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OM 750
Table 7. UVC State Names and Numbers (see figure 6)
State
State
Normal UVC Modes
Numbers
Names
(ASCII)
Off
Off
9(57)
Night Purge
Night Purge
8(56)
Fan Only
Fan Only
A(65)
Emergency Heat
Full Heat
7(55)
Super State
Cant Heat
D(68)
Heat
5(53)
Heat
Cant Heat
B(66)
Super State
Low Limit
E(69)
EconMech
1(49)
Auto
Mech
2(50)
Cool
Econ
3(51)
Super State
DA Heat
4(52)
Cant Cool
C(67)
Low Limit
F(70)
Dehumidify
햲
Active Dehum
6 (54)
햲
Optional.
UVC Unit Modes
The UVC provides several “normal” modes of unit operation, these
include Off, Night Purge, Fan Only, Cool, Emergency Heat, Auto,
Heat and Cool.
Normal UVC modes can contain a single state or several states
dependent upon the functionality required for each particular mode.
Each UVC state has been assigned a number. This state number can be
very helpful when trying to understand which state is currently active
within the UVC. The current UVC state number can be viewed using
the LUI. See Figure 6 for Super State and State.
Transition
(UVC Mode = Off)
into State
Operation
When Off mode becomes active, the UVC stops all
within State
normal heating, cooling, ventilation (OA damper is
closed), and fan operation. The UVC will continue to
monitor space conditions, indicate faults, and provide
network communications (if connected to a network)
as long as power is maintained to the unit. If the space
temperature drops below EHS, and the Emergency
Heat function is enabled, the UVC will be forced into
the Emergency Heat mode (see Emergency Heat Mode).
The space lighting output will continue to operate
normally based upon the current UVC occupancy
mode.
Special purpose unit modes (i.e. Purge, Pressurize,
and De-pressurize modes) accessed via a network
connection can force the UVC to perform “special”
functions during which the UVC will appear to be in
the Off mode. See Special Purpose Unit Modes, and
the UVC Unit Mode Priority sections for more
information.
The UVC will remain in this state until one of the
transition out conditions become true.
Transition
(UVC Mode
≠
Off)
out of State
Figure 7. Off State Diagram
OFF MODE (STATE NUMBER 9)
Off mode is provided so that the UVC can be forced into a powered off
condition. The Off mode is a “stop” state for the unit ventilator, it is not
a power off state. The LUI or a network connection can force the unit
into the Off mode. Off mode consists of a single UVC state: Off [9].
WARNING
!
Off mode is a “stop” state for the unit ventilator. It is not a “power
off” state. Power may still be provided to the unit.
NIGHT PURGE MODE (STATE NUMBER 8)
Night Purge mode is provided as a means to more easily and quickly
ventilate a space. Night purge can be useful in helping to remove odor
build up at the end of each day, or after cleaning, painting, or other odor
generating operations occur within the space. Night Purge is a full
ventilation with exhaust mode, during which room comfort will very
likely be compromised, it is therefore strongly recommended that
Night Purge only be used when the space is unoccupied. The LUI or a
network connection can force the unit into the Night Purge mode. Night
Purge mode consists of a single UVC state: Night Purge [8].
Transition
(UVC Mode = Night Purge)
into State
Operation
When Night Purge mode becomes active, the UVC
within State
stops all normal heating and cooling as any new energy
used to treat the incoming air would be wasted in the
Figure 8. Night Purge State Diagram