Galvanic Applied Sciences ProTech903, Руководство по эксплуатации

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Revision 14
25 August 02, 2019
Table 2-1: Read/Rate Aperture Strip Sizes and Associated Ranges
Maximum Range (ppm) Aperture Strip Size Part Number
<1 ppm Wedge MC1136
0-5 ppm 3/16” MC0571
0-10 ppm 1/8” MC0412
0-20 ppm 1/16” MC0410
0-50 ppm 1/32” MC0409
50 – 300 ppm 1/64” MC0570
300 – 500 ppm single hole (high range) MC0572
The range for each read/rate aperture strip size is the range between the maximum range of
the next largest aperture strip size and the maximum range of the given aperture strip size. In
addition, the system is capable of measuring ranges outside those listed in this table – please
contact Galvanic Applied Sciences for more details.
2.7.3 Sensor Block
The sensor block consists of two electronics boards, a microprocessor board, and a
colorimetric detector. The sensor block is shown in Figure 2-8.
Figure 2-8: Sensor Block (From Left: Top View, Side View, and Installed View)
The sensor block measures the intensity of light reflected off of the lead acetate tape. The
light emitting diode emits a beam of red light that passes through the rear window and the
rate/read aperture strip and is reflected off of the lead acetate tape. The reflected light then
passes back through the aperture strip and rear window to reach the photodiode detector,
where it is measured. As the stain on the tape gets darker and darker while exposed to H
2
S,
the amount of light reflected back to the photodiode detector is reduced. The change in the
amount of light reflected back to the photodiode detector is directly proportional to the
concentration of H
2
S in the sample gas.
The sensor block communicates with the electronics assembly via an RS-485 connection. If
the connection between the sensor block and the electronics assembly is broken for any