything else. Note that this xterminal has to stay alive in order to receive diagnostic messages. If it is dismissed, things won't work or won't start like the alarm handler and the stripcharts.

IOC won't reboot: Ususally because the network is down. In this case, closely monitor the TV temps on the ITCs and adjust the auxillary heat load pots by hand to keep the temperatures near their goal values. Retry the IOC reboot every 5 or 10 minutes until the network is back and the reboot succeeds. Can also be the optilogic box behind the furthest left blue racks in the electronics room. Go thru the startrek doors, turn left, walk to the wall. Go behind the racks. In the middle rack, about chest high, is some black box with the word optilogic on it. Pull the power cable to power cycle it and you ought to be back in business.

Cryostack lifter doesn't work: Usually this is because someone has pressed (accidentally) one of the several emergency buttons which kill the power to the lifter. See for example this hclog entry.

 JT PID: This JT pid was tried out over the 2003 open house. It adjusts one of the JTs to keep the return temperature at 30K. This way the targets can all be left safely as gas, not liquid. The pid parameters are given in hclog 60105.

Shorted HPH: Symptoms of the short we had in the HPH can be found in hclog entries 58828 , 58857 ,

Changing default alarm limits: In /group/gzero/g0targ/bin/alarmlim-cold-H2.csh, edit the caputs to reflect the new alarm limits you want to overide the existing defaults. As g0targ@gzerol2.acc.jlab.org.

Tach Problems: In the main gui "general" button, under "tachometer expert". After a power cycle it may come back in local instead of remote mode. You can reset it from this GUI.

Or, you can filter out the noise that is there on the readout sometimes. Note that an IOC reboot can sometimes reduce the noise. But if it persists, the options are:

The smoothing factor is a configurable value between 0 and 1 were 0 means no smoothing and 1 is ultimate smoothing (in fact, the data value will never change)..default will be .95

After a reboot, sometimes the tach readback is so noisy even the filtering is useless. Another reboot will solve this problem. Don't ask me why, but this ALWAYS works!

:MedmQ Starts the main G0 target GUI without all the strip charts and without the alarm handler. Useful when running/monitoring from home, for example.

New G0 HPH PS: The current reaback is flakey. So new variables ghptrue_ca and ghtot_ca were made based on V^2/R instead of V*I. But the main GUI still shows ghptrue and ghtot based on V*I for now, because it is hoped the curr3ent readback problem can be fixed in May.

Terminal Bell Volume: From an xterm on the target computer, use the xset command:
To set bell volume, pitch and duration:
         xset b [vol [pitch [dur]]]          b on

b       The  b  option  controls bell volume, pitch and duration.  This
               option accepts up to three numerical  parameters,  a  preceding
               dash(-),  or  a  'on/off' flag.  If no parameters are given, or
               the 'on' flag is used, the system defaults will  be  used.   If
               the  dash  or 'off' are given, the bell will be turned off.  If
               only one numerical parameter is given, the bell volume will  be
               set  to  that value, as a percentage of its maximum.  Likewise,
               the second numerical parameter specifies  the  bell  pitch,  in
               hertz, and the third numerical parameter specifies the duration
               in milliseconds.  Note that not all hardware can vary the  bell
               characteristics.   The X server will set the characteristics of
               the bell as closely as it can to the user's specifications.

Transfer Line IV: Look at this link. It describes usual vacuum (a few mTorr) for the 15/20K coolant lines from the C-can to the target.

GUI_Cleanup: We had a weird error. Stipcharts would not come up after a reboot. There were white alarms on everything that were latched on but which were neither active nor clearable. But everthing was being read out just fine. Solution was to kill -9 all processes listed by the "ps -a" command.

Saw made a script called "gui_cleanup" that should kill all medm, StripTool and alh processes running under the g0targ account.  It should be enough to type "gui_cleanup".  The script is in /group/gzero/g0targ/bin which is in the path.

Automatic Paging :
April 25, 2003

Steve has successfully set up the alarm paging system.
To turn it on, as cvxwrks@jeffylab goto /home/cvxwrks/PAGER and type
./enable_target_paging. Likewise, to disable it type
./disable_target_paging. These little scripts are:

more ./enable_target_paging
     #!/bin/sh
     cd ~/PAGER/oncall_pager
     cp targetdaq.alhConfig pager.alhConfig
     killall alh.new

So the enabler copies the file you edit (targetdaq.alhConfig) into the
file that is looked at by the alarm handler (pager.alhConfig). Make
any changes in alarms, etc. to targetdaq.alhConfig (not to
pager.alhConfig). Or set up new scripts with different alarm limits
(for parking, for example) and cp them into pager.alhConfig.

This file consists of entries like this:
CHANNEL TARGET hcITC502_3_Sensor_1_R
$ALARMCOUNTFILTER 999999999 10
$STATCOMMAND HIHI pageOnCall.pl -target -grp "TARGET" -sig "hcITC502_3_Sensor_1_R" -m "hcITC502_
3_Sensor_1_R HIHI"
$STATCOMMAND LOLO pageOnCall.pl -target -grp "TARGET" -sig "hcITC502_3_Sensor_1_R" -m "hcITC502_
3_Sensor_1_R LOLO"

The 10 on the second line says the alarm condition has to have been on
for 10 seconds in order to generate a page. The actual alarm limit
value is that already in the IOC, defined by the loaded
alarmlimits.bash file in
/u/group/poltar/ctarg/Screens/ALH/alarmlimits.bash.

The kill command kills the pager alarm handler. It is restarted
automatically by cron. To see that it's in the cron table do a
crontab -l.

Phone numbers for paging are defined in /home/cvxwrks/PAGER/oncall_pager/pageOnCall.pl

Flatline Alarm:
Steve W. set up a nice alarm that goes off if the temps have flatlined for 10 successive reads. It runs on cdaql5 under cvxwrks in the file checkbeamAndHVAndTarg.bash in ~/users/willy. See hclog 126947.

In spring 2008 we modified this and put it in a cron job. See hclog  155145.

Beamcurrent and Raster Alarms:
There is now a GUI which assigns the maximum beam current for each target we have. The same GUI also allows you to specify whether the raster has to be on or not for each target. This GUI can be found at /group/poltar/ctarg/Screens/BDS_maxcurr.adl and you open it from medm. You can type in the desired beam current maximum for each target. Enter a raster value of 1000 for those targets you want the raster to be on for. And a zero for those targets you don't require a raster for. This GUI is only used to generate alarms through our EPICS alarm handler in the counting house. It doesn't make an FSD or anything like that, just a beep in the counting house. The alarms themselves in the alarm handler are hcMaxBcmCurrentAlarm and hcRasterMaskAlarm. These are logical values, they are 0 when the respective test is OK, and 1 when the test has failed (ie when the beam current is higher than specified in the BDS_maxcurr.adl table for the target currently in the beam).

The values used in BDS_maxcurr.adl during spring 2008 are shown here.

To reload all these limits along with all the other alarm limits, click on the "alarm handler" button in the main GUI, then choose the option "Reload Alarm Limits". This will load all the values in the file Gep07.alarms in the /Screens directory.

Turbopump:
The normal vacuum in the scattering chamber is in the 10^-7 Torr range when the target is cold and cryopumping. The gate valve interlock which closes the gate valves on both sides of the SC is set to 5 x 10^-5 Torr- we obviously have to stay well below this pressure. We don't start a cooldown of the target unless we are well into the 10^-6 range (with the target warm).

If you suspect the scattering chamber turbopump has tripped off, then you have to go into the hall to check. The turbo controller for the turbo on the scattering chamber is located in a blue rack, just behind the target gas panel, behind the right side of the gas panel. You can't miss it, it's about face height, a black box with a bunch of white stripes running diagonally along the front panel. Normally, the green power and normal lights are on.There should only be one or two of the lowest of the diagonal leds lit, indicating the load is light. If the "failure" light is lit you have to restart it. Press stop, then start. If that doesn't work, power cycle it and then turn it on and press start. The load will run up to the top of the diagonal stripes, then back down over a couple minutes as the turbopump spins up. The manual is here (second half is in English).

It can be that the gate valve between the turbo and the scattering chamber has closed. That valve control is on the 1st floor of the blue platform (right above your head if you are standing in front of the turbocontroller) about halfway along the long side closest to the HMS. Just to the left of the 4He panel. The turbo's backing pump is located right there as well.

There are two cold cathode gauges right next to the turbocontroller. One reads the vacuum in the girder just upstream of the target. The other reads the vacuum in the scattering chamber itself.

Power cycling the Fans:
Before you power cycle the fans, you should try to restart the fan from the GUI. It's finnicky. Try to clear, reset, off and on. Try it several times. Wait a few seconds between operations. Try a few permutations on the buttons. Try starting it at 30 Hz (12%) instead of 60 Hz (25%). Try rebooting the IOC and then retrying to start from the GUI.

If none of that works, then you will have to power cycle the fans. First, note the status lights in ALL 3 fan controller GUIs. Having that info in hclog will help us diagnose the proble later on and should be useful in devising methods to improve reliability of the fan controllers. Then ask MCC for an ARM, escorted access. Do not wait for a sweep, you need to get the fans back on asap.

Go into Hall C with the ARM. As soon as you're in the hall, turn right and walk to the row of blue racks just upstream of the green shielding wall (where the SOS power supplies are). At the nearest end of those blue racks are some cotton coats that look like they just were delivered by the dry cleaners. Put one on, this is your PPE for this activity. There should be safety glasses in the vest pocket. Put those on too. Then walk to almost the end of the racks. In the blue rack that contains the 3 fan controllers and the three tachs (waist height) you will find the circuit breaker for the fans. It is mounted on the side of that rack and it's best to access it from behind the rack. It's on the right side of the rack, about chest high, and is the size of a couple of shoe boxes. It's grey with a big handle on it. Throw the switch on this 480 V circuit breaker off. Wait 30 seconds, Then turn it back on. Then try to restart the fan from the GUI.