Preliminary Version
FTPC procedures for Y2007
This procedure manual is updated whenever the procedures change.
Consult the "FTPC detector operator home page" for the very latest information.
(http://orion.star.bnl.gov/public/ftpc/operator.html)
Date of last update: March 27, 2007
Janet Seyboth - MPI
Terry Tarnowsky - Purdue
PLEASE READ BEFORE OPERATING THE FTPC.
FTPC procedures for Y2006 html
FTPC procedures for Y2005 html
FTPC procedures for Y2005 in MS-Word format for printing DOC
FTPC procedures for Y2004 html
FTPC procedures for Y2003 html
FTPC procedures for Y2001 html
To Access the 2007 FTPC Electronic ShiftLog:
Go to FTPC Detector Operator homepage.
Select link for "Run Operations".
Under "Shift and Run Records" select "Electronic ShiftLog 2007".
Select "Start the editor".
Choose "FTPC" from the list of subsystems.
Make ShiftLog entry.
General introduction
The STAR FTPC (Forward Time Projection Chamber) is a
cylindrical TPC with radial drift using an Ar-CO2 50%-50% gas mixture.
Oxygen content in the gas has to be kept strictly below 10 ppm to avoid
a significant absorption of the charge of the electron clouds during their
drift to the anodes.
The drift field is generated by the HV electrode (cathode) at the
inner radius of the cylinder and terminated by the field cages at the cylinder's
ends.
A potential of -10 kV is applied to the cathode and distributed to the field
cages in order to generate such a field.
The signals are generated by the collection of the charge induced by the
drifting electron clouds, formed by the passage of charged particles in
the gas, at the anodes located at the outer radius of the cylinder.
The amplification stage is accomplished by sense wires in proximity to
the anodes, kept at a typical voltage of +1800V.
A gating grid is also placed in proximity to the anodes, to avoid charge
accumulation in the drift region. The typical potential of the open gate
is -76V.
Two such detectors are installed in STAR, covering the -4 < η < -2.5
(east) and 2.5 < η < 4 (west) pseudorapidity windows.
In summary, the two detectors are operated by the following apparatus:
- gas system (Ar-CO2 50%-50%, O2 < 10 ppm);
- cooling system (to cool down the
electronics)
- field cage (cathode) power supply
(-10kV, 1 channel/ detector, Heinzinger);
- anode sense wires (anodes) power
supply (+1800V, 6 channels/detector, Le Croy);
- gating grid power supply (-76V open,
4 channels/ detector, UCLA);
- electronic power supplies (10 units/detector,
LBL).
The STAR-FTPC detector can be fully operated by remote
control at the FTPC
console (cassini.starp) in the STAR control room. The exception is the gas
system located in the gas mixing room.
The FTPC is based on the EPICS infrastructure, as the other STAR control
systems. It is a complex and delicate system, interfacing with many different
hardware parts. Sometime it may seem slow, but the emphasis had to be put
on safety of operation. The obvious general recommendation is therefore
to be patient and mindful when operating the
control system.
Once you are at the FTPC console you should see the
FTPC control and monitor systems main page (main control window):
Figure 1: The Main Control window.
If this image is not on the screen you should verify that you have
an open window on the slow control state machine (sc3.starp.bnl.gov).
The sc3 username (sysuser) and password should be known by your shift
leader. If not, contact a member of the FTPC or the Slow Control group. To start the FTPC control and monitor system just type
"ftpc" on the sc3.starp.bnl.gov window.
-
If the "main control window" still does not appear, somebody else is using
it. Please, check who else is working on the FTPC Slow Control. You can
always force the window by deleting the FTPC lock-file from the sc3.starp.bnl.gov window:
cd epics/R3.12.2-LBL.4/FTPCtopApp
rm /star/sc/users/sysuser/epics/R3.12.2-LBL.4/FTPCtopApp/ftpc_lock
Preliminary checks
At the beginning of each shift the detector operator
should check the FTPC
operator home page (STAR home -> Experiment -> Subsystems -> FTPC -> Detector
operator home page) and should go through a series of checks (a checklist
will be made available by FTPC people on the web), to ascertain that all
parts of the system are in a proper state and ready to operate. If this
is not the case the operator should take action where possible or call the
FTPC experts immediately and alert the shift leader.
Interlock status
Next the interlock status should be checked. The status
of the interlocks affecting the FTPC is shown on the main control window.
A green light signifies that the interlock is giving permission for operation.
If one or more interlocks failed (red light on) the detector cannot be
operated.
-
The "Electronic permissive" and the "Detector leak" entries in our interlock
frame reflect the status of the STAR General Interlock System (SGIS). In
case one of these interlocks failed (red light on) nothing can be done
by an FTPC operator, but the shift leader should be notified in case he/she
is not yet aware of the situation.
-
If the "HV permissive from gas" interlock fails (red light) you should
immediately notify one of the FTPC experts and the shift leader. In this
case all the high voltages of the FTPCs are turned off automatically and
the detector is not operational.
-
If the "LV permissive from cooling" interlock fails (red light) you should
make sure that the cooling system and its circulation pump switches are
set to their "On" status. After turning on the cooling system wait for
the interlock to clear (it takes few seconds). If the "LV permissive from
cooling" interlock is still triggered (red light) cycle the power on the
cooling system once more. If the interlock condition persists, alert
one of the FTPC experts immediately and notify the shift leader
Cooling system
The cooling system is controlled by the "Cooling System" frame on the main
control window.
It is a leak less system maintained below atmospheric pressure. It uses the
modified chilled water (MCW) supply to cool the FTPC cooling water in a
secondary circuit.
Monitoring relevant quantities
Relevant quantities can be monitored by selecting the
appropriate monitor window from the "Monitor" scroll down menu in the main
control window (Figure 1). Detailed information is given in the following
windows:
- Gas;
- Temperatures and Pressures;
- Readout Board Voltages;
- Anode Voltages and Currents;
- Experimental Hall Temperature and Humidity;
- Summary.
-
The "Summary" window should
ALWAYS accompany the main control window on the computer screen.
To open this window, go to the
"Monitor" --> and click on "Summary" option.
Figure 2: The "Summary" window in a typical "Physics" configuration.
In this window are shown the anode sense wire (anodes)
measured voltages and currents, the HV electrode (cathode) measured voltages
and currents, the pressures and temperatures of the cooling water, the
gas temperature at the detectors, the gas flow and the O2 content, the gating grid voltages, and the temperature and humidity in the experimental
hall.
In the top left corner of the window is shown the status of the several parts of the detector. As a general rule numbers are presented in colors:
yellow signifies a low severity alarm, red a high severity alarm and green
the normal range of operation. A number in black color means that that
specific parameter is not yet connected to an alarm condition.
The update of the values in the monitor windows takes few seconds. Also,
some variables update faster than others.
Configuration
Normally the detector should stay "ON", and the detector
operator only has to change its "configuration". The detector can be configured
for Physics, Laser, Pedestal, Stand by, or Magnet ramp
modes. The only difference between these configurations is the voltage
of the anodes and the status (on/off) of the FEEs and the readout boards.
When the detector is turned on the cathode and the gating grid voltages
are on in every configuration.
To achieve the proper configuration select it from
the scroll down menu on the left side of the main control window
and then press the configure button. If the detector is ''ON'' the
anode voltage will ramp to the proper value, otherwise the voltage set point
will be stored and be ready to be loaded as soon as the anode voltages
are turned on.
-
The low voltage power supplies are always on, unless the detector
is configured in "magnet ramp" mode.
-
After the magnet ramp is completed
the detector operator should change the configuration
to "Stand by'' or to any pertinent value, but not leave it in
the "Magnet ramp" mode. In this way the electronic will be turned on, temperatures
and pressures will be readable and the detector will stabilize its temperature.
-
During RHIC filling and dumping or during short shut downs the detector
should be configured in "stand by" mode.
Turning off the detector
This operation should be performed only when a long
shut down of RHIC is foreseen (> 1 shift) or a possible danger to the detector
is foreseen but is not immediate: an incoming thunderstorm associated with
RHIC turning off, possibility of beam hitting the detector, before a system
reboot if possible, or any other dangerous situation communicated by the
shift leader or the main control room (read the "Emergency shut down" paragraph
for procedures in case of an immediate danger).
Has to be emphasized that the standard status of
the detector is "ON".
-
Also, the cooling system should always be left ON
-
The easy and preferred way to turn off the detector is to press the "OFF"
button in the "Turn on/off" frame in the main control window. The operator
should then observe the voltages to go to zero from the summary window
and the messages scrolling on the main control window message frame to
ascertain that the turn off process is being accomplished properly. The
turn off process takes about 2-3 minutes. When the detector is turned off
water pressures and temperatures are not readable and are set to zero.
-
Another way to turn off the detector is to access the "Quick on/off" window
through the "Control" scroll down menu on the main control window. From
this window all the FTPC subsystems can be switched on/off separately.
Figure 3: The "Quick on/off" window.
-
For this second method (Quick on/off) the order in
which systems should be switched off is indicated by the direction of the
red arrow, beginning at the bottom and proceeding upward. It is important
to follow this order to avoid subjecting more delicate parts to unnecessary
stress by the induced currents in the turn off process. When using this
method to turn off the detector care should be taken to ascertain that,
for each subsystem, the operation is completed before switching the next.
-
As a third option to turn off the detector all channels of all subsystems
can be switched off separately by selecting the proper control window from
the "Control" menu in the main control window. This option should
be generally left to the detector experts.
Emergency shut down
The emergency shut down is NOT a healthy procedure for
the detector, and should be avoided whenever is possible.
To perform an emergency shut down press the corresponding button on the
main control window. The following window will appear:
Figure 4a: The emergency shut down confirmation window.
The main control window will disappear. To shut down press the "Yes"
button. To go back to the main control window press the "Go-back" button.
During this process the windows might get the wrong color map. To restore
the proper colors they have to be slightly dragged. Situations that may
require an emergency shut down include a sudden increase significantly
beyond the standard operating range (alarms off and beeping) of all or
most of the anode and/or cathode currents of the detectors.
Once the emergency shut down procedure has started all voltages will be
zero within few seconds, and afterwards the control program will set all
operating parameters to the standard "Off" status.
If the emergency shut down was required by a specific FTPC problem,
or when in doubt, notify immediately, by phone or in person, the
FTPC experts, otherwise just send them an e-mail.
If an emergency shut down is performed, an FTPC expert must be notified following the incident.
Turning on the detector
-
Make sure that the STAR magnet is not ramping!
-
Similarly to the turn off procedure this action can be performed through
a single button operation (which is the preferred way to do it), pressing
the "ON" button from the "Turn on/off" frame in the main control window.
This procedure takes about 3-5 minutes to complete. After completion the
detector will be in the state defined in the "Configuration" menu.
-
The other option is to open the "Quick on/off" window (Figure 3) from the
"Control" scroll down menu in the main control window and to proceed turning
on the subsystems along the green (ON) line. In this case care has to be
taken to insure that one action is completed before stepping to the next.
When going through this procedure using the "Quick on/off" panel the detector
configuration is overwritten and all components will be turned on.
-
All channels of all subsystem can also be switched on individually by selecting
the appropriate control window from the "Control" scroll down menu in the
main control window. However this is an option that should be left to the
detector experts. During the turn on procedure the operator should observe
carefully the message frame in the main control window and the monitor
summary window to verify that the procedure is being executed properly.
Computer system
The control system makes use of 4 computers:
- the MVME 167 control processor in
the FTPC VME crate (#71) on the south platform;
- the slow control state machine (sc3.starp.bnl.gov)
- the FTPC WINDOW NT PC (bond.starp.bnl.gov)
in the gas mixing room at the FTPC gas rack;
- the FTPC control console (cassini.starp.bnl.gov).
The MVME 167 is the processor where all the control
and monitoring tasks are running. It sends all the parameter information
to a parameter database that is managed by the slow control state machine.
Data coming from the gas system are read out by the FTPC WINDOW NT PC and
delivered to the MVME 167 through the online computer. They are then processed
by the MVMe 167 and the parameters are sent back to the parameters database
on the slow control state machine.
Finally the Graphical User Interface of the control software is run on
the slow control state machine from the FTPC control console.
Rebooting
The possibility of a computer crash cannot be excluded
a priori. If the MVME 167 CPU crashes all parameter fields depending on
it will be shown in white color on the graphical interface.
Figure 4: The main control window after a crash of the MVME167 processor.
In this case a reboot of the MVME 167 is urged. From the main control window
press the "Reboot" button. The following window will appear:
Figure 4a: The reboot confirmation window.
The main control window will disappear. To reboot press the ''Yes''
button. To go back to the main control window press the ''Go-back'' button.
During this process the windows might get the wrong color map. To restore
the proper colors they have to be slightly dragged. If a window with
the following message appears:
Mon Jun 18 13:51:00 EDT 2001
medmCAExceptionHandlerCb:
channel name: cu_vme71_control_boB2
message: Could not perform a database value
put for that channel
... ignore it, close it and try the "Reboot" button again until the
window does not appear anymore (although often it works straight away
at times it may need five or more attempts). At this point the operator
can be sure that the reboot is actually occurring. It takes about 3 minutes,
but it might take more, depending on the traffic on the network. Another
method to reboot the MVME 167 is to enter the "VME STATUS" screen which
can be opened from the main control window:
Figure 4: VME status window.
and to turn the VME crate off (wait for the voltage indicators to go to
zero), wait a few instants and then turn it on again.
-
The reboot is not an ordinary operation, and the FTPC experts should be
notified by e-mail of any reboot.
-
After the reboot the system should be brought again to its original (on
or off) state by operating the standard "turn on" or "turn off" procedure.
This is only to make sure that all the parameters are in the proper settings
for the present running conditions and were not altered by the reboot process.
-
If the FTPC console (cassini.starp.bnl.gov) crashes it can be rebooted
in the standard way. The operator will then have to log in again using
the username (operator) and password written on the computer.
-
If the gas parameters are not updated the status of the FTPC computer in
the gas room should be checked. If it has crashed it should be rebooted.
The operator should then log in using the username and password written
on the computer. During the login the password for the cross mounting
of the /online disk will be asked for. This will be found on the computer
too.
Alarm handler
The alarm handler alerts the operator when a sensitive
parameter goes out of the range of standard operation. A visual and an
audible signal are released in this case. The detector operator should
click on the alarm handler miniature window (Figure 5),
Figure 5: The alarm handler miniature window.
to open the main alarm handler window (Figure 6).
Figure 6: The main alarm handler window.
From this window, by pressing the uppermost left square,
the alarm is acknowledged and silenced. The colored squares indicate the
parameter in an alarm state. The color red stands for a high level alarm,
yellow for a low level alarm, and white for the loss of communication. By
pressing the square with the "G" some guidance is given.
When turning off the low voltages, or turning on the anode voltage, a transient alarm might go off. This will result in one or two beeps maximum and
does not need to be acknowledged. The reason is that switching on/off devices may cause their current to deviate slightly above the alarm threshold.
If the Alarm Handler (Figure 5) is closed by mistake, all windows including "medm" should be closed and the FTPC control program restarted following the same procedure as mentioned earlier.
Known problems
-
FEEs and Temperatures
-
Magnet ramps
In case of a magnet ramp it is necessary to turn
off the FEEs (default in the Magnet ramp configuration). In this mode we
lose the FTPC temperature information.
When the magnet ramp is finished and the
FEEs are on again, there is a non-negligible possibility that the temperature
information does not come up in the East detector. This information
is VERY IMPORTANT for our physics results.
Please check that the temperature sensors are working by clicking on the
"Monitor" button in the "main control window" (Figure 1). Then select the
"Pressure and temperature" option from the pop-up menu. The "Temperature-Pressure"
window (Figure 8) will appear. Normally the temperature readings should be in the 20s. Some of the
readings will be lower than 10. This is due to a known RDOB problem (see below).
In case ALL COOLING PLATE AND BODY TEMPERATURE values for FTPC East are 0.000, the only solution currently possible
is to try to reboot the ftpc slow control. with the "Reboot" button
in the "main control window" (see chapter about rebooting procedure). This process
will take 5-10 minutes and during this time the connection will be off and
there will be no parameter values. After that, the detector should be on
again. The rebooting is not a normal procedure so, please, consult an
FTPC expert first.
Additional sensors seen in rows at the bottom of Figure 8 will always display temperatures, even when the FTPC FEEs are off. These are from an independent system.
Temperature 7 in FTPC W does not exist and will always display "0.000".
-
Broken sensors
The "Output gas" thermistor on the west chamber is broken. The display always shows 0.0 in white color.
The alarm handler is already set to ignore this broken sensor. Corrected for 2005.
Figure 8: The Temperature and Pressure monitoring window.
Anode problems
-
In the case that one or more of the anode HV channels
trip, the operator should first clear the trip. To
do this, open the "Anode voltage" window (Figure 7) by clicking on
the "Control" button in the main control window (Figure 1). The channel that
has tripped will be marked by a red flag, while all the others should
be marked green. Please make a note in the FTPC log book (and/or Electronic ShiftLog) as to which channel tripped.
To clear the trip just press the "CLEAR" button in the bottom left corner
of the window. After a short time the tripped channel(s) should be marked
with a brown flag (disabled channel). To restore the voltage press the
"ON" button on the anode voltage switch in the "Quick on/off" window (Figure 3).
If the trip happens once more on the same channel(s) the operator should
call
a detector expert.
-
Changing the configuration from physics to laser, sometimes the
anodes voltages in the West chamber do not go up to the nominal value (1200
V). This value should be forced from the "Control"-->"Anodes" window.
Figure 7: The anodes control window.
RDOB problems
The "RDOB Voltages" display may show values which are either too high, too low or equal to 0.0
This is due to known problems in the electronics which can only be repaired when the FTPC's are taken out after the run.
Standard set points
|
Cathode voltage (2 channels) |
-10kV±5V |
Anode voltage (2x6 channels), Physics |
+1765V±2V West, +1750V±2V East |
Anode voltage (2x6 channels), laser |
+1200V±2V West, +1200V±2V East |
Anode voltage (2x6 channels), pedestals |
+1000V±2V West, +1000V±2V East |
Anode voltage (2x6 channels), stand by |
0V West/East, (+~15V are displayed) |
Gating grid (2x4 channels) |
-76V±2V open, -76V±115V closed |
|
|
|
|
|
Standard values
|
Water pressure in (West/East) |
-400mbar -> -100mbar |
Water temperature (West/East) |
<31 C |
|
|
O2(ppm) (West/East) |
<10ppm |
H2O (dp C) (West/East) |
<-50 C dp |
Ar flow = CO2 flow (West/East) |
72 l/h->78 l/h;West=East |
|
|
Cathode current |
0.14mA |
Anode current |
-15nA < I < 15nA |
Created: Wed Jun 13 14:25:19 EDT 2001 by Gaspare Lo Curto
Revised for Y2003: Jan 1, 2003 by Maria Mora
Last modified: Mar 27 18:00:00 GMT 2007 by Terry Tarnowsky