YSI P 700 IQ Analyzer - Manual (Page 83)

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P 700 IQ
10 Reconnect the plug with the P700IQ-PO4.
or
Switch the analyzer on again with the power switch.
Restarting the
measuring operation
11 Carry out the steps 13…20 in section 5.3.4 Maintenance and
cleaning work on the open P 700 IQ,  73.
5.4.4 Changing the pump tube of the peristaltic
pump
How it functions The liquids are pumped through the P 700 IQ with the aid of a peristaltic
pump.
A peristaltic pump is a displacement pump for the pumping of liquids.
The liquid is in a flexible tube that is fitted in a circular pump housing. A
rotor with several rolls presses down some parts of the flexible tube.
When the rotor is turning, the rolls forward the liquid through the tube.
• The pump tube has a working life of 1500 hours for water. The
chemicals used may, however, reduce the working life.
• The deterioration of the tube quality is a slow process. When the
working life of the pump tube is near its end, the P 700 IQ may have
to be calibrated more often.
• A peristaltic pump can be blocked when it was not used for a longer
period of time, because the parts of the flexible tube that are pressed
down stick together. After a shutdown of several weeks the blockage
is normally cleared after some rotations. After a shutdown of several
months the flexible tube has to be removed and the blockage
cleared by hand.
Maintenance interval 12 months
Parts required • Pump tube PT (see chapter 7. Technical data,  99)
• Mounting aid
Preparations 1 Carry out the steps 1…11 in section 5.3.4 Maintenance and
cleaning work on the open P 700 IQ,  73.
2 Put on protective clothing (lab coat, protective goggles, chemical
resistant protective gloves).