2
Part One
The S
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device informs the laboratory users when the laboratory is under proper pressure, and provides
alarms when the room pressure is inadequate. If the room pressure is in the safe range, a green light is on. If the
pressure is inadequate, a red alarm light and audible alarm turn on.
The S
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controller consists of three pieces: pressure sensor, Digital Interface Module (DIM), and Adaptive
Offset Controller (AOC). The components are typically located as follows; pressure sensor above the laboratory
entrance, DIM is mounted close to laboratory entrance, and the AOC in the ceiling space near the laboratory
entrance. The pressure sensor continuously measures the room pressure and provides room pressure information to
the DIM and AOC. The DIM continuously reports the room pressure and activates the alarms when necessary. The
AOC controls the supply and exhaust dampers to maintain the pressure differential. The AOC is a closed loop
controller that is continuously measuring, reporting, and controlling room pressure.
Useful User Information
The DIM has a green light and red light to indicate room pressure status. The green light is on when the room has
proper room pressure. The red light comes on when an alarm condition exists.
Sliding the door panel to the right reveals a digital display and keypad (Figure 2). The display shows detailed
information about room pressure, alarms, etc. The keypad allows you to test the device, put the device into
emergency mode, and program or change the device parameters.
Figure 2: Digital Interface Module (DIM)
S
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controller has two levels of user information:
1. S
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has a red light and green light to provide continuous information on room pressure
status.
2. S
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controller has a hidden operator panel providing detailed room status information, self-
testing capabilities, and access to the software programming functions.
NOTE
: The unit provides continuous room pressure status through the red and green light. The operator panel is
normally closed unless further information on room pressure status is needed, or software programming is
required.
