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NOTES (pages 50 - 54)
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 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 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 Electric 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-Delta Compressor motor starters, must also
include factory-provided circuit breakers in each motor control center. 3 & 4-compressor machine equipped with Star-Delta compressor
motor starter, must also include factory-provided 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.
FACT MOUNT FUSE
UNIT MTD SERV SW
YORK INTERNATIONAL
ELECTRICAL DATA
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
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-NM8
7
55
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