T-318
4
−
3
4.3.3 Vent Position Sensor
The VPS allows the user to determine position of the
fresh air vent via Cd45. This function code is accessible
via the code select key.
The vent position will display for 30 seconds whenever
motion corresponding to 5CMH (3CFM) or greater is
detected. It will scroll in intervals of 5CMH (3CFM).
Scrolling to Cd45 will display the Fresh Air Vent Position.
The position of the vent will be recorded in the
DataCORDER whenever the unit is running under AC
power and any of the following:
Trip start
On every power cycle
Midnight
Manual change greater than 5CMH (3CFM) and
remains in that position for four minutes
NOTE
The user has four minutes to make necessary
adjustments to the vent setting. This time calcu-
lation begins on the initial movement of the
sensor. The vent can be moved to any position
within the four minutes. On completion of the
first four minutes, the vent is required to remain
stable for the next four minutes. If vent position
changes are detected during the four
−
minute
stability period, an alarm will be generated. This
provides the user with the ability to change the
vent setting without generating multiple events
in the DataCORDER.
4.4 eAutoFresh OPERATION
The eAutoFresh system allows the opening and closing
of the mechanical air vent slide. The opening and
closing of the slide is determined by the mode selected
through Cd43.
The modes of operation are OFF, USER, TEST, DELAY,
and GASLIMIT. Each mode of operation has submenus
with selectable parameters. Not all parameters are
available in each submenu.
Upon power up, the controller will fully close the
eAutoFresh air vent. Nine seconds after power up, the
controller will check if there is a carbon dioxide (CO
2)
sensor connected. When a CO
2
sensor is detected, the
controller will enable access to the Gas Limit mode of
operation. If no sensor is detected, the only modes of
operation available will be Test, User, and Delay. The
controller will then resume operation in the last mode of
operation before power interruption.
4.4.1 eAutoFresh Pre
−
Trip Inspection
Pre
−
trip testing of the eAutoFresh system is performed
during Pre
−
Trip test P0. Operation of the system may be
observed during this test.
Upon initiation of Pre
−
Trip P0, the current state will be
saved and the vent will fully close. This will be followed
by two sequences of opening to 100% and returning to
the closed position. No other eAutoFresh mode of
operation will be available until the two cycles of opening
and closing have completed. Upon termination of the
test, the vent will open to the previous state and
operation will return to the previous mode.
If the last mode was gASLM, the vent will open to the
preset FLO setting, the controller will start taking new
readings and control based on those readings.
4.4.2 eAutoFresh Start
−
Up Procedure
To start the system, do the following:
a. Press the “CODE SELECT” key (see Figure 3-2).
b. Press the “UP or DOWN“ arrow key until “Cd43“ is
displayed, then press “ENTER”.
c. Press the “UP or DOWN“ arrow key to access the de-
sired mode of operation. When the mode operation is
displayed press the enter key to access the submenu
parameters.
4.4.3 eAutoFresh Modes of Operation
NOTE
When setting any mode of operation, complete
the entire process to ensure all parameters are
set.
a. OFF
A setting of OFF will disable all automatic venting
operations. The eAutoFresh vent will be driven fully
closed and the eAutoFresh opening set to 0 CMH in
Cd44. This is the default mode whenever a frozen mode
of operation has been selected. When the frozen set
point is selected, the current eAutoFresh setting is
saved. The vent position will restore when a perishable
set point is selected.
b. USER
The USER mode provides ventilation for commodities
that require fresh air circulation. The flow rate can be
accessed through the submenu if a perishable set point
has been selected. To set the flow rate, press the
ENTER key to activate the selection mode. When FLO
appears in the left hand window, use the UP or DOWN
arrow key to scroll to the desired opening. The range is
from 0 to 220CM (0 to 129CF) in increments of 5. Press
the ENTER key to set the value and begin operation.
c. TEST
TEST mode allows the operator to test the movement of
the mechanical slide air vent and calibrate the CO
2
sensor.
tESt
−
When “tESt” appears in the left window, press the
ENTER key to begin the test. The eAutoFresh slide will
open fully and then return to the closed position. The
test may be observed by the operator to ensure proper
operation of the vent. After completion of the TEST, the
unit will return to the previous mode of operation.
NOTE
It is recommended that the calibration proced-
ure only be performed during Pre
−
trip or when
the container has been fully vented.