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7. Controller – Level 2
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7. Controller – Level 2
7.4.1
Front Panel LE
Ds
•
Power on – green (constant when controller is switched
on; flashing when controller is energized but switched off.)
•
Alarm – red
•
Service / maintenance reminder – amber
•
Filters (pre, after, and pilot) service / maintenance
reminders - amber
•
Inlet switching and purge / repressurization valve status
(On = valve open; Off = valve closed) – green
•
Left and right tower status (regenerating) - amber
•
Left and right tower status (drying) - green
•
Left and right tower pressure switch status (On = switch
closed; Off = switch open) – green
7.4.2
Front Panel S
witches
The front panel contains four momentary-contact push button
switches. Refer to Figure 7-1, Front panel Overlay – Level 2
Controller for the appropriate icon associated with each switch.
Pushing on the overlay icon actuates the switch. Switching can
be affected remotely by wiring external pushbuttons to the RPB
(J2) terminals located on the rear of the display board. Refer to
Section 7.2.4.
7.4.2.1
Dryer On / Of
f Switch
This switch is used to turn the dryer on (run) or off (stop).
Caution: In the event of a loss of power, either intentional
or unintentional, both inlet-switching valves will open and
both purge-repressurization valves will close. A tower
that is actively purging when the power off button is
actuated will be subjected to a rapid repressurization that
can lead to fluidization and subsequent abrasion of the
desiccant bed. Ideally, dryers should be powered off at the
end of any half cycle when both desiccant towers are at
full operating pressure.
Power recovery after an external loss of power is affected by
the programming of the auto restart mode (Program Mode –
Screen 2). Refer to Section 7.7 for additional information.
7.4.2.2
SELECT Switch
This button is located to the left of the text display window.
Refer to Section 7.6 for additional information.
7.4.2.3
ENTER Switch
This button is located to the right of the text display window.
Refer to Section 7.6 for additional information.
7.4.2.4
Alarm Reset
Switch
This switch is normally used to reset an alarm or service
reminder.
Refer to Section 7.9 for additional information.
7.5
Event Sequ
ence and Com
ponent Status
Refer to Tables 7-2, 7-4, and 7-5 for the event sequence,
timing and component status for the Level 2 Controller.
7.6
Front Panel O
peration
In the following sections:
•
E (enter) represents the button to the right of the
text display.
•
S (select) represents the button to the left of the
text display.
1.
There are five operating modes for the Level 2 Desiccant
Dryer Controller.
a.
Program Mode
b.
Setup Mode
c.
Alarm & Service Mode
d.
Display Mode
e.
Test Mode
2.
Each mode is described below.
7.7
Program Mode
1.
Press and hold E and S simultaneously for 3
seconds to enter Program Mode.
2.
Program Mode is comprised of the screens that are
described below.
3.
There are three ways to exit Program Mode.
a.
Press E after making the selection in the
final screen.
b.
At any screen, press and hold E for 3
seconds.
c.
The controller automatically exits Program
Mode if no button is pressed within 60
seconds.
4.
Upon exiting Program Mode the controller will switch to
Display Mode.
7.7.1
Program Mod
e Screen 1
– Select the language.
ENGLISH
•
Press S to scroll through the available language
choices: ENGLISH, DEUTSCH, FRANCAIS, ESPANOL,
and ITALIANO.
•
When finished, press E to save the selection and move
to Screen 2.
7.7.2
Program Mode
Screen 2
– Select the auto restart
mode.
AUTO RESTART
DISABLED
•
Press S to toggle between DISABLED and ENABLED.