Servomex Servotough SpectraScan 2400, Руководство пользователя

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SERVOTOUGH SpectraScan User Manual
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9.0.2 Zeroing
See
Stream Switching Using External Solenoid Valves on page 52 for information on controlling the
external valves.
1. Purge the cell with the appropriate zero gas: turn off the sample gas and turn on the zero
gas (through software). Refer to the Application data for the appropriate Zero gas
specifications.
2. Make sure that the gas cell is completely purged with the Zero gas by allowing an extra
amount of time in purging (See Table 12 - Response Time Versus Gas Flow Rate).
3. Initiate the command “Zero” from Modbus Master or controller.
(On the Test HMI software, a “Zero” toggle is on the “Configuration” tab.)
9.0.3 Span Verification
Purge the cell with your trusted, certified mixture of sample gas, or verification mixture as follows:
1. Connect the verification gas of choice to the sample inlet supply line if sourcing verification
gas from a cylinder.
2. Turn off the zero gas and turn on the sample gas (either through software in the case of
automated sample-switching configuration or manually).
3. Start collecting data.
4. Wait until data values from the analyzer stabilize. See Table 12 - Response Time Versus
Gas Flow Rate for more information.
5. Record values. Compare data with known values of your trusted, certified verification
mixture.
6. Complete Verification procedure or adjust span values as needed (see next section below).
9.1 Re-spanning
The customer may modify the factory set span values (default values of “1”) for any measurement
channel. This span modification can be done via Modbus/TCP. The span values are multiplied with
the original measured values to produce the final measurement values. For example, adjusting the
span value of a certain channel to 1.05 would adjust the measurement value up by 5%. Similarly,
adjusting the span value to 0.95 would adjust the measurement value down by 5%. Note that the
new span values are NOT stored in the analyzer’s memory, rather, it relies on the Modbus master
program (customer control system) to supply the information.