
B–70115EN/03
E. CONTROL SEQUENCES
IN LASER OSCILLATOR
APPENDIX
459
HV=ON When HV is turned on, laser can proceed to the next
sequence. HV ON can either be done in manual mode or
automatic mode using PMC.
LRDY=OFF When HV is turned on, LRDY becomes off.
PSS1–8=SET This is to select power units and usually is sent to the
units selected by PRM15025 to 15028 [201 to 203]
PSRDY=ON This is the signal to make DC unit ready, and is sent to
the units selected by PSS1–8.
RFHV=ON DC voltage is supplied to RF unit from DC unit.
4
3
BIAS COMMAND
Tube
0
NO
YES
BIAS COMMAND
GAS PRESS CONTROL
NO
YES
PRM15220 [247]
PRM15220 [247] WAIT
voltage < PRM15221 [248]
ALM4066 [666] display
PRM15241 [237] → PRM15242
15243 [236]
PRM15220 [247] → PRM15223 [250]
ALM4078
[678]
PRM15242, 15243[236]–100
< PRM15242, 15243[236]
< PRM15242, 15243[236]+100
³
In order to begin discharge, power command is increased in ramp mode
by BIAS COMMAND. This ramp input is clamped by the value of PRM
15220 [247] (maximum bias command in discharge start). The time
required to reach peak value is 6 sec. During this time discharge takes
place. Intra–tube voltage decreases, upon discharge start, and then takes
a constant value. The BIAS COMMAND after reaching peak is retained
for the time designated by PRM15222 [249] (discharge start waiting
time). Then the comparison is made between intra–tube voltages and
PRM 15221 [248] (discharge start voltage). If the monitored voltage is
lower than PRM15221 [248], discharge is confirmed. When this normal