fann MACS II, User Manual, Page: 49 / 165

MACS II User Manual
101796668 Revision E 40
pressure control activity is suspended. Pressure control is resumed once
the measured pressure drifts outside of this tolerance value. The
nominal tolerance for the machine is 200 PSI.
b. SGS DeadBand – This works in the same manner as “Normal
DeadBand” except that it is effective only during the Static or Gel phase
of the test. Normally during the Static or Gel phase, any pumping of
pressure disturbs the gel formation of the cement. By selecting a higher
value of pressure tolerance such pumping can be prevented. The
disadvantage is that pressure may drift from setpoint by the tolerance
specified. Typically this value is set to 1500 PSI.
4. Cooling – The cooling action of the machine is controlled by settings in this
group.
a. Auto Cool After Test – If this check box is chosen the machine begins
a cooling cycle after test is over.
b. AirWater Switch – This determines the cooling medium used for
cooling. If the heater temperature is above this value, then air is used
as the cooling medium. If the heater temperature is below this value
then water is used as the cooling medium.
Be careful when selecting the AirWater Switch
temperature. If temperature is above 212°F, then the unit
uses water to cool a heater above the boiling point of water
and superheated steam will come out of the Hot Out line at
the back of the machine.
c. Cooling Off – This determines at what sample temperature, cooling
automatically turns off.
d. Chiller On – For tests below ambient, an external chiller can be
employed. This setting tells the machine to use chiller below the
specified temperature. The chiller runs continuously once the
temperature setpoint is below the Chiller On temperature.