Felix Instruments F-900, Руководство по эксплуатации

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F-900 Instruction Manual rev. 1/16/2014
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Ave, Camas, WA 98607, USA Phone (360) 833-8835 Fax (360) 833-1914
sales@felixinstruments.com http://www.felixinstruments.com
15
Electrochemical Sensor Response
The lag in sensor response is a natural phenomenon for charged porous membrane electrodes. The
platinum electrode can be thought of as a series of cylindrical pores. Each of these pores will have a
double layer in the radial direction. The interactions between the molecules, convection from air
movement, electric fields and the concentration gradient result in a lag following a change in
concentration
1
.
Auto-Escape Feature
An upper limit auto-escape feature acts as a safety feature of the unit. This safety feature is always
on. If the sensor detects over 20ppm ethylene, the F-900 will auto-escape from monitor mode to
prevent poisoning of the electrode. This will stop the measurement. If the sensor becomes
poisoned, it will continually auto-escape with the error message "sensor out of bounds". If this
happens, please consult the Setup Sensor Voltammetry section on page 21.
No SDcard Present
If the autosave is enabled and no SDcard is present, the user will be notified by seeing “NO SDCARD”
on the Sensor Status display where the FILE and filename usually are. In order to continue
measuring without an SDcard, the user must press
Enter at the warning screen. Pressing any other
button will return to the main menu. Each time the F-900 tries to autosave, the unit will flash
“write error” instead of “saved” at the top of the display.
1
Kontturi et al., “Ionic Transport Processes: In Electrochemistry and Membrane Science.” (Oxford University
Pess) 2008