Galvanic Applied Sciences ProTech903, Руководство по эксплуатации

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Revision 14
26 August 02, 2019
reason, a Sensor Communication Alarm will be triggered and the analyzer is considered to be
in a Fail State.
The sensor block contains a temperature sensor that measures the ambient temperature
near the sensor block. This temperature sensor can be used to trigger alarms should the
ambient temperature rise above or drop below set amounts, values that can be set in the
GUI.
The sensor block plays a key role in the tape advance algorithm. While the tape advance
motor is running, the sensor block receives pulses from the Optical Encoder. When the
sensor block receives the number of pulses set in the GUI it sends a message to the
system’s main processor. The processor then sends a message to the motor to stop
advancing the tape.
2.7.4 Compression Head
The compression head is the component in the tape transport system that seals the lead
acetate tape up against the sample chamber so that the lead acetate can react with the
hydrogen sulfide in the gas stream. The compression head is shown in Figure 2-9.
Figure 2-9: Compression Head
The compression head is comprised of a black low-friction plastic held up against the tape
and sample chamber by means of two springs. The low-friction plastic construction ensures
that the tape moves smoothly past the compression head, preventing tape breakage.
The compression head creates a seal between the tape and the sample chamber and it
ensures that the stains on the tape are even and have sharp edges, which produces much
better results. In addition, because the low friction plastic is black, it prevents stray light from
being detected by the photodiode on the sensor block. This in turn prevents inadvertent
triggering of high concentration alarms, as stray light could make the system report that it was
analyzing a much higher concentration gas than it actually is.