York YPAL 050, YPAL 061, YPAL 051 Power Wiring, Overcurrent Protection Device Data is supplied on

FORM 100.50-NOM6 (1207)

POWER WIRING

POWER WIRING

Field wiring to the unit must conform to provisions of National Electrical Code (NEC) ANSI / NFPA 70- Latest Edition and / or local ordinances. The unit must be electrically grounded in accordance with the NEC and / or local codes. Voltage tolerances, which must be maintained during starting and running conditions, are indicated on the unit data plate.

The internal wiring harnesses furnished with this unit are an integral part of the design certified unit. Field alteration to comply with electrical codes should not be required. If any of the wire supplied with the unit must be replaced, replacement wire must be of the type shown on the wiring diagram and the same minimum gauge as the replaced wire.

Power supply to the unit must be NEC Class 1 and must comply with all applicable codes. A disconnect switch must be provided (factory option available). The switch must be separate from all other circuits. Wire entry at knockout openings requires conduit fittings to comply with NEC and/or Local Codes.

Refer to Figures 2-9, 2-10 & 2-11 for typical field wiring andtotheappropriateunitwiringdiagrammountedinside control doors for control circuit and power wiring information.

ELECTRICAL SERVICE SIZING

Electrical service required for the cooling only eco2 rooftop, use the appropriate calculations listed below from U.L. 1995. Based on the operating mode and configuration of the rooftop, the calculations will yield different MCA (minimum circuit ampacity), and MOP (maximum overcurrent protection). MCA and

Overcurrent Protection Device Data is supplied on

the unit data plate. Also refer to Table 2-7, 2-9, 2-10, 2-11, 2-12, 2-13 and 2-14, Electrical Data.

The following calculations apply to electrical data for the rooftop unit. All concurrent load conditions must be considered in the calculations, and you must use the highest value for any combination of loads.

Minimum CircuitAmpacity (MCA) is based on 125% 2

of the rated load amps for the largest motor plus 100% of the rated load amps for all other loads included in the circuit, per N.E.C. Article 440-34.

The minimum recommended disconnect switch is based on 115% of the rated load amps for all loads included in the circuit, per N.E.C.

Maximum overcurrent protection is based upon 225% of the rated load amps for the largest motor plus 100% of the rated load amps for all other loads included in the circuit, per N.E.C. Article 440-22. If the maximum overcurrent protection does not equal a standard current rating of an overcurrent protective device, then the marked maximum rating is to be the next lower standard rating. However, if the device selected for maximum overcurrent protection is less than the MCA, then select the lowest standard maximum fuse size greater than or equal to the MCA.

Figures 2-9, 2-10 & 2-11 show the power wiring that must be field supplied and installed. See Table 2-16 for the allowable conductor wire size for the electrical lugs in the unit.

For dual point power connections, TB1 in the power panel supplies the all unit compressors and condenser fans. TB2 in the power panel supplies power to the unit supply, return and exhaust fans, and control circuitry.

All wiring must conform to the Na- tional Electrical Code (NEC) and local codes that may be in addition to NEC.

JOHNSON CONTROLS 37