1. A status report on the HMPID DCS
The HMPID in ALICE ;
The HMPID Detector Control System: Hardware and Software Architecture;
Investigated solutions for the HV-LV power supplies and market survey;
Overview on the components of the HMPID Control system:
The (CAEN SY1527) HV C.S. in the PVSS environment;
A custom C.S. for the EUTRON LV units;
A C.S. prototype for the Liquid re-circulation apparatus;
Next steps………...
Expectation from the JCOP and CCTeam

2. HMPID layout on the Spaceframe
The ALICE Particle Identification system (PID) is based on three detectors covering the central ALICE barrel (ITS, TPC and TOF), and one single-arm detector: the High-Momentum Particle IDentification (HMPID).
The HMPID is based on a Ring Imaging Cherenkov dertector, it is devoted to the identification of the high-momentum pions, kaons and protons in the range GeV/c.

3. RICH detector: basic elements
The RICH detector consists of a vessel containing C6F14 as liquid radiator and a multiwire proportional chamber with a CsI segmented photo-cathode. When a relativistic charged particle cross the radiator faster then the phase velocity of light in that media, then few tens of Cherenkov photons are emitted and converted on the CsI film.
The emission angle of photons is related to the particle velocity v according to
cosq = 1/nb where b=v/c.
If the particle momentum is known then its identification can be done, with this detector layout, in the range 1-4 GeV/c 3

4. An artistic view of the hardware!
Basic elements of the
HMPID DCS
An artistic view of the hardware!
Supervisory Layer
NT Workstation
Control & Physical layer
CAEN SY1527
PLC S7
PLC S7
PLC S7 ??
Low Voltage Sub-system
Gas
Sub-system
High Voltage
Physical parameters
Cherenkov liquid radiator

5. The Software Architecture of the HMPID DCS
LPC = Local Process Control
HMI = Human Machine Interface
FSM = Finite State Machine
DIM = Distributed Information Manager (CERN)
SMI = State Management Interface (CERN)
OPC = OLE for Process Control (Microsoft)
DCOM = Distributed Component Object Model (Microsoft)

6. Working in Progress on…..
Evaluation of a preliminary asset of Data Point for the HV Sub-System (the physical device SY1527 is not yet available in the present framework
This OPC serv. doesn’t run properly in PVSS and it doesn’t allow the grouping managment! CAEN will issue the version 1.1 on Aug
Some Detector Oriented panels in PVSS for Monitoring and Setting are already under test
Perfectly working !
Preliminary representation of the LCS via GRAFCET. The related Instruction List is already in Debugging Phase
Preliminary GRAFCET and Instruction List in Test Phase

7. Operational classes of the HMPID DCS prototype
(Preliminary definition)
CONFIGURATION
MONITORING
OPERATIVE STATUS
DEBUGGING
checks the Permission Access Policy
provides Panels to Load, Edit and Save Sub-Detector Configuration Parameters
verifies the selected detector Configuration
Logging of the selected Configurations
provides Panels to display/modify Actual/Trend/Historical Parameters
verifies that the Parameters are in the ranges
provides Alarms management
provides Logbook facilities
accept commands from the supervisory layer
check the Permission Action Policy
control and synchronise the sequence of operations
provides Local Process Control procedures
provides tools and facilities for Sub-Detector debugging:
dummy Trigger equipment,
local data taking,
data base management, …

8. Investigated solutions and market survey for the HV-LV sub-systems

9. Power requirements/segment
LV-HV Sub-systems CAEN solution: Resulting detector segmentation
12 MCM Segments
4 ADC Segment
9 FEE Segments, 180 (120) GASSIPLEX each
9 HV Segments, 36 (24) wires each, this requires a grouping of 12 sense wires
FEE 1
FEE 2
FEE 3
FEE 4
FEE 5 6
FEE 7
FEE 8 9
MCM1
MCM2
MCM3
MCM4
MCM5
MCM6
MCM7
MCM8
MCM9
MCM10
MCM11
MCM12
ADC1
ADC2
ADC3
ADC4 H1 H2 H3 H4 H5 H6 H7 H8 H9
Power requirements/segment
V A W
FEE (3.2) 13.5 (9.0)
FEE (3.4) 14.0 (9.5)
ADC
ADC
MCM
7 x HMPID MODULE
3 x CAEN SY1527 (TCP/IP protocol)
Boards:
9 x A1517 3V-6A (prot. by the end of 6/2001)
11 x A1518 5V-3.6A(.. by the end of6/2001)
6 x A1821A 3kV (Delivered and test under way)

10. Layout of the CAEN solution
Rear view
Front view

11. Power requirements for each segment
LV-HV Sub-systems WIENER or EUTRON based solution: assumed detector segmentation
MCM1
MCM2
ADC1a
ADC1b
FEE 1
FEE 2
FEE 3
FEE 4
FEE 5
FEE 6 H1 H2 H3 H4 H5 H6
2 MCM Segments
1 ADC Segment
6 FEE Segments, 480 GASS. each
6 HV Segments, 48 wires each
Power requirements for each segment
V A W FEE
FEE
ADCa+b
ADCa+b
MCM
For both these solutions, the HV PS is still based on the CAEN SY1527

12. Layout of the WIENER LV units
The Master Power Box can operate via
RS232 up 8 slave crates
CANbus up to 127 crate
TCP/IP offers performance for larger numbers of channels.
Master Power Box
Master power 3U box:
Max DC Power/box =2.5 KW
Up to 12 PL600 modules/box
One module consist of one floating ch.
2..7V - 25A max 175W
FEE : 42 segments x 2 polarity
 84 modules (2.8Vx12.7A=36.5W)
MCM : 14 segment
 14 modules (+5Vx18A=90W)
ADC : 7 segments x 2 polarity
 14 modules ( 5Vx16A=80W)

13. Layout of EUTRON-PLC devices
For the EUTRON solution the power switching and sensing of each LV channel are based on a Siemens PLC system (relays and ADC modules) and a custom sensing board. This solution requires a control program developed ad hoc by the user.
EUTRON PS Units
PLC SIEMENS S7300
Connecting and sensing Board
TO HMPID MODULES
3 x EUTRON BVD 720S 0..8 v 25 A
1 x EUTRON BVD 1500S 0..8 v 50 A

14. First cost estimation (cables and connectors not included)
LV HV
€ CHF € CHF
CAEN HV-LV
EUTRON LV + CAEN HV
(PLC software development not included)
WIENER+ CAEN HV

15. The EUTRON-PLC Control System
Requirements list;
The control system as a Finite State Machine; (bubble chart)
Apparatus layout and technical specifications of the sensing board;
the PLC readout software.
E. Carrone,

16. The Requirements list
It is intended to specify all the procedures to operate properly the LV power supply units while connected to the FE electronics. An incomplete example could be:
FEE LV switching ON: since the FEE requires ±2.8 V then both these polarities must be supplied contemporary,
FEE LV switching OFF: before a FEE segments is switched OFF, the facing HV segment (see St.Rep3 at must be switched OFF. This sequence is mandatory to prevent FEE breakdowns due to charge accumulation on the MWPC cathode pads. (In fact the ground reference to the MWPC sense wires is ensured trough the FE electronics, then the low voltage at the corresponding FE electronics segment must be applied before the HV segment is switched ON);
Current and voltage ranges: Vload Iload must be in the admissible range: Vmin < Vload < Vmax, Imin < Iload < Imax. If Iload > Imax then the corresponding HV-LV segments must be automatically switched OFF according to FEE LV switching OFF sequence
Alarms handling … …
E. Carrone,

17. as a Finite State Machine:
The control system
as a Finite State Machine:
state definition
Taking into account the requirement list and how to properly operates the EUTRON units, the following “states” have been defined:
OFF ( P.S. in Standby, relays OFF and Vout=0)
Calibration (reading Voutput from units)
Configuration (FEE segment selection)
Standby (LV system in STBY status)
ON (Ready For Physics: P.S. STBY removed, check of Current/Voltage values)
E. Carrone,

18. LV: the bubble chart representation
LV C.S. representation
COMMANDS
START
RUN
FILL
PURGE
STOP
MAN
RESET
CALIBRATE
CONFIGURE
SUSPEND
FEED
CONF
STBY ON
CAL
OFF
ALARM
Alarm
Condition
STATES
CALibration
CONFiguration
STBY Standby
ON Ready
When the ON state is active Iload and Vload are monitored on all the active FEE segments. If one of these values is out of range then the relevant FEE segment is switched OFF and the HV system is contemporary notified to switch OFF the corresponding HV segment.
During the transition ON->STBY the HV status must be checked and if it is HV-ON then the LV C.S. must kill the HV system.
STATES
OFF
Stop
Running
Filling
Ready
LV: the bubble chart representation
E. Carrone,

19. Apparatus Layout
In order to split the PS current into several channels, each one connected to one FFE segment, a PLC relays module is used. The Vload-Iload measurement is based on a sensing board read out via 8CH ADC module.
Dummy resistive Load
Power Supply
Siemens
S300 PLC
Ethernet NT
Workstation
Vload sensing
line
Power line
CH1/2
Iload
sensing line
Set and reading PS Vout
from-to
PLC relays
Sensing
Board
Power Supply:
EUTRON
BVD720S, 0-8V, 0-25 A.
PLC:
Siemens S300
Analog Inputs 8 x 12 bit.
E. Carrone,

20. Sensing Board
Vs +
Vs -
E. Carrone,

21. Signal Conditioning ( )
The input stage of the ADC accepts the max Common Mode Voltage UCM= 2.5V. This imposes a Vsensing attenuation via a resistive net (UCM= (Vin+Vo)/2  3.9 V) .
THE NET RESISTOR æ R 2 R 4 ö æ R 4 ö V = V - V = V ç - ÷ + V ç ÷ sr + + s - s in + è R 1 + R 2 R 3 + R 4 ø
sen
sin g è R 3 + R 4 ø R 4 ( ) R 3 + R 4 V = V + V Þ V = V - V sr +
ped
sen
sin g R 3 + R 4
sen
sin g sr +
ped R 4
In order to measure the Vped, Rsens has been put in short circuit (Vsensing=0) and this resulted in Vped=5 mV. To evaluate the Ucm attenuation factor A= R4/(R3+R4), Vsr and Vsensing have been measured and it resulted in A=0.1325:
Vsensing = (Vsr - Vped)/A
Finally
Iload = Vsensing / Rsens
With the ADC LSB of 22.4 mV in the range +-80mV, a current sensitivity
d=LSB/A*Rs= 2.8 mA
on the Iload is achieved. This allows the C.S. to detect the single FEE chip failure which drains 45 mA per polarity.
E. Carrone,

22. PLC VAT (Variable Table)
PIW 288 “V sensing + ADC” --- DEC 8872
PIW 290 “V sensing – ADC” --- DEC
PIW 292 “V load + ADC” --- DEC 15496
PIW 294 “V load – ADC” --- DEC
MD "I load +“ --- REAL
MD "I load -“ --- REAL
MD "V load +“ --- REAL
MD "V load -“ --- REAL
MD "V sensing + input ADC“ --- REAL
MD "V sensing - input ADC“ --- REAL
[V]
[A]
[mV]
Process Input Word
Memory Double Word
ADC “brute” value
E. Carrone,

23. PLC Instruction List TITLE =Sensing Current CH + AN Q 4.1;
  NETWORK
TITLE =Sensing Current CH +
AN Q ;
S Q ;
  AN Q ;
S Q ;
  AN Q ;
S Q ;
  AN Q ;
S Q ;
L PIW 288;
ITD ;
DTR ;
L e-003;
*R ;
T “V sensing + input ADC";
  L e+000;
L “V sensing + input ADC";
+R ;
T MD 68;
  L MD 68;
L e+000;
T MD 84;
  L MD 84;
L e+001;
/R ;
T "I load +";
Relays switches
ADC reading   value [mV]
Integer: bit 32 bit
Pedestal offset
Integer 32 bit   IEEE-FP 32 bit
1/A where A=attenuation factor
V  I Conversion
E. Carrone,

24. Control System for the CAEN SY1527 in the PVSS environment.
The Configuration Program
A devoted program reads from a file the HV sub-system configuration ( # HMPID modules, HVsegment/module) and creates the DataPoint data base in the PVSS environment.
These data points are automatically created according to the specified variables (Crate/Board/Channel) of the CAEN OPC Server and it sets a link between the OPC variable addresses and the PVSS data base.

25. Monitoring panel of the HMPID HV System
Alarm condition
Link to the Monitoring Panel of SY1527
Link to the Monitoring Panel of the HV segment
Segment disabled
“Burned-out” Segment
Link to the
Enable/Disable
Panel
Link to the
Channel Configure Panel

26. Monitoring panel of the HV Segment (when the CAEN SY1527 OPC serv
Monitoring panel of the HV Segment (when the CAEN SY1527 OPC serv. Is running!)
Channel settings
Channel Status
HV-ON
Channel Name
Actual value of Parameters
Trend display settings
Trend parameter Chart

27. Enabling/disabling HV Segments
Option for global Enable/Disable action
Segment Enabled
Segment Disabled
Exit

28. HV Channel configuration
Parameter Value
Parameter Name
Cancel all the changes
Save the present configuration
Exit

29. Crate Front panel status
SY1527 Control panel
Inserted board status
Board description
Power
System Name
Empty slot
Crate Alarm condition
Crate Front panel status
Fan & Power unit Status
Crate commands
Crate settings

30. HMPID DCS: LV prototype panel

31. The Control system of the Liquid Circulation apparatus : from design to implementation
The system description
LCS as a Finite State Machine
the GRAFCET representation of LCS
the Object Oriented Representation Model
the Local / Remote Mode switch facility
the Heart Beat Signal facility
LCS Control System: the Main Program Flow-Chart
LCS the Instruction List v.0.1

32. The Liquid Circulation System
… a Winner approach !!

33. The system description
The aim of this apparatus is to re-circulate the C6F14 liquid radiator into a quartz vessel named RADIATOR in the figure. The hydrostatic pressure ensured by the position of the HEATHER with respect to the RADIATOR, keeps constant the flux. The system consist of a PUMP, three electrovalves EV_1, EV_2, EV_3 and four pressure sensors Pt_2, Pt_4, Pt_6, Pt_9. The tank, the radiator and the header are connected to a gas supply of Nitrogen, and Argon is used to activate the electrovalves just quoted before. The pump fills the HEADER which ensures the constant flux in the radiator once it has been filled.

34. The LCS Control System: a Finite State Machine
First of all, the system is into the OFF state, all the inputs are closed and the system is into a “safety” state.
A START command moves the state from OFF to “Stop”, the critical parameter are tested and the run configuration is load.
The Next command is RUN that move the machine into the “Running” state, the PUMP is switched ON and the pressures are tested, during this phase the liquid fills the Header.
If all the conditions are satisfy, a FILL command put the system into the “Filling” state, then start the radiator filling phase and when its level get the maximum the system moves to the “Ready” state.
A PURGE command, bring the system into the “Purging” state and the radiator is made empty.
When the machine is into the “Running” state a STOP command bring the system into the “Stop” state: the header is purged and the PUMP is switched OFF.
The operator can also decide to run the LCS in the manual mode. In this case, he has to send a MAN command and then system is forced into the “Manual” state.
All the alarm conditions puts the system into an “Alarm” state that provide the “safe mode” operation. Only a RESET command can move the system from this state.
LCS: the bubble chart representation

35. The LCS Control System: the GRAFCET representation
The GRAFCET representation of LCS consist of one Normal GRAFCET, that provides all the operations involved into the regular evolution of the system, and six Master GRAFCET, each one controlling particular functions as Alarm conditions, Break command, ecc.
In red are reported the actions of the Master GRAFCET’s which force the Normal GRAFCET into a defined state.
The NORMAL GRAFCET
The MASTER GRAFCETs
An example of GRAFCET. Transitions: a,b. States: 1,2,3. Actions: S1, S2

36. The LCS Control System: the Object Oriented Representation Model
The Control Program running into the PLC performs the encapsulation of the entire LCS, it exports, to the upper DCS layers, one input COMMAND variable and one output STATUS variable.
This variables are communicated by means of the OPC/DCOM protocol.
Other two service variables perform the role of carriers for Configuration Parameters and Messages.
During the “expert” and “ debugging” operative mode when the system has to allow the maximum accessibility, the LCS object export to the upper level all the internal variables in order to make visible the entire machine domain.

37. The LCS Control System: the Local/Remote Mode switch facility
The Control Program stored into the PLC can run in a “Local Control Mode” or “Remote Control Mode”, in order to implement the facilities for debugging and development phases.
In Remote Mode the system communicates by the OPC link, otherwise, in Local Mode it is connected to a front panel near the PLC.
The control mode is selectable by a PLC switch.

38. The LCS Control System: the Heart Beat Signal facility
ORGANIZATION_BLOCK "Hert Signal Generation"
TITLE = "Cyclic Interrupt"
//Blocco per la generazione del segnale di "Heart" del PLC.
//Ad ogni richiamo viene variato lo stato della variabile heart_signal, oltre ad
//incrementare un contatore. //
//ATTENZIONE ! E' necessario modificare il valore dell'intervallo di richiamo
//portandolo a 1000 ms. (Simatic -> Hardware -> Proprietà CPU -> Schedulazione
//Orologio
VERSION : 0.1
VAR_TEMP
OB35_EV_CLASS : BYTE ; //Bits 0-3 = 1 (Coming event), Bits 4-7 = 1 (Event class 1)
OB35_STRT_INF : BYTE ; //16#36 (OB 35 has started)
OB35_PRIORITY : BYTE ; //11 (Priority of 1 is lowest)
OB35_OB_NUMBR : BYTE ; //35 (Organization block 35, OB35)
OB35_RESERVED_1 : BYTE ; //Reserved for system
OB35_RESERVED_2 : BYTE ; //Reserved for system
OB35_PHASE_OFFSET : WORD ; //Phase offset (msec)
OB35_RESERVED_3 : INT ; //Reserved for system
OB35_EXC_FREQ : INT ; //Frequency of execution (msec)
OB35_DATE_TIME : DATE_AND_TIME ; //Date and time OB35 started
END_VAR
BEGIN
NETWORK
TITLE =Main
A "heart_signal";
NOT ;
= "heart_signal";
= "HEART_LED";
L "heart_signal_counter";
INC 1;
T "heart_signal_counter";
END_ORGANIZATION_BLOCK
Every 500 milliseconds the PLC Operating System automatically run a dedicated job, named OB35, it generates the “Heart Beat” signal, in order to indicate that the PLC is “alive”
The program is shown in figure and it produces a 1 Hz blinking led with a continuos increasing counter as run timer.
One or all the program variables can be exported to the upper layers of DCS by the OPC link.

39. The LCS Control System: the Main Program Flow-Chart
Every Scan Cycle the PLC CPU perform this actions:
Stores the status of inputs into the Process Image Memory (created by the PLC Operative System)
Tests an Interlock line that stop all the processes
Executes the signal conditioning of inputs (trends, thresholds, Boolean expressions)
Tests the Local/Remote Mode Switch
Copies the Commands Variable from the Hardware Inputs (Local) or from the OPC Buffer (Remote)
Calculates all the Boolean expressions that realize the Transition Condition of the GRAFCET
Activate the States, and perform the “entry active state actions “
Execute all the actions related to Active States
Sends to the Outputs the values contained into the Process Image Memory (created by the PLC Operative System).

40. The LCS Control System: the Instruction List v.0.1
BEGIN
NETWORK
TITLE =Main loop Control
// Verifica che lo Switch "Secure" sia ON
A "secure";
JCN fine;
// chiama le funzioni che preparano il ciclo
CALL FB , DB ;// lettura degli input dal pannello o da remoto
CALL FB , DB ;// lettura e valutazione dei pressostati
TITLE =Verifica recettività
// verifica delle recettività per i MASTER
A "Stato_10";
AN "Stato_1";
A "|stop";
= "TR_12";
A "Stato_12";
A "gp4giu";
O( ;
A( ;
O "gp2giu";
O "gp6giu";
O "gp9giu";
) ;
AN "STOPMODE";
= "TR_14";
A "Stato_14";
A "|start";
= "TR_16";
A "Stato_16";
A "|manual";
= "TR_18";
A primary version of Instruction List has been produced
At present it is under debugging and Test phase
In the next future:
Message communication facilities
Configuration procedure
Time synchronization
Measurement of the reaction time
Exploitation of failure and breakdown events and relative PLC reaction
...

41. Next steps:
Since the HMPID DCS has to be fully integrated in the ALICE DCS then a.s.a.p. an advanced version of the JCOP Framework will be available, we intend to integrate there as much as possible of the HV, LV, Liq. Rec. Sub-systems to get a first HMPID DCS prototype. Unfortunately the present version (000921) of the framework doesn’t yet include the physical device SY1527.
As soon as the CAEN SY1527 OPC server will be delivered, we intend to carry out tests on the new version (we hope equipped with the channel grouping management as we asked for to the CAEN)

42. Guidelines to implement HMPID Control Layer
To integrate HV-LV-re_circulating control systems in the first HMPID DCS prototype, we are working on:
Guidelines to implement HMPID Control Layer
Design of the DCS control part as a FSM
Implementation of the control procedure as a PVSS extension in SMI++ language
Use the DIM protocol for the inter-process communication
…..which means
Test the DIM – PVSS integration
Test the SMI++ language into PVSS environment
Design and implement a small control procedure for the performance evaluation
Define the architecture of the lower layers interlock

43. report on DIM Testing phases
DIM tools (already tested)
DIM driver for PVSS - Client Side (under test)
DIM driver for PVSS – Server Side (not yet implemented)
DIM – PVSS performance evaluation …
report on SMI++ Testing phases
Implementation and test of a control DLL into PVSS environment (done)
SMI++ language structure (done)
SMI++ Tools
Implementation and test of a control program in SMI++
Implementation and test of a small FSM in SMI++ into PVSS environment

44. The resulting DIM – SMI++ - PVSS architecture
Develop Phase
Run Time structure
FSM description
DIM
DNS Server
Other Application
DIM protocol based
SMI++
Editing Tools
DIM
Test Tools
SMI++
source code
Other PVSS domain
PVSS domain
PVSS
Data Point DB
User Interface Control Program
Control DLL
DIM
Driver
SMI++
Traslation Tools
SMI++
proxy code
Visual C++
Develop Envir.
PVSS panels
User Interface
PVSS External Control DLL

45. Expectation from the JCOP and CCTeam as conclusion
We propose the JCOP to include in the next release of the Framework an example of DCS based on the Physical Devices CAEN SY1527 and Siemens PLC. It could be a nucleus of running DCS very useful for the sub-detector DCS developers. For this specific case we are available to suggest the Control Hierarchy(how to operate correctly the HMPID HV-LV sub-systems)
The CCTeam should co-ordinate and assists the ALICE DCS developer groups and mediate specific requests with the JCOP.