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T-318
3
−
26
Table 3-5 Controller Function Codes (Sheet 7 of 9)
Code
No.
TITLE
DESCRIPTION
Cd48
Dehumidification /
Bulb Cargo Mode
Parameter Selection
Initially Cd48 will display current dehumidification
−
mode; bUlb
−
bulb cargo mode,
dEhUM
−
normal dehumidification, or OFF
−
off. This display is steady.
Pressing ENTER key will take the interface down into a hierarchy of parameter
selection menus (mode, setpoint, evaporator speed, DTT setting). Pressing
ENTER key in any parameter selection menu commits to selection of the
currently displayed parameter and causes the interface to descend into the next
parameter selection menu. All parameter selection menus alternate between a
blank display and the current selection in the right hand display.
Pressing CODE SELECT key in a selection menu cancels the current selection
activity and ascends back up to the next higher selection menu (or to Cd48
display mode if that is the next higher).
If the operator does not press any key for five seconds the interface reverts to
normal system display and the current selection menu is cancelled, but any
previously committed changes are retained.
Available parameters and parameter ranges are a function of configuration
options and previously selected parameters as indicated above.
Whenever any pretrip test is initiated, dehumidification
−
mode goes to OFF.
Whenever dehumidification
−
mode goes to OFF:
−
Dehumidification control setpoint goes to 0% RH internally but will then initialize to
95% RH when dehumidification
−
mode leaves OFF.
−
Evaporator speed select goes to Alt for units without PWM Compressor Control
(Cnf57 = Out), Evaporator speed select goes to Hi for units with PWM
Compressor Control (Cnf57 = In).
−
DTT setting goes to 25.6
C or 18.0
C, depending on Cnf41.
Whenever dehumidification
−
mode is set to bUlb, DTT setting goes to 18.0
C if it
had been set higher.
Whenever dehumidification
−
mode is set to dEhUM, DTT setting goes to 25.6
C
or 18.0
C, depending on Cnf41.
For units without PWM Compressor Control (Cnf57 = Out):
−
Whenever dehumidification control setpoint is set below 65% RH evaporator
speed select goes to LO if it had been set to Hi.
−
Whenever dehumidification control setpoint is set above 64% RH evaporator
speed select goes to Alt if it had been set to LO.
For units with PWM Compressor Control (Cnf57 = In):
−
Whenever dehumidification control set point is set below 60% RH, the evaporator
fan speed is set to LO, the user has the ability to set the evaporator fan speed to Hi
via the keypad.
−
Whenever dehumidification control set point is set equal to or above 60% RH, the
evaporator fan speed is set to Hi, the user has the ability to set the evaporator fan
speed to LO via the keypad.
Display Only Function
−
Cd49 is a display only function.
Cd49 Days Since Last
Successful Pre-trip
Displays the number of days since last successful pretrip sequence.
Press ENTER to view the number of days since the last successful pretrip for
Auto1, Auto2, and Auto2 in sequence.
Press CODE SELECT to step back through the list and ultimately to exit the
Cd49 display.