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9. Put the pump in Automatic mode. The “Pump” switch has three setting:
-
Up:
Manual: The pump will apply pressure to the cell as long as the
switch is held down. This mode is primarily intended for diagnostic
purposes and is not recommended for testing.
-
Middle:
Off: The pump will not engage.
-
Down:
Automatic mode: This allows the Eurotherm and software to
control the pump. This is the correct mode for testing.
The Pressure Regulator controls the air to the pump. When more air is
supplied to the pump, the pressure in the cell will build faster with each
pump stroke. Also, more air to the pump allows more pressure inside the
cell.
For most tests, the regulator can be opened all the way (clockwise). This
will allow the maximum amount of air to the pump and allow the cell to
reach the maximum pressure of the machine. However, for tests at the
lower end of the range, opening the regulator completely may provide too
much air and cause the pressure to continually overshoot. If this happens,
close the regulator by turning it counter-clockwise.
This is a trial-and-error process. The goal is to set the regulator high
enough to reach the pressure required for the test, but not so high that the
pressure overshoots repeatedly.
10. Turn the heat on.
11. Start the test:
a. If you are running a test with the computer, click the “Start Test”
button. Refer to page 17 for more information.
b. If you are running a test without the computer, push the “RUN/HOLD”
button on the temperature and pressure controller. Select the test to
run and press the “RUN/HOLD” button again to start the test.
12. Turn the “Timer” switch on and push the “R” reset button on the timer
display.
The timer displays elapsed time to the nearest tenth of a minute. If an
alarm condition occurs, the timer will stop. This is a troubleshooting
measure that shows you the point during the test at which the alarm
occurred.
The “Timer” switch provides power to the timer and the “R” reset switch
resets the timer to zero.
13. If the “Alarm” switch is not already on, turn it on now. If the “Alarm” switch
is left off, the unit can still enter into an alarm condition, but there will be
no visual or audio signal to notify the operator.