General Information
PKG-SVP01E-EN
7
At power-up, the Human Interface LCD will display one of
four initial screens illustrated in the “General Status”
section.
1.
Unit Status (Unit Off or Stopped) (The unit is
configured and operational, but is not running). This
screen shows state, mode, and function information
when the unit is off or stopped.
2. Unit Status (Unit On) (The unit is configured and
operational, and is running).This screen shows state,
mode, and function information when the unit is on.
3. VOM Active (a ventilation override command was
received) This screen shows that the unit is in a
Ventilation Override Mode.
4. No Configuration (the unit needs to be configured).
This screen shows that required configuration data is
missing.
The LCD screen has a backlight that makes the information
easier to read.The light will go out if no keys are pressed
for 30 minutes. If it goes out, simply press the STATUS key.
Ventilation Override Module (VOM) Definitions
The ventilation override module can be field-configured
with up to five different override sequences for ventilation
override control purpose. When any one of the module’s
five binary inputs are activated, it will initiate specified
functions such as; space pressurization, exhaust, purge,
purge with duct pressure control, and unit off.
Once the ventilation sequences are configured, they can
be changed unless they are locked using the HI. Once
locked, the ventilation sequences cannot be unlocked.
The compressors and condenser fans disable during the
ventilation operation. If more than one ventilation
sequence activates, the one with the highest priority (VOM
“A”) begins first, with VOM “E” having lowest priority and
beginning last.
A description of the VOM binary inputs follows below.
UNIT OFF sequence “A”
When complete system shut down is required, the
following sequence can be used.
•
Supply fan – Off
•
Supply fan VFD – Off (0 Hz) (if equipped)
•
Inlet guide vanes – closed (if equipped)
•
Outside air dampers – Closed
•
Heat – all stages – Off, Modulating heat output at 0 vdc
•
Occupied/Unoccupied output – Deenergized
•
VO relay – Energized
•
Exhaust fan (field-installed) - Off
•
Exhaust damper (field-installed) - Closed
PRESSURIZE sequence “B”
This override sequence can be used if a positively
pressured space is desired instead of a negatively
pressurized space.
•
Supply fan – on
•
Supply fan VFD – on (60 Hz) (if equipped)
•
Inlet guide vanes/VAV boxes – open (if equipped)
•
Outside air dampers – open
•
Heat – all stages – off, hydronic heat output at 0 vdc
•
Occupied/ unoccupied output - energized
•
VO relay - energized
•
Exhaust fan (field-installed) - off
•
Exhaust damper (field-installed) - closed
EXHAUST sequence “C”
With the building’s exhaust fans running and the unit’s
supply fan off, the conditioned space becomes negatively
pressurized. This is desirable for clearing the area of
smoke when necessary; i.e. from an extinguished fire, to
keep smoke out of areas that were not damaged.
•
Supply fan – off
•
Supply fan VFD – off (0 Hz) (if equipped)
•
Inlet guide vanes – closed (if equipped)
•
Outside air dampers – closed
•
Heat – all stages – Off, hydronic heat output at 0 vdc
•
Occupied/Unoccupied output – deenergized
•
VO relay – energized
•
Exhaust fan (field-installed) - on
•
Exhaust damper (field-installed) - open
PURGE sequence “D”
This sequence could be used for purging the air out of a
building before coming out of unoccupied mode of
operation on VAV units. Also, it can be used to purge
smoke or stale air.
•
Supply fan – on
•
Supply fan VFD – on (60 Hz) (if equipped)
•
Inlet guide vanes/VAV boxes – Open (if equipped)
•
Outside air damper – Open
•
Heat – all stages – Off, Modulating heat output at 0 vdc
•
Occupied/Unoccupied output – Energized
•
VO relay – Energized
•
Exhaust fan (field-installed) - On
•
Exhaust damper (field-installed) - Open
