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The high static option supply fan motor is equipped with a pi
-
lot-circuit Thermix combination over-temperature/over-current
protection device. This device resets automatically. Do not by
-
pass this switch to correct trouble. Determine the cause and
correct it.
CONDENSER FAN MOTOR PROTECTION
The condenser fan motor is internally protected against over-
temperature.
Relief Device
A soft solder joint at the suction service access port provides
pressure relief under abnormal temperature and pressure condi
-
tions (i.e., fire in building). Protect this joint during brazing op
-
erations near this joint.
Control Circuit, 24-V
The control circuit is protected against overcurrent conditions
by a circuit breaker mounted on control transformer TRAN.
Reset is manual.
SYSTEMVU CONTROL SYSTEM
The SystemVu™ control is a comprehensive unit-management
system. The control system is easy to access, configure, diag
-
nose and troubleshoot.
The SystemVu control system is fully communicating and
cable-ready for connection to the Carrier Comfort Network
®
(CCN), Carrier i-Vu
®
, and Third Party BACnet
1
building man
-
agement systems. The control provides high-speed communi
-
cations for remote monitoring via the Internet. Multiple units
can be linked together (and to other Direct Digital Control
(DDC) equipped units) using a 3-wire communication bus.
The SystemVu control system is easy to access through the use
of a integrated display module. A computer is not required for
start-up. Access to control menus is simplified by the ability to
quickly select from 7 main menu items. An expanded readout
provides detailed explanations of control information. Only six
buttons are required to maneuver through the entire controls
menu. The display readout is designed to be visible even in
bright sunlight. See Fig. 47.
SystemVu Interface
This integrated device is the keypad interface used to access
the control information, read sensor values, and test the unit.
The interface is located in the main control box.
Through the SystemVu interface, the user can access all of the
inputs and outputs to check on their values and status, config
-
ure operating parameters, and evaluate the current decision sta
-
tus for operating modes. The control also includes an alarm
history which can be accessed from the display. The user can
access a built-in test routine that can be used at start-up com
-
missioning and troubleshooting.
Air Temperature Sensors
The SystemVu controller uses thermistors to sense tempera
-
tures used to control operation of the unit. Air temperatures are
measured with 10k thermistors. This includes supply-air tem
-
perature (SAT), outdoor-air temperature (OAT) and return-air
temperature (RAT) sensors. See Fig. 48 for location of these
sensors.
Additional SystemVu Installation and Trouble-
shooting
Additional installation, wiring and troubleshooting information
for the SystemVu Controller can be found in the following
manual: 48/50JC 04-06 Ultra High Efficiency Single Package
Rooftop Units with SystemVu™ Controls Version X.X Con
-
trols, Start-up, Operation and Troubleshooting Instructions.
Fig. 47 —
SystemVu Control
1. BACnet is a trademark of ASHRAE.
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