Working with HIGH VOLTAGE is risky. You never have the chance to correct your error.
parameters for CAEN SY1527
baud rate : 57600 // this is not the default 9600 stop bits : 1 slow-control : xon/xoff parity : noneHow to quit kermit
To quit kermit, press Ctrl-\ then cHow to operate CAEN HV Power Supply
2005-11-24For our application, we have one control board and two 6-channel boards (Slot0 and Slot1) mounted on the front panel of CAEN HV.
Before you want to start CAEN HV, you should find some 50 Ohm termination resistors with LEMO connectors. Put them on RESET, KILL, INTERLOCK and ENABLE for Slot0 or Slot1 if necessary.
CPE cables should be used if you want to connect CAEN to detectors like RPC. WARNING: NEVER connect or disconnect cables if HV is ON.
After you have connect everything, turn on the power by the KEY and the switch labelled with INTERLOCK. Check the signal lights on the front board, make sure that the POWER light is on, the RESET, KILL, INTERLOCK, TRIP, OVC lights are all off. If not, please check if you have put on the appropriate termination resistors.
To control CAEN, a terminal is required. CAEN HV is hooked up with PHENIX4 through RS-232 port. To control CAEN, you should first ssh to phenix4.npl.uiuc.edu then switch to root logon.
Run "kermit -0" and the following commands:
phenix4:/home/yangrz# kermit -0 C-Kermit 8.0.211, 10 Apr 2004, for Linux Copyright (C) 1985, 2004, Trustees of Columbia University in the City of New York. Type ? or HELP for help. (/.autofs/home/yangrz/) C-Kermit>set parity none (/.autofs/home/yangrz/) C-Kermit>set stop 1 (/.autofs/home/yangrz/) C-Kermit>set carrier-watch off (/.autofs/home/yangrz/) C-Kermit>set line /dev/ttyS0 (/.autofs/home/yangrz/) C-Kermit>set flow-control xon/xoff (/.autofs/home/yangrz/) C-Kermit>connect Connecting to /dev/ttyS0, speed 9600. ESCAPE CHARACTER IS DISABLED ----------------------------------------------------
Note that you can put the above commands in a plain text file, and use kermit like this:
kermit <your_filename>
Press any key except ENTER, you will see the main menu.
##### ## ## ##### ####### ##### #######
## ## ## ## ## ## ## ## ## ##
##### #### ## ###### ## ##
## ## ## ## ## ## ##
##### #### ##### ###### ###### ##
C.A.E.N. SY3527 Universal Multichannel Power Supply V1.00
M A I N M E N U
Slot 0 Slot 0 Communication
Slot 1 Slot 1 Communication
I/O Status Display I/O status
Configuration Set Configuration
Reset Reset Slots
Interlock Software Interlock
General General Informations
Update Firmware Update
Select Item [Usage Arrows & <Enter>]
Everything is already setup, so proceed to Slot0 or Slot1.
##### ## ####### ##### #####
## ## #### ## ## ## ##
####### ## ###### ## ######
## ## ## ## ## ## ##
## ## #### ###### ###### #####
C.A.E.N. A1526 (6 CH Neg. 15KV 100uA) V2.04 Slot 00
B O A R D M E N U
Display Display/modify channels
Format Reformat EEPROM
I/O Board Input/Output status
General General board status
Trip Trip configuration
Quit Abandon program
Select Item
Proceed to Display. And here is the interface which we are going to play with a lot:
C.A.E.N. A1526 (6 CH Neg. 15KV 100uA) V2.04 Slot 00 Page 0 V0-SEL I0-SEL Temp. 22 C Channel HVmax Vmon Imon V0set I0set EnEx Pw Status CHANNEL00 16582 00002 0000.00 uA 00000 0010.00 uA On Off CHANNEL01 16582 00000 0000.00 uA 00000 0010.00 uA On Off CHANNEL02 16582 00000 0000.00 uA 00000 0010.00 uA On Off CHANNEL03 16582 00001 0000.00 uA 00000 0010.00 uA On Off CHANNEL04 16582 00000 0000.00 uA 00000 0010.00 uA On Off CHANNEL05 16582 00001 0000.00 uA 00000 0010.00 uA On Off Quit Page Group Mode V/Isel Reset alarm [SPACE to Change]Vmon and Imon are monitors for voltage and current on different channels. V0set is the voltage we want. Just type the number for the setting. I0set is the current limit. Just type the number for the setting. Pw controls On/Off of the corresponding channel. Press SPACE to turn On/Off. During operation, Status will indicate ITrip, Down, Up. ITrip means the over-current situation, and the OVC light on the CAEN main board at the same time. Down/Up means the voltage is going Up/Down. Press P will turn to the other page of this interface:
C.A.E.N. A1526 (6 CH Neg. 15KV 100uA) V2.04 Slot 00 Page 1 V0-SEL I0-SEL Channel SVmax Rup Rdwn Trip Pon Pdwn CHANNEL00 15000 050 200 000.2 On Kill CHANNEL01 15000 100 200 010.0 Off Rdwn CHANNEL02 15000 100 200 010.0 Off Rdwn CHANNEL03 15000 100 200 010.0 Off Rdwn CHANNEL04 15000 100 200 010.0 Off Rdwn CHANNEL05 15000 100 200 010.0 Off Rdwn Quit Page Group Mode V/Isel Reset alarm [SPACE to Change]Rup gives how fast the voltage can go up. It is in Volt/Sec. In order to prevent over-current as we increase the voltage, we set this to 50 now. Rdwn controls how fast the voltage can go down. Trip determines how long the over-current can last. It is in Sec. For safety, we set it to 0.2, the Trip condition can be indicated by Status on the previous page. Pon can be set to On/Off to control whether you can restore the settings before a power-off or restart. Pdwn can be set to Kill or Rdwn. If Pdwn is set to Kill, upon a Trip condition, all channels will be shutdown instantly. For detailed description of those options, please carefully read CAEN manuals.
The general procedure to increase HV to 10kV is:
- Set V0set = 20, I0set = 10, SVmax = 15000, Rup = 50, Rdwn = 200, Trip = 0.2, Pon = On, Pdwn = Kill
- Set Pw = On
- Keep an eye on Status and Imon, if Status indicates ITrip, try to decrease Rup and try again.
- Repeat the above procedure to increase V0set to 100, 200, 500, 1000, 2000, 5000, 10000
WARNING: If you are applying HV to RPC or any other detector, make sure you are flowing gas through the detector. e.g. for RPC, since the gap is 2mm and the discharge length for Air is 1kV/mm, if there is Air instead of Freon in the gas gap it may likely to have discharge at 2kV or higher. Discharge will damage the surface of the detector.
