York MILLENIUM YCAS Series, Установка, эксплуатация и обслуживание, Страница: 31 / 156

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YORK INTERNATIONAL
FORM 201.18-NM6
If the ducts from two or more fans are to be combined
into a common duct, back-flow dampers should be fit-
ted in the individual fan ducts. This will prevent recircu-
lation of air when only one of the fans is running.
Units are supplied with outlet guards for safety and to
prevent damage to the fan blades. If these guards are
removed to fit ductwork, adequate alternative precau-
tions must be taken to ensure persons cannot be harmed
or put at risk from rotating fan blades.
ELECTRICAL CONNECTION
The following connection recommendations are intended
to ensure safe and satisfactory operation of the unit.
Failure to follow these recommendations could cause
harm to persons, or damage to the unit, and may invali-
date the warranty.
No additional controls (relays, etc.)
should be mounted in the control
panel. Power and control wiring not
connected to the control panel should
not be run through the control panel.
If these precautions are not followed
it could lead to a risk of electrocution.
In addition, electrical noise could
cause malfunctions or damage the
unit and its controls.
After connection do not switch on
mains power to the unit. Some inter-
nal components are live when mains
is switched on and this must only be
done by Authorized persons.
POWER WIRING
All electrical wiring should be carried out in accordance
with local regulations. Route properly sized cables to
cable entries on both sides of the unit.
In accordance with U.L. Standard it is the responsibil-
ity of the user to install overcurrent protection devices
between the supply conductors and the power supply
terminals on the unit.
To ensure that no eddy currents are set up in the power
panel, the cables forming each 3-phase power supply
must enter via the same cable entry.
All sources of supply to the unit must
be taken via a common point of isola-
tion (not supplied by YORK).
STANDARD UNITS WITH MULTI POINT POWER
SUPPLY WIRING
Standard units require two 3-phase separately fused 3-
wire supplies plus a ground per refrigerant system. One
supply to be connected to each of the power panels.
Connect each of the main 3-phase supplies to the cir-
cuit breakers, non-fused disconnect switches or termi-
nal boards located in the power panels using lug sizes
detailed in the Technical Data Section.
Connect the ground wires to the main protective ground
terminals in each power panel.
Units with Single-Point Power Supply Wiring
Units require only one 3-phase plus ground.
Connect the 3-phase supplies to the terminal block or
non-fused disconnect switch located in the options panel
using lug sizes detailed in the Technical Data Section.
Connect a ground wire to the main protective ground
terminal.
115VAC CONTROL SUPPLY TRANSFORMER
A 3-wire high voltage to 115VAC supply transformer is
standard in the chiller. This transformer is mounted in
the Options Cabinet and steps down the high voltage
supply to 115VAC to be used by the Micro Panel, Power
Panel components, solenoids, heaters, etc.
The high voltage for the transformer primary is taken
from the chiller input to one of the systems. Fusing is
provided for the transformer.
It is important to check that the cor-
rect primary tapping has been used
and that it conforms to the site high
voltage supply.
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