York YCAS0130 - Manual (Page 34)

34 YORK INTERNATIONAL
FORM 201.19-NM1 (204)
If the ducts from two or more fans are to be combined
into a common duct, back-fl ow dampers should be fi t-
ted in the individual fan ducts. This will prevent re cir -
cu la tion 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 re-
moved to fi t ductwork, adequate alternative pre cau tions
must be taken to ensure persons cannot be harmed or
put at risk from rotating fan blades.
ELECTRICAL CONNECTION
The following connection rec om men da tions are in-
tend ed to ensure safe and sat is fac to ry operation of the
unit. Failure to follow these recommendations could
cause harm to persons, or damage to the unit, and may
in val i date the warranty.
No additional controls (re lays, etc.)
should be mount ed in the control
pan el. Power and con trol wiring not
con nect ed to the con trol pan el should
not be run through the control pan el.
If these pre cau tions are not fol lowed it
could lead to a risk of elec tro cu tion. In
ad di tion, elec tri cal noise could cause
mal func tions or dam age the unit and
its con trols.
After connection do not switch on
main pow er to the unit. Some in ter nal
com po nents are live when main power
is switched on and this must only be
done by Au tho rized persons.
POWER WIRING
All electrical wiring should be carried out in ac cor dance
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 re spon si bil i ty
of the user to install overcurrent pro tec tion devices
be tween the supply con duc tors and the power supply
ter mi nals 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 iso-
la tion (not sup plied by YORK).
STANDARD UNITS WITH MULTI POINT POWER
SUPPLY WIRING
Standard units require two 3-phase sep a rate ly fused 3-
wire supplies plus a ground per re frig er ant 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 ter mi nal
boards located in the power panels using lug sizes de-
tailed 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 supply plus ground.
Connect the 3-phase supplies to the terminal block or
non-fused disconnect switch/circuit breaker located in
the options pan el using lug sizes detailed in the Techni-
cal 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 steps down
the high voltage supply to 115VAC to be used by the
Micro Panel, Pow er Pan el com po nents, so le noids, heat-
ers, etc.
The high voltage for the transformer pri ma ry is taken
from the chiller input to one of the sys tems. Fusing is
provided for the trans form er.
It is important to check that the cor-
rect primary tap ping has been used
and that it con forms to the site high
volt age sup ply.
Installation