Transcript ALICE

TPC laser system controls
Laser hut
adjustable
mirrors
Laser
Controls,
Power,
Cooling
DCS:
1/ Laser
2/ Mirror adjustments
4/ Interlocks
TPC/TRD DCS meeting, GSI, 27 Sep 2002
3/ Beam monitoring cameras
Børge Svane Nielsen, NBI
1
Spectron UV laser
2 UV Lasers supplied by Spectron Lasers (UK):
Rack with power supply and water cooling.
Controlled and monitored by RS232 to simple DOS program.
TPC/TRD DCS meeting, GSI, 27 Sep 2002
Børge Svane Nielsen, NBI
2
Spectron UV laser
In ALICE:
 Lasers placed in pit in enclosed hut outside shaft side
magnet door
 Full control of laser operation must be possible remotely
 Full monitoring of laser state must be possible remotely
 Existing Spectron software is not suitable.
Spectron is developing a Windows based RS 232 human interface
and a new RS 485 based bus interface.
May be useful  PC in the laser hut + accessible remotely
Alternatively, develop our own software to access the RS 232 port.
Could be done in LabVIEW.
Some ALICE wide ’standard’?
PC either in laser hut or in counting room.
TPC/TRD DCS meeting, GSI, 27 Sep 2002
Børge Svane Nielsen, NBI
3
Mirror adjusters
Based on commercial solution
 3 fully adjustable mirrors per half-TPC
RS 232 or RS 485 interface
TPC/TRD DCS meeting, GSI, 27 Sep 2002
Børge Svane Nielsen, NBI
4
Mirror adjusters
In ALICE:
 Mirror holders placed in laser hut and on TPC end-plates
 Full control must be possible remotely
 Automatic adjustments with feed-back from
online beam monitoring
New Focus provides interface software for RS 232 or RS 485 connection,
but probably only useful for manual adjustments.
Develop our own software for automatic adjustments.
LabVIEW drivers exist.
Some ALICE wide ’standard’?
PC either in laser hut or in counting room.
TPC/TRD DCS meeting, GSI, 27 Sep 2002
Børge Svane Nielsen, NBI
5
Beam monitoring
Beam quality and
position monitoring online
by video cameras
(several frames per second)
 5 video cameras per half TPC
Each camera need low voltage power and coax cable connection
TPC/TRD DCS meeting, GSI, 27 Sep 2002
Børge Svane Nielsen, NBI
6
Beam monitoring
In ALICE:
 Video cameras placed in laser hut and on TPC end-plates
 Full control must be possible remotely
 To be used for automatic beam controls through
mirror adjustments
Camera type has not been chosen, but will be similar to Web cameras.
Display programs probably only useful for manual operations.
Develop our own software for automatic adjustments.
LabVIEW ?
Some ALICE wide ’standard’?
PC either in laser hut or in counting room. Same PC as mirror controls.
TPC/TRD DCS meeting, GSI, 27 Sep 2002
Børge Svane Nielsen, NBI
7
Interlocks
Interlock of laser beams:
 Hardware interlocks through beam shutter
 Hardware interlocks of lasers
 Software shutdown
to be discussed with TIS
TPC/TRD DCS meeting, GSI, 27 Sep 2002
Børge Svane Nielsen, NBI
8
TPC laser controls:
summary of equipment
 High voltage and cooling of lasers:
 HV and flash pulse circuit
 cooling water circulation unit
 control interface to RS232 or RS485
Rack unit supplied by Spectron Lasers company
 Mirror adjustment controls:
 piezo electric drives with separate controller units
 10-20 individual motors
 Beam monitor cameras:
 video cameras for beam position monitoring
 10-20 cameras
 Beam interlocks:
 hardware and software interlocks, to be discussed
TPC/TRD DCS meeting, GSI, 27 Sep 2002
Børge Svane Nielsen, NBI
9