Microprocessor Controller for MUA
6
®
-
Cycle:
The supply fan and heating will cycle on
when space temperature falls below the room
temperature setpoint minus differential. The supply
temperature setpoint will be set to the supply max
reset limit. The unit cycles off when the space
temperature reaches the unoccupied heating
setpoint.
-
Off:
The unit shall be disabled.
•
Summer Mode:
In the summer mode the unit
can be configured to operate continuously, or can
be disabled (adjustable for both occupied and
unoccupied modes). If equipped with modulating
OA and recirculated air dampers, the dampers shall
be positioned to the summer setpoint (adjustable for
both occupied and unoccupied modes).
-
Continuous:
The supply fan shall run continuously
for ventilation. Heating will be locked out.
-
Off:
The unit shall be disabled.
•
Exhaust Relief Contact:
A dry contact can be
configured to signal an exhaust fan to start or a relief
damper to open when the supply fan is running. This
can be configured to be enabled always (default),
occupied mode only, unoccupied mode only, or
never (this is adjustable for both summer and winter
modes).
Alarms
The microprocessor controller monitors alarms and will
alarm on the following conditions:
•
Dirty Filter Alarm:
If the outside air or return air
filter differential pressure rises above the differential
pressure switch setpoint, the microprocessor
controller will activate an alarm.
•
Supply and Exhaust Air Proving Alarm:
Microprocessor controller monitors fan proving on
each blower and displays an alarm in case of blower
failure.
• Supply Air Flow Limit:
If the supply air temperature
drops below supply air low limits (35°F), the controller
disables the unit and actives the alarm after preset
time delay (300/ Sec).
•
Sensor Alarm:
Microprocessor controller will send
an alarm if a failed sensor is detected (temperature,
pressure, relative humidity).
•
Other Alarms:
High/Low Refrigerant Pressure
•
Space Static Pressure:
The OA/RA dampers will
modulate based upon the signal from a building static
pressure sensor. The controller will modulate the
dampers, between the min and max OA positions,
based upon a comparison of the building static
pressure setpoint to the actual building static pressure
level reported from the sensor.
•
0-10 by Others:
An external field supplied 0-10 VDC
signal is responsible for setting the damper position.
•
Two Position:
An external field supplied digital
contact is responsible for setting the damper to max
position. The OA Damper min (30%) and max (100%)
positions are used for the low and high position
settings.
Heating and Ventilating Mode
This mode is an alternative sequence of operation
designed for heating and ventilating applications.
Heating and ventilating mode has 2 modes of operation,
summer mode and winter mode.
•
Changeover:
The microprocessor controller switches
between summer and winter mode automatically
(auto-changeover) or it can be commanded locally or
by the BMS (if equipped).
-
Auto-changeover (default):
The microprocessor
shall switch to winter mode when the space
temperature is below the change-over temp (65F°
adj). When space temperature rises above the
change-over temp + differential (65°F + 15°F adj),
the microprocessor shall switch to summer mode.
-
Manual:
The user will command the unit into
summer or winter mode using the keypad or
through the BMS (if equipped).
-
Summer lockout:
Summer mode will be locked
out and the unit will be locked into winter mode
if the outside air temperature falls below the
summer outdoor lockout setpoint (55°F adj).
•
Winter Mode:
In the winter mode the unit can be
configured to operate continuously, cycle on a call
for heating or can be disabled (adjustable for both
occupied and unoccupied modes). If equipped with
modulating OA and recirculated air dampers, the
dampers shall be positioned to the winter setpoint
(adjustable for both occupied and unoccupied
modes).
-
Continuous:
The supply fan shall run continuously
for ventilation. Heating will be enabled when
the outside air temperature is above the heating
lockout setpoint. The heating device will modulate
to maintain the supply temperature setpoint.
The supply temperature setpoint is reset by
space temperature (see section Setpoint Control
(Occupied)).
Sequence of Operation
Содержание PGD1000W00
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