Agilent Technologies SIPS 10, Руководство пользователя

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Maintenance
Agilent Sample Introduction Pump System SIPS 10/20 User’s Guide 69
4
Reconnect the tubing at the Mariotte vessel again and observe
what happens with the air bubble. With SIPS running at full
pump speed, the air bubble should be moving slowly towards the
T-piece.
If the air bubble is moving quickly, the nebulizer uptake rate is
excessive. Although this will not affect SIPS operation, sensitivity
will be reduced and diluent consumption will be high. Adjust the
nebulizer to reduce the uptake rate as described in the ‘Nebulizer
Setup’ section, Page 43. Check that it is in the high solids position, or
an intermediate setting between the high solids and the high vac
position.
If the air bubble is not moving at all, or moving back towards the
Mariotte vessel, the nebulizer uptake rate is less than the
recommended level of 5 mL/min. Adjust the nebulizer to increase the
uptake rate (e.g. adjust the capillary so that it is closer to the high vac
position). Alternatively, and if it is not possible to increase the
nebulizer uptake rate as described previously, modify the method
being used to reduce the pump speed from the maximum speed
setting (100%), i.e., modify the
Nebulizer Uptake Rate field on the
SIPS page.
After making the necessary adjustments, introduce another air
bubble in the tubing from the Mariotte bottle and observe if the air
bubble is moving slowly towards the T-piece.
To check the nebulizer uptake rate:
1
Remove the capillary tubing connecting the T-piece to the
nebulizer.
2
Fit a normal capillary tube to the nebulizer and measure the
uptake rate of the nebulizer.
Record the result obtained. If necessary, modify the methods being
used to change the entry for the sample pump speed, i.e., modify the
Nebulizer Uptake Rate field on the SIPS page. This will ensure that
there is always a positive delivery of diluent, even with SIPS running
at full speed.