Electrical Notes - York Millennium YCAS Series Installation Operation & Maintenance

NOTES (pages 50-52)
1. MRA is Maximum Running Amps, the maximum continuous current at any operating point in the rating range. Also referred to as MCA,
or Minimum Circuit Ampacity to be provided by the installer. If a factory mounted Control Transformer is provided, add 3 amps to the
system #1 MCA values in the YCAS Tables.
2. The recommended disconnect switch is based on a minimum of 115% of the summation rated load amps of all the loads included in the
circuit, per N.E.C. 440 - 12A1.
3. Minimum recommended fuse size is based on 150% of the largest motor RLA plus 100% of the remaining RLAs (U.L. Standard 1995,
Section 36.1). Minimum fuse rating = (1.5 x largest compressor RLA) + other compressor RLAs + (# fans x each fan motor FLA).
4. Maximum dual element fuse size is based on 225% maximum plus 100% of the rated load amps for all other loads included in the
circuit, per N.E.C. 440-22. Maximum fuse rating = (2.25 x largest compressor RLA) + other compressor RLAs + (# fans x each fan
motor FLA).
5. Minimum recommended circuit breaker is 150% maximum plus 100% of rated load amps included in the circuit, per circuit per U.L.
1995 Fig. 36.2. Minimum circuit breaker rating = (1.5 x largest compressor RLA) + other compressor RLAs + (# fans x each fan motor
FLA).
6. Maximum circuit breaker is based on 225% maximum plus 100% of the rated load amps for all loads included in the circuit, per circuit,
per U.L. 1995 Fig. 36.2. Maximum circuit breaker rating = (2.25 x largest compressor RLA) + other compressor RLAs + ( # fans x each
fan motor FLA).
7. The Incoming Wire Range is the minimum and maximum wire size that can be accommodated by unit wiring lugs. The (1), (2), or (3)
indicate the number of termination points or lugs which are available per phase. Actual wire size and number of wires per phase must
be determined based on ampacity and job requirements using N.E.C. wire sizing information. The above recommendations are based
on the National Electrical Code and using copper conductors only. Field wiring must also comply with local codes.
8. A ground lug is provided for each compressor system to accommodate field grounding conductor per N.E.C. Article 250-54. A control
circuit grounding lug is also supplied. Incoming ground wire range is #6 - 350 MCM.
9. The field supplied disconnect is a "Disconnecting Means" as defined in N.E.C. 100.B, and is intended for isolating the unit from the
available power supply to perform maintenance and troubleshooting. This disconnect is not intended to be a Load Break Device.
10. Two-Compressor machines with single-point power connection, and equipped with Star (Wye)-Delta Compressor motor start must also
include factory-provided individual system circuit breakers in each motor control center. All 3 & 4 Compressor machines equipped with
Star-Delta compressor motor start must also include factory-provided individual system circuit breakers in each motor control center.
11. Consult factory for Electrical Data on units equipped with "High Static Fan" Option. 50 Hz Fans are 3.5 kW each.
12. FLA for each "Low Noise Fan" motor is 4.1A.
13. Group Rated Breaker must be HACR type for cU.L. machines.
UNIT MTD SERV SW
YORK INTERNATIONAL

ELECTRICAL NOTES

LEGEND
ACR-LINE ACROSS THE LINE START
CB CIRCUIT BREAKER
DE FU DUAL ELEMENT FUSE
DISC SW DISCONNECT SWITCH
FACT MOUNT CB FACTORY-MOUNTED CIRCUIT BREAKER
FACT MOUNT FUSE FACTORY-MOUNTED FUSES
FLA FULL LOAD AMPS
HZ HERTZ
MAX MAXIMUM
MCA MINIMUM CIRCUIT AMPACITY
MIN MINIMUM
MIN NF MINIMUM NON-FUSED
RLA RUNNING LOAD AMPS
S.P. WIRE SINGLE-POINT WIRING
UNIT-MOUNTED SERVICE (NON-FUSED DISCONNECT SWITCH)
WYE-DELTA WYE-DELTA START
XLRA ACROSS-THE-LINE INRUSH LOCKED ROTOR AMPS
YLRA WYE-DELTA INRUSH LOCKED ROTOR AMPS
FORM 201.18-NM4
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