13
4.3. Switching OFF And Venting
Before coming to rest after switching off, the turbopump must
be vented in order to prevent contamination.
➡
Close the fore-vacuum.
➡
Switch off the turbopump with switch S1 on the power
unit.
➡
Venting
There are three possibilities to vent turbopump:
– M
Ma
an
nu
ua
all vve
en
nttiin
ng
g
Open the venting screw (on delivery, screwed in) on the
venting connection about one turn.
– V
Ve
en
nttiin
ng
g w
wiitth
h tth
he
e V
Ve
en
nttiin
ng
g V
Va
allvve
e T
TV
VFF 000055 (accessories)
Venting release via the remote control (please see
Section 4.7.) or via the serial interface which is
selectable via DCU or interface (see Operating
Instructions, "Pumping Operations With The DCU",
PM 800 547 BN).
– V
Ve
en
nttiin
ng
g iin
n ttw
wo
o sstta
ag
ge
ess when the vacuum chamber
should be vented as quickly as possible.
First stage: venting with a pressure increase rate of
15 mbar/s for 20 seconds.
Second stage: venting with an optionally large venting
valve.
The valve cross-section for a venting rate of 15 mbar/s
must be compatible with the size of the vacuum chamber.
Where small vacuum chambers are involved, the
Pfeiffer Vacuum Venting Valve TVF 005 can be used for first
stage venting.
➡
Shut off water supply (if installed).
4.4. Operations With The DCU 001/DCU 100
Operations with the DCU 001 or DCU 100 should be carried
out in accordance with the relevant Operating Instructions
PM 800 477 BN (DCU description) and
PM 800 547 BN (operating the pump with the DCU).
Where operations with the DCU are
involved, the remote plug 8d on the TC 600
(please refer to Section 2.1.) should be
disconnected.
4.5. Gas Type Dependent Operations
Water cooling is required if the pumps are to be
operated with gas load.
CAUTION
☞
PLEASE NOTE
Where high level gas loads and rotation speeds are involved,
the resulting friction subjects the rotor to the effect of great
heat. To avoid over-heating, a power rotation speed
characteristic line is implemented in the TC 600; this ensures
that where maximum gas loads are involved, the pump will
operate at any rotation speed without the danger of damage
arising.
The maximum power is dependent on the type of gas. Two
characteristic lines are available for any type of gas in order
to fully exploit the power potential of the pump:
–
"Gas-Mode 0" for gases with molecular mass
≥
40 as, for
example, Argon;
–
"Gas-Mode 1" for all lighter gases.
Works setting: "Gas-Mode 0"
➡
Set the applicable gas mode on the TC 600 via the DCU
(please refer to Operating Instructions ”Pumping
operations with The DCU” PM 800 547 BN).
Pumping gases with molecular mass
≥
40 with
the incorrect gas mode can cause damage to
the pump.
For the vertex of the power characteristic line please refer to
Section 9. Technical Data.
Maximum power is applied when the pump starts in order to
limit the time required. Once the set rotation speed is
attained, switching to the selected power characteristic line
is automatic.
If the gas dependent maximum power is exceeded, the
rotation speed is reduced until equilibrium between the
permissible power and gas friction is attained. The power
limitation serves to protect the pump against thermal over-
loading. In order to avoid rotation speed fluctuations it is
recommended to set, in rotation speed setting mode, the
equilibrium frequency or a somewhat lower frequency.
There can be types of pump whereby there is
no differentiation between the two ”gas
modes” settings.
☞
PLEASE NOTE
WARNING
Power
Frequency
D
B
C
A
D-C = Gas mode «0»
B-A = Gas mode «1»
Run up
fnom
Gas type characteristic line
