ASP sterrad NX, Руководство по обслуживанию и устранению неисправностей

Страница: 117 / 126

System Calibration and Verification
7
6. Once the system has stabilized, adjust the zeroing potentiometers on
the vaporizer and chamber pressure transducers so that their pressure
indications match the pressure displayed on the calibrated vacuum
gauge.
7. When completed, vent the system. Remove the vacuum gauge and
adaptor and reinstall the pressure switch.
Leak Test
If the leak test is being performed after a cycle has been run, navigate to
the “heater” screen in service mode. Set the condenser temperature to
70° C. Navigate to the Vacuum/Plasma screen, then open the inlet valve
and pump the system down to less than 100 mtorr for 20 minutes. After
20 minutes, vent to atmosphere (press
Back ). This removes residual
moisture from the system that could impact the leak back test.
1. At the Vacuum/Plasma screen verify the following:
♦
The vacuum valve is closed.
♦
The vent valve is closed.
♦
The inlet valve is closed.
♦
The transition valve is closed.
♦
The oil return valve is closed.
♦
The system is at atmosphere.
2. Turn on the vacuum pump, then open only the vacuum, inlet, and
transition valves.
3. Wait until the chamber pressure transducer reads less than 300 mtorr.
The vaporizer pressure should give approximately the same reading
as the chamber pressure.
To measure the leak back, do the following:
1. Close the vacuum valve and turn off the vacuum pump. Leave the
inlet and transition valves open.
2. Simultaneously measure chamber pressure and start the timer or
record start time including seconds. This is the initial pressure.
Record on the test record sheet.
3. After a duration of at least 10 minutes, measure chamber pressure.
This is the final pressure. Record final pressure and actual duration
on the test record sheet.
STERRAD
®
NX
™
Service Guide 117