Daikin DPSA Manual page 34

F. Propeller Exhaust Fan
1. Direct-drive axial exhaust fans shall be provided.
Blades shall be constructed with fabricated steel
and shall be securely attached to fan shafts. All
exhaust fan assemblies shall be statically and
dynamically balanced. Totally enclosed motors
shall be permanently lubricated, heavy-duty type,
carefully matched to the fan load. Ground and
polished steel fan shafts shall be mounted in
permanently lubricated and sealed ball bearings.
Bearings shall be selected for a minimum (L10)
life in excess of 100,000 hours at maximum
cataloged operating speeds.
2. The unit DDC controller shall provide building
static pressure control. A factory mounted
exhaust fan variable frequency drive shall
provide proportional control of the exhaust fans
from 25% to 100% of the scheduled exhaust air
fan designed airflow and ESP. The field shall
mount the required sensing tubing from the
building to the factory mounted building static
pressure sensor.
H. ECM Exhaust Fan
1. All fans shall be a single width, single inlet
(SWSI) airfoil centrifugal fan. The fan wheel
shall be Class II construction with aluminum
fan blades that are continuously welded to the
hub plate and end rim. The fan shall be a direct
drive fan mounted to the motor shaft. Belts and
sheaves are not acceptable due to the additional
maintenance.
2. The fan motor shall be a totally enclosed
electrically commutated motor that is speed
controlled by the rooftop unit controller. The
motor shall include thermal overload protection
and protect the motor in the case of excessive
motor temperatures. The motor shall have phase
failure protection and prevent the motor from
operation in the event of a loss of phase. Motors
shall be premium efficiency.
I. ECM Return Fans.
1. All fans shall be a single width, single inlet
(SWSI) airfoil centrifugal fan. The fan wheel
shall be Class II construction with aluminum
fan blades that are continuously welded to the
hub plate and end rim. The fan shall be a direct
drive fan mounted to the motor shaft. Belts and
sheaves are not acceptable due to the additional
maintenance.
2. The fan motor shall be a totally enclosed
electrically commutated motor that is speed
controlled by the rooftop unit controller. The
motor shall include thermal overload protection
and protect the motor in the case of excessive
motor temperatures. The motor shall have phase
failure protection and prevent the motor from
operation in the event of a loss of phase. Motors
shall be premium efficiency.
3. Exhaust Fan configurations are not allowed as
alternate
CAT 258 • REBEL APPLIED ROOFTOP
2 .06 Electrical
A. Unit wiring shall comply with NEC requirements
and with all applicable UL standards. All electrical
components shall be UL recognized where
applicable. All wiring and electrical components
provided with unit shall be number and color coded
and labeled according to the electrical diagram
provided for easy identification.
B. The unit shall be provided with a factory wired
weatherproof control panel. Unit shall have a power
terminal block for main power connection. A terminal
board shall be provided for low voltage control
wiring. Branch circuit short circuit protection, 115
volt control circuit transformer and fuse, system
switches, and a high temperature sensor. Each
compressor and condenser fan motor shall be
furnished with contactors and inherent thermal
overload protection. Supply and return fan motors
shall have contactors and external overload
protection. Knockouts shall be provided in the of the
main control panels for field wiring entrance.
C. All 115-600 volt internal and external wiring between
control boxes and components shall be protected
from damage by dedicated electrical raceways.
D. The receptacle shall be powered by a field supplied
115V source.
E. The receptacle shall be powered by a factory
supplied 115V transformer and will be available
when the disconnect is in the OFF position.
F. Single non-fused disconnect swtich shall be
provided for connecting electrical power at the unit.
Disconnect switches shall be mounted internal to the
control panel and operated by an externally mounted
handle.
G. Unit SCCR Rating to be 10 kAIC minimum
H. Unit SCCR Rating to be 22 kAIC. minimum
I. Unit SCCR Rating to be 65 kAIC. minimum
J. Unit shall be provided with phase, voltage and
brown out protection which shuts down all motors in
the unit if the electrical phases are more than 10%
out of balance on voltage or on phase reversal.
K. A dual non-fused disconnect switchs shall be
provided for connecting two power sources to the
unit. Each disconnect switch shall be mounted
internal to the control panel and operated by an
externally mounted handle. Circuit 1 shall have the
compressors, condenser fan, and electric heat (if
present); Circuit 2 shall have the supply, return,
exhaust fans, controls, and gas heat if present.
L. Unit shall be provided with a safety shutdown
terminal for installation of field emergency input.
M. All electrical options shall have a +/- 10 percent
voltage utilization range to protect against voltage
variation.
34
General Specification
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