Controls
CAB-PRC001-EN
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Control Features
The following control functions are
standard features on units with Tracer
ZN.010, ZN.510, or ZN.520.
Occupied/Unoccupied Operation
The occupancy input utilizes a binary
switch (i.e. motion sensor, timeclock, etc.)
that allows the zone sensor to utilize it’s
unoccupied internal setpoints.
Random Start
This feature randomly staggers multiple
unit start-up to reduce electrical demand
spikes.
Warm-up
The two-position fresh air damper option
closes during the occupied mode when
the space temperature is three degrees or
more below the heating setpoint tem-
perature. The damper remains closed
during warm-up until the space tempera-
ture is within two degrees of the heating
setpoint temperature.
Manual Output Test Function
This feature is an invaluable tool for
troubleshooting a unit. By simply
pressing the controller’s test button,
service personnel can manually exercise
outputs in a pre-defined sequence.
Peer to Peer Communication (ZN.510 and
ZN.520)
Peer to peer communication allows
multiple units in one space to share the
same zone sensor and provide simulta-
neous heating. The ZN.510 or ZN.520
controller can share information between
units on the same communication link
using a twisted pair wire in the field. Unit
Features
configuration must be modified with
Rover service tool.
ZN.520 Additional Features
Fan Status
The ZN.520 controller monitors the fan
output status to determine if the fan is
operating.
Filter Maintenance Status
The controller has an adjustable timer
that indicates through Summit or Rover
when filter maintenance is necessary.
Filter maintenance status is based on
cumulative fan run hours.
Water Valve Override
Using Summit or Rover, the water valve
override function drives all water valves
in every unit fully open simultaneously.
This helps reduce the time required for
waterside balancing.
Cascade Control
The controller maintains discharge air
temperature using a cascade control
algorithm. The discharge air temperature
is based on the difference between the
space temperature and setpoint. Unit
capacity modulates to achieve the
discharge air temperature.
Interoperability
The ZN.520 controller can be used with a
Tracer Summit system or on other
control systems that suport LonTalk and
the SCC profile. For more information on
specific inputs and outputs, see the
Installation, Owner, and Maintenance
Manual, UNT-IOM-6.
