Casella CEL AFC123 User Manual
Page 11
Casella USA
17 Old Nashua Road #15
Amherst, NH 03031
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www.casellausa.com
TF (800) 366-2966
AFC123
Personal
Sampler.
Page
11
Handbook No. HB3182-02 Issue2/JULY 1994
Set the power supply to minimum voltage and current limit to 200mA.
Adjust the test rig and power supply to give a flow rate of 2 litres/min. at
40cm H2O. The voltage should be less than 3.6 volts at a current of less
than 130mA.
If unable to achieve this performance:
For high voltage:
1. Check for leaks using test rig.
2. Check that diaphragm is assembled tightly to the connecting rod.
3. Check the valves for leakage, this can be done by using the 'u' tube
manometer.
Leakage could be due to valve retaining force being to low, apply pressure
to head of retainer and move small 'o' ring to increase retaining force. Valve
surfaces or valve seat surfaces imperfect, discard and replace.
For high current:
1. Poor alignment between eccentric, bearing and connecting rod
components.
2. Adjust bearing position for minimum current.
3. Valves too tight, relieve retaining force.
4. The motor body can sometimes be rotated in its housing and the position
of the eccentric on the motor shaft can also be adjusted to give its natural
alignment with diaphragm centre line to affect a reduction of current
consumption of as much as 10mA.