Operation; Powering Up The Vacuum Degasser - Knauer Smartline 5000 Serie Handbuch

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Operation

Powering up the Vacuum Degasser

1. With the Vacuum Degasser installed into the Smartline System, switch
on the Smartline Pump 1000. The green power LED should illuminate.
Upon turning on the instrument, the microprocessor immediately
examines the vacuum sensor signal to confirm that it is within an
expected range. Following the startup test, the microprocessor ramps
the vacuum pump to high RPM, to quickly purge the atmosphere from
the vacuum chamber. As the vacuum level approaches the preset
control value, the pump RPM will slowly ramp down to a low speed
(typically 40 to 60 RPM) and will vary slightly as needed under the
changing degassing load to maintain a virtually constant vacuum
level.
During initial pump-down, the orange INIT LED will be lit. This process
only takes 30 seconds. Once the vacuum has reached normal
operating level, the orange LED will extinguish and the green READY
LED will illuminate.
2. Start solvent flow through the system and check for leaks around the
black flangeless fittings.
If a leak occurs at the connection, tighten the fitting an additional 1/8
turn. If the leak persists, disconnect the leaking fitting and inspect it. If
the nut and ferrule appears to be in good condition, reconnect the
fitting. If the leak persists, replace the nut and ferrule and repeat the
procedure until you achieve leak-free operation.
The Vacuum Degasser maintains a constant vacuum pressure of 50
mm Hg (67 mbar) absolute (nominal) by varying the speed of the
vacuum pump as needed depending on the degassing load in the
system.
The pump is designed to run continuously for at least 5 years and is
equipped with integral in-pump venting, eliminating the need for
stop/start running (U.S. Patent 6,248,157).
The vacuum level and pump speed is constantly monitored by the
microprocessor for changes in operating conditions which might be
attributed to internal chamber leaks.
If a potential leak is detected (if the pump RPM > 300 for 30 minutes),
the pump will be shut down and the orange INIT LED will flash.
The vacuum is maintained as long as the Vacuum Degasser is
powered on. Solvent flowing through the Vacuum Degasser will
continue to be degassed so long as the instrument is on and running.
3. The Vacuum Degasser Unit will be automatically turned off when the
Smartline Pump 1000 to which it is connected is not in use. The
vacuum chamber(s) will slowly return to atmospheric pressure when
the unit is powered off. This is accomplished by a small, in-line
vacuum bleed and reduces the possibility of solvent vapors
condensing in the vacuum tubing or pump head.
4. When flushing a solvent line, the single lumen coil inside the chamber
contains a very small amount of solvent (approximately 480 microliters
for analytical version). When changing from one solvent to another
where the final solvent is immiscible with the first, use an intermediate
solvent miscible with both the initial and final solvent.
Carryover from solvent to solvent is much less than previous PTFE
designs. Once air bubbles have been cleared from the solvent line,
any further bubbles observed will be coming from the solvent reservoir
or from a leaking fitting.
Vacuum Degasser Unit