Reaction cell pressure, with air to ozone generator OFF (0 psi setting on internal
regulator) and transfer line capped: ___________________ torr
Tighten connections if necessary and check to make sure pressure stabilizes in the expected region. If proper pressure is not obtained contact Agilent for assistance. If the reaction cell pressure is within the expected range, record the value, reset the internal air regulator to
Recorder Test
The standard 355 SCD and 255 NCD recorder output configuration is 1 volt full scale. In addition, an output range can be set with the recorder output selection switch located on the back panel (Figure 11). Use a small screwdriver to adjust the switch to the proper position for your integrator or data system.
To check that the recorder cable has been properly connected to the integrator or data system, set the integrator to a high sensitivity setting (e.g. attenuation of x 1) and plot the background signal. Use the Output Offset to decrease the Detector baseline. If the recorder cable is connected correctly, the baseline will shift in response to changes in the Output Offset. If the polarity of the connection is incorrect, a negative response will be observed when the baseline is increased, and vice versa. Switch the polarity of the wires to correct this problem. If no response is observed,
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