Trane Tracer ZN524, Руководство по диагностике для владельца установки

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24 CNT-SVX11A-EN
Unit Operation
Power-Up
When 24 VAC is initially applied to the
controller, the following sequence of
events occurs:
• Green status LED turns on.
• All outputs are controlled
OFF
.
• The controller reads input values to
determine initial values.
• Random-start timer expires
(5 to 30 seconds).
• When
POWER
-
UP CONTROL WAIT
is
enabled, the controller waits 0-120
seconds (depending on configuration)
to allow ample time for
communicated control data to input. If
the controller does not receive
communi-cated information, stand
alone control is assumed.
• All valves and dampers are closed.
•
N
ORMAL
operation begins.
Occupancy
The valid occupancy modes for the
Tracer ZN524 controller are:
• O
CCUPIED
- Normal operating mode
for occupied spaces or daytime
operation.
• U
NOCCUPIED
- Normal operating mode
for unoccupied spaces or nighttime
operation.
• O
CCUPIED
S
TANDBY
- Mode used to
reduce the heating and cooling
demands during the occupied hours
when the space is vacant or is
unoccupied.
• O
CCUPIED
B
YPASS
-Used to
temporarily transition the unit from
unoccupied to occupied operation.
The occupancy mode can be hardwired
to the controller via the occupancy
binary input or communicated to the
controller.
O
CCUPIED
mode
When the controller is in the
OCCUPIED
mode, the unit attempts to maintain the
space temperature at the active occu-
pied heating or cooling setpoint.
O
CCUPIED
mode is the default mode of
the Tracer ZN524 controller.
U
NOCCUPIED
mode
When the controller is in the
UNOCCUPIED
mode, the unit attempts to
maintain space temperature at the
stored unoccupied heating or cooling
setpoint (i.e., configurable through
Tracer Summit or the Rover service
tool) regardless of the presence of a
hardwired or communicated setpoint.
When the space temperature exceeds
the stored unoccupied setpoint, the
controller brings on 100% of the pri-
mary heating or cooling capacity.
The
UNOCCUPIED
mode can be initiated
through a hardwired signal to the occu-
pancy binary input or by a communi-
cated request.
O
CCUPIED
S
TANDBY
mode
The
OCCUPIED STANDBY
mode allows the
unit to operate at a heating or cooling
setpoint between the occupied and
unoccupied setpoints to help maintain
the environment while decreasing ener-
gy consumption.
This mode can decrease the energy
consumption for heating or cooling
during brief periods of vacancy in the
space. Unit operation in this mode is
similar to the occupied mode except for
the different heating and cooling set-
points.
The
OCCUPIED STANDBY
mode is initiated
only when occupancy is communicated
to the Tracer ZN524 controller and the
hardwired signal to the occupancy
input is calling for unoccupied opera-
tion.
O
CCUPIED
B
YPASS
mode
The
OCCUPIED BYPASS
mode is used to
transition the unit from the
UNOCCUPIED
mode to the occupied mode for a peri-
od of time from 0 to 4 hours (config-
urable through Rover. Default=
2 HRS ).
The controller can be placed in
OCCUPIED BYPASS
mode by either com-
municating an occupancy request of
bypass or by using the
TIMED OVERRIDE
(i.e., ON ) button on the Trane zone sen-
sor.
O
N
and C
ANCEL
Buttons
Some Trane zone sensors have O
N
and
C
ANCEL
buttons for timed override
operation. Pressing the On button on
the zone sensor when the unit is in the
UNOCCUPIED
mode initiates the
OCCUPIED BYPASS
mode and initializes
the bypass timer. The cancel button is
used to send the unit back into
UNOCCUPIED
mode before the bypass
timer has expired.
The On button may also be used for the
unit identification or the
“WINK” fea-
ture. When the Tracer ZN524 controller
is connected to a Tracer Summit sys-
tem, Loop Controller, or the Rover serv-
ice tool, the On button may be used in
place of the service pin for easy unit
identification.
Heating And Cooling
Changeover Logic
The Tracer™ ZN524 Unit Controller can
receive communicated requests for
heating or cooling operation. The com-
municated variable nviApplicMode is
used to communicate the requests for
the controller's operating mode based
on the following values:
0 = Auto (mode determined by con-
troller)
1 = Heat (uses heating setpoints)
2 = Morning Warm-up
3 = Cool (uses cooling setpoints)
5 = Pre-cool (morning cool down)
6 = Off (no unit operation allowed)
7 = Test (special test mode)
9 = Fan Only (no heating or cooling)