Servomex SERVOPRO Plasma, Руководство оператора

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Plasma Gas Analyzer
40 02001001A_9
Other messages can be displayed where the ppm value is normally displayed. You may get
"Under scale" if the cell count or the calculated ppm value is too low for that scale.
"Over scale" will be displayed if the cell count or calculated ppm value is too high for the scale
in use. "Plasma off" will be displayed if the plasma is off. "Waiting" will be displayed if the
plasma stays off for about 1 minute. In this case, the sample flow will be stopped to protect the
valve. This is a short time operation, however,
the sample must always be connected and
flow must pass thru the analyzer .
Other messages can appear depending on options or custom features ordered (auto-zero,
auto-span).
When an error is detected, the status (ST) digital output will be deactivated (contact open).
NOTICE: When the flow is lower than 20 cc for longer than 30 seconds, an internal relay will
shut down the plasma generator and the appropriate message will be displayed.
When the flow comes back to normal, the generator restarts.
5.7 Special consideration about the 0 - 1 ppm range
When the 0 to 1 ppm range is selected, the system is very sensitive. The display resolution is
fixed at 10 ppb. In order to use this range efficiently, it is very important that the connections be
leak-free, that there is no moisture and no quick connector and that the unit is installed and
started up properly. It may take some time to get a stable reading. On this range, the response
time is longer. The by-pass flow must be constant, and vent line pressure must be at
atmospheric pressure. Do not forget: NEVER USE LINES OTHER THAN STAINLESS STEEL
FOR THAT TYPE OF MEASUREMENT
.
It is normal to see the display reading change slowly on this range.
If you analyse pure argon on this scale, you will get a good approximation of its quality.
It is possible to verify and calibrate this range using the flow dilution technique instead of a gas
cylinder. It is very difficult to use gas cylinders for calibration on this range, because very careful
handling is required. We use the dilution technique.