Installation Instructions

Special Features
System Level Occupancy Control
Occupancy for an air handler should be coordinated with occupancy for its respective zones. A
site may employ more than one of the following interoperation mechanisms to accomplish system
level coordination:
• The Predator Air Handler Controller may drive occupancy of the zones through bound
network variables.
• The zone controllers may drive occupancy of the air handler so that it runs to meet their
needs.
• Occupancy of the zones and air handler may both be driven in a coordinated way by
another LonMark device.
The Predator responds to LonMark occupancy override (nviOccManCmd), allowing a building
operator or technician to override the system from any LonMark compatible user interface.
The Predator responds to a LonMark compatible occupancy schedule input (nviOccSchedule).
This allows the Predator to utilize the scheduling functions of other devices on the LonTalk
Network.
The primary occupancy signal could also come from a time clock, wall switch, or occupancy
sensor physically wired to one of the inputs of the Predator. This occupancy signal can then be
shared with other controllers via the LonTalk Network.
Duct Pressure Reset
To comply with ASHRAE Standard 90.1, Energy Efficiency for Commercial Buildings, the
Predator supports automatic duct pressure reset by accepting a variable setpoint. The
dynamic setpoint may calculated according to any algorithm in another device, and transmitted
over the network.
Supply Temperature Reset
The Predator can run an air handler as a classic constant-temperature VAV system, or it can
dynamically adjust the supply temperature to adapt to loading conditions. The temperature
may be reset using a built-in adjustable reset schedule, or calculated externally with a custom
algorithm, and transmitted via the LonWorks network. The built-in reset schedules directly
support the most popular approaches: reset based on space temperature, return temperature,
outdoor temperature or a selected percentage demand signal from the zone controllers.
Demand Controlled Ventilation
The Predator can control ventilation by the industry standard approach, using an adjustable
minimum OA damper opening or by a demand-controlled strategy that adjusts the OA intake
according to IAQ measurements in the occupied spaces. The DCV lets an HVAC designer
build the system for the maximum anticipated ventilation requirements, but operate the system
more economical ventilation rates when the actual demand is lower.
Night Heating and Cooling
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Document No. 588-150
The Predator supports several heating and cooling options for unoccupied periods.
Using zone temperature data that either comes from the directly connected zone sensor
or delivered over the network, the controller can cycle the air handler to meet heating
and cooling needs of the zones. This function requires no intervention from a
supervisory node. If some other start/stop criteria is required, another node may
implement that logic and command the air handler on and off during the unoccupied
period.