The peristaltic pump can be found on almost all CEMS systems where we are removing moisture. The water coming from the bottom of the chiller is milked out to a drain from the peristaltic pump with one roller connecting before the other releases so air cannot come in. 
Chopper Motor.... After removing the IR source we can see how the source is aimed through the cell with the chopper motor rotating across its view of the detector. The detector is looking at the source with the chopper motor interrupting it with different filters and cuts which tell the analyzer what position the wheel is at. Lets say you fill one filter with N2 and another with 100% C3H8 and each revolution it could see these. Then you calibrate the analyzer and it has away to compare it's zero point and span point on every revolution. How fast do you think the motor is spinning? Notice the different size to the cuts in the wheel. The filters are sometimes called cuvets.  
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