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Option 18 — Backlight Configuration
When OF (off), the backlight will be lit for 10 seconds after a button is pressed.
After 10 seconds of no button presses, the backlight turns off. When On, the
backlight will normally be on and dim in appearance. The backlight brightness
becomes brighter when a button is pressed. After 10 seconds of no button
presses, the backlight will return to the dimmer level until another button press
occurs. The range of brightness is 1 through 5 with 5 being full brightness.
Default is 3.
Option 19 — Dry Contact Configuration (programmable models only)
There are 3 available selections, OF, 1 and 2.
OF — The dry contact is always de
−
energized.
1 — The dry contact will be energized for the specified number of minutes per
hour. This selection is programmable by period. When this selection is changed
from OF to 1, the period icons are shown and the minute segments of the clock
display are shown. The triangle icon next to the WAKE period will be on and a
value between 0 and 60 will be shown in the minutes display. See Operational
Information and Wiring Diagrams for further explanation of dry contact
configuration and use. To change the period or minutes, press the soft key below
the period or minutes and then use the UP/DOWN buttons to change to the
desired value.
2 — The dry contact will operate as a DH relay. This relay is reverse logic. When
the humidity level is above the dehumidify setpoint, the dry contact D1
−
D2 will
be opened. When the humidity level is below the dehumidify setpoint, D1
−
D2
will be closed. There is a +/
−
2% hysteresis around the dehumidify setpoint to
prevent rapid on/off cycling of the DH output. When configured for
dehumidification, the Rc terminal must be connected to one of the dry contact
terminals. This provides power to energize the dehumidify terminal on the