Diablo 5000B, Getting Started Manual

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Setting up the Hardware
14 Diablo 5000B Real-Time Gas Analyzer Getting Started Manual
2 Press [Select] four times so that Units is indicated. Use the [Raise] and [Lower] buttons to
scroll through the options until Torr is shown. Press [Select] to choose Torr; the controller
will advance to the Calibrate option.
3 Press [Select] again to move to the Full Scale option. Make sure that the controller is set to
the pressure sensor channel, CH1 or CH2. If you are using a single-channel cable to
connect the pressure sensor to the controller, then select CH 1. If you are using a dual-
channel cable, then select the channel that is identified in the label on the cable that is
connected to the sensor. Use [Raise] and [Lower] to set the full scale value to that of the
sensor. For the sensor supplied with the RTGA interface, this value is typically 2 torr.
However, you should confirm this by referring to the label printed on the side of the pressure
sensor.
Figure 5: The MKS PDR2000 pressure controller.
The controller is now configured and ready to be zeroed.
To zero the pressure sensor:
Note : The pressure transducer is zeroed at the factory. You should only re-zero the sensor if you
are certain that the calibration has drifted.
Important : Do not zero the pressure sensor if there is a leak anywhere in the interface assembly.
To check the current zero setting, make sure that the roughing pump for the interface is on. Close
the isolation valve to the mass spectrometer and plug the sample input and output branches on the
sampling tee. Allow the roughing pump to run for at least 15 minutes. The pressure should stabilize
near 0 Torr.
Important : The pressure should have been powered and heating for at least 4 hours before
attempting to zero the signal.
The pressure sensor can be zeroed in two places. A zero adjustment is located on top of the
transducer itself and can be turned to zero the pressure reading with a small flat-blade screwdriver
(MKS 728A sensor) or by pressing a recessed zero button (MKS AA02A sensor). Zeroing can also
be done on the controller front panel. Make sure that the channel selection is on the pressure
sensor to be zeroed (typically CH 1). Press the [Select] button until the Zero LED is lit. Using the
[Raise] and [Lower] buttons, adjust the readout to 0.000 torr.
If the sensor still cannot be zeroed, please refer to the MKS manual included with your system.