yellow jacket 40870, User Manual

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in vacuum pressure during a system evacuation. Because the evacuation operates on a
logarithmic scale, the resolution of the needle movement increases in a deeper vacuum meaning
small fluctuations in vacuum pressure become more apparent in a deeper vacuum.
Interpreting the Evacuation Graph:
In addition to the evacuation gauge, evacuation mode also features a fully functional evacuation
line graph like those in Pressure/Temperature mode. Unlike the pressure and temperature
graphs, the evacuation graph features a logarithmic y-axis. This means that the evacuation graph
captures the full scale of an evacuation but is more precise in a deep vacuum allowing the user
to observe small fluctuations in vacuum pressure. An orange leader line is used to plot new data
from left to right. This function allows the user to compare old data to newer data as each
measurement is recorded and displayed. The line graph fully overwrites the old data every 200
seconds (approx. 3.5 minutes) and will begin again from the left side of the graph.
Operating the Evacuation Mode:
Before beginning an evacuation, connect the YJ Vacuum Probe (67044) to either the A1 or A2
connectors on the back of the device. Connect the vacuum probe to the system at a sufficient
distance from the vacuum pump such that it will not disturb the vacuum reading. Use the
“Target” and “Hold” buttons to set the target vacuum level and vacuum hold timer respectively.
Pressing each of these buttons will cycle between a range of available values, with the last value
selected being automatically saved. Target vacuum level can be adjusted in 6 increments: 200,
300, 400, 500, 750, 1000microns (or equivalent selected vacuum unit). Vacuum hold timer can
be adjusted in 7 increments: 1m, 3m, 5m, 10m, 15m, 30m, None.
The session timer, displayed in the top right corner will begin incrementing the moment
evacuation mode is entered. Use the session timer to monitor the overall length of the
evacuation session. While evacuating a system the %/min will change to reflect the current %
change in vacuum pressure every minute. A larger number will indicate a faster evacuation rate
than a lower number. Additionally, the estimated time remaining is denoted by ETR and will
adjust based on the current %/min and the target vacuum level setting.
Once the set target vacuum level has been reached, the vacuum hold timer will start to deplete.
When the hold timer reaches zero, an alarm will sound indicating the evacuation has been
completed. In addition, the user will be prompted to start a pressure hold test as shown in Figure
20. By tapping the button “Begin Pressure Hold Test?” the user will be taken to the pressure rise
setup screen and the alarm will be silenced. If the button is not selected, the user will remain on
the evacuation screen. To silence the alarm, adjust the desired target vacuum level and continue