Low Speed Operation - Varian Turbo-V 250 969-9504 Bedienungshandbuch

Low Speed Operation

With the FRONT panel operation selected, the remote
operation is inoperative; conversely, the CYCLE
NUMBER and PUMP CURRENT pushbuttons are
always active, even when the operating mode selected
is REMOTE.
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 pushbutton 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
H
1 2
and when the pump reaches th low speed value,
display reverts to:
N O R M A L
L S
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
L S
slowed down in proportion to the gas load until it
reaches 3 KRPM.
If the LOW SPEED mode is selected after normal
operating condition is reached, the display shows:
A P P R O A C H
L S
while approaching the low speed value.
When the low speed mode is deselected, the pump
starts to accelerate to its rotational speed.
59
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
I G H L O A D
X X K R P M
O P E R A T
3 7 K R P M
somewhat higher than
I N G
X X K R P M
87-900-856-01 (B)
O N
- - - ] L S
I N G
L S
I O N
L S
L S
I O N
L S
the standard
L S
L S