Buchi DuMaster D-480, Operation Manual

Page: 172 / 354

Operating instructions DuMaster D-480 ©BÜCHI Labortechnik AG
8 - Maintaining the instrument 172

Close the "Replace part" dialog in the operating software. To do so, click
Finish
in the "Replace
part" dialog. This automatically switches on the gas again and the atmospheric nitrogen is
removed by flushing with CO
2
.

Reduce the carrier gas pressure at the delivery point until the CO
2
flow meter displays approx.
400 ml/min "Flow CO2" on the screen.

Wait the required conditioning time. Refer to the above table "Conditioning for combustion tube,
post combustion and Reductor".

Close all open ends of the reaction tubes again.

Set the carrier gas intake pressure on the cylinder manometer so that...

... the "Pressure" display shows 1300 - 1350 mbar on screen.

... the measuring gas flow meter "MFC CO2" displays 700 ml/min on screen.

the CO
2
flow meter "Flow CO2" displays approx. 700 ml/min on screen.

Decide:
If the operating software status view displays...

... approximately the same flow and pressure values as prior to maintenance work are
displayed: The instrument is ready to measure again.

... distinctly different flow and pressure values to those displayed prior to maintenance work
are displayed: Perform a leak test. See Performing a leak test. The instrument is only ready
to measure when the leak test is successful.