Installation

FORM 201.19-NM1 (204)

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 recir- culation 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 fit ductwork, adequate alternative precautions must be taken to ensure persons cannot be harmed or put at risk from rotating fan blades.

ELECTRICAL CONNECTION

The following connection recommendations are in- tended 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 invalidate 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 main power to the unit. Some internal components are live when main power 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 responsibility 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 iso- lation (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 terminal 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 panel 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, Power Panel components, solenoids, heat- ers, 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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YORK INTERNATIONAL

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York YCAS0130 manual Units with Single-Point Power Supply Wiring