Low Speed Operation - Varian Turbo-V 70 Notice De Mode D'emploi

Low Speed Operation

With the FRONT panel operation selected, the remote
and RS 232 operations are inoperative; conversely, the
CYCLE NUMBER and PUMP CURRENT pushbuttons
are always active, even when the operating mode
selected is REMOTE or RS 232.
This feature is provided for operating the pump at
moderate high pressure with high gas throughput. To
operate in this low speed mode, engage the LOW
SPEED push-button once if the display shows:
N O R M A L
X X
or twice if the display shows other parameters, either
before starting the pump or after it is operating.
If LOW SPEED is selected before starting the pump,
the display shows:
R E A D Y F O R
S O F T S T A R T
The pump reaches the Normal high speed, then
decrease the speed to the low speed value and the
display shows:
A P P R O A C H
X X
If the Soft Start has been deselected the display shows:
P U M P R E A D Y
S T A R T
where: LS = means low speed mode is selected.
NOTE
O P E R A T I O N
K R P M
L O C A L
I N G L S
K R P M
: P U S H
B U T T O N
After starting, a LS appears on the right bottom corner
of the following displays:
S O F T
[
P U M P
1 2
N O R M A L
With normal LOW SPEED operation, the pump will run
at about 2/3 of its nominal speed and achieves a base
pressure
specifications. If the gas load becomes higher, the
controller output frequency and voltage start to
decrease automatically, and the Turbo-V pump is
slowed down in proportion to the gas load until it
reaches about 9 KRPM.
If the LOW SPEED mode is selected after normal
operating condition is reached, the display shows:
L S
A P P R O A C H
while approaching the low speed value.
When the low speed mode is deselected, the pump
L S
starts to accelerate to its rotational speed.
When this is reached, the display will be as shown in
the following figure.
N O R M A L
L S
58
TECHNICAL INFORMATION
S T A R T
- - - - - - -
I S S T A R T
X X K R P M
O P E R A T
X X K R P M
somewhat higher than
I N G
X X K R P M
O P E R A T
X X K R P M
87-900-870-01 (B)
O N
- - - ] L S
I N G
L S
I O N
L S
the standard
L S
L S
I O N