Honeywell ACM 150 Manual To Installation, Operation, And Maintenance page 23

ACM 150
inadequate pressure during the cycle.
• ZPD: The Zero Path Difference indicates the intensity of the infrared signal
measured by the detector.
• If the values are no longer in the green range, there may be a problem requiring
service attention.
• Control Panel Status: Refer to
and Comm. Active LEDs have the same functions on all three control panels.
The LEDs 1 to 8 light to indicate which valves are active during each sampling cycle.
LEDs 1 to 6 correspond to valves S1-S6 with S7 and S8 provided for future use.
When the ACM 150 monitor is in the Frontpanel Mode, press the buttons to activate
the momentary test switches for test purposes. In other modes the switches are
inactive.
Figure 10. Cycle valve control panel
Pump assemblies
Venturi Pumps
The ACM 150 monitor has two air-driven eductors (venturi pumps). One is the
Bypass Venturi Pump. It draws a constant flow of air through the tubes and the
sample valves. This flow is only interrupted when the sample valve is energized, i.e.
when that area is being sampled by the ACM. When areas are not sampled, they
flow to bypass. This assures that the samples lines are continuously flowing and
refreshed.
Control panel status. The Power On, Manual Mode
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