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

Page: 36 / 156

ACM 150
36
The typical timing and pressure readings for the various modes of operation with the
5 meter gas cell are:
Table 1. Cycle timing and readings
MODE OF OPERATION TIME IN SECONDS
(typical)
GAUGE READING
(inches of mercury)
Evacuate 1-2 20-30 vacuum
Surge 3-4 5-15 vacuum
Fill 0.5 to 1 increases to 0
Analyze/Bypass 6-8 stays at 0
Background Purge 30-60
(once every 2 hours) stays at 0 or slightly
positive
Background Analysis 30-60 stays at 0
If you observe the Cycle Valve Control Panel, you can follow the modes for each area
scan. You can also observe this on the local or remote computer screen by selecting
View Cycle Valves.
The timing is set by the Honeywell Analytics service engineer in the configuration
software. These times may be increased or decreased to get good sampling and
analysis results in the minimum amount of time. Both the timing and the frequency of
the Background mode may also be changed in the configuration software.
CDA panel
The panel shown below sets and controls the pressure of clean/dry air (CDA). It splits
to two air set regulators, one for the Venturi Pump air supply and one for Line Leak
Test.
Solenoid valve S9 is normally opened to supply air to drive the two Venturi Pumps. It
shuts off automatically when the Backup Exhaust Pump takes over and is manually
reset to open. The venturi regulator is set to 65-70 psig. If the Venturi option is used,
the line leak regulator is set to approximately 15 psig when the test is active. The
needle valve provides a flow restriction so that each line decreases approximately to
0 psig and increases for each tested line as it holds the pressure, as indicated on the
gauge. S10 is closed except during the test mode, when it remains open.