Switching On; Switching Off - Grundfos Vaccuperm VGS-141 Installation And Operating Instructions Manual

• Set the current source to 5.6 mA (this corresponds to 10 %).
This and the following step cannot be done without a current
source.
• Check the dosing flow indicated by the measuring tube.
If this is not 10 %:
Reset the zero point. The floater may reach the end stop if the
dosing flow exceeds 0 %.
• Set the current sensor to 20 mA. Use programming buttons L
and SET to set the servomotor to 100 % dosing flow
(as indicated by the measuring tube). The toothed rack on the
regulating valve must not protrude by more than 31 mm.
+0,5
31
+0,5
1 mm
min. Ymin Ymax
^
(ST1) 0% = 4 mA 100% = 20 mA
Fig. 42 Rate valve with gear rack
In case of exceeding: The rate valve may get
Caution
damaged!
• Set the upper limit switch (SL) to a value slightly above 100 %.
• Remount the cover of the servomotor.
6.7.3 Manual operation of the servomotor
2 4
L
SET
R
Fig. 43 Servomotor with analogue control
Item Description
2 Programming buttons
4 LEDs
5 DIP switch
mm
max.
^
(ST2)
5
If necessary, the servomotor can also be operated manually.
Warning
Danger!
Do not touch bare wires or clamp screws!
• Remove the hood from the servomotor.
• Move the switch (item 5, 2) to 'Man'.
• Use programming buttons L or R (item 2) to move the
servomotor to the required position manually.
• Replace the hood on the servomotor.
Switch (item 5, 2) must be reset to 'Auto' for automatic mode.

6.8 Switching on

• Close the rate valve.
• Open the shut-off valve at the injection unit.
• Open the motive water valves.
• Switch on booster pump.
• Open valve of the gas container.
• Slowly open the rate valve until the desired gas flow is
displayed by the measuring tube.

6.9 Switching off

6.9.1 Emergency
Warning
Immediately leave the room in case of gas break-out
and put on safety equipment!
Then start counter-measures!
• Put on safety equipment!
• Immediately close all container valves.
• Let the plant run until all parts are evacuated from the dosing
medium.
• Switch off the plant as described in the following.
Warning
Repairs of components of the system only by
authorized personnel!
6.9.2 Short-term stop (up to 6 hours)
• Close the rate valve.
• Switch off the booster pump.
• Close the motive water valves.
• Close the shut-off valve at the injection unit.
6.9.3 Long-term stop (while the plant is still running)
• Close all container valves.
• Let the plant run until the measuring tube shows no more gas
flow.
• Close the rate valve.
• Switch off booster pump.
• Close the motive water valves.
• Close the shut-off valve at the injection unit.
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