Electrical Notes - York MILLENNIUM YCAS 250 Manual

Air cooled liquid chiller

Table of Contents

Technical Data

NOTES & LEGEND

(for pages 50 - 53)

1. Minimum circuit ampacity (MCA) is based on 125% 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 430-24. If a Factory Mounted Control Transformer is provided, add the following to

the system #1 MCA values in the YCAS Tables: -17, add 15 amps; -28, add 12 amps; -40, add 7 amps; -46, add 6 amps; -58, add 5 amps.

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 connectors 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 start, must also include

factory provided circuit breakers in each motor control center. All 3 & 4 compressor machines equipped with Star-Delta compressor

motor start 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. High Static Fans are 3.8 kW each.

12. FLA for "Low Noise Fan" motors: 200V = 8.0A, 230V = 7.8A, 380V = 4.4A, 460V = 3.6A, 575V = 2.9A.

13. Group Rated breaker must be HACR type for cU.L. Machines.

LEGEND

ACR-LINE

ACROSS THE LINE START

C.B.

CIRCUIT BREAKER

D.E.

DUAL ELEMENT FUSE

DISC SW

DISCONNECT SWITCH

FACT CB

FACTORY-MOUNTED CIRCUIT BREAKER

FLA

FULL LOAD AMPS

HERTZ

MAX

MAXIMUM

MCA

MINIMUM CIRCUIT AMPACITY

MIN

MINIMUM

MIN NF

MINIMUM NON-FUSED

RLA

RUNNING LOAD AMPS

S.P. WIRE

SINGLE-POINT WIRING

Y-∆

WYE-DELTA START

X-LRA

ACROSS-THE-LINE INRUSH LOCKED ROTOR AMPS

Y-LRA

WYE-DELTA INRUSH LOCKED ROTOR AMPS

CONTROL POWER SUPPLY (UNITS WITHOUT STANDARD CONTROL CIRCUIT TRANSFORMER)

NO. OF

COMPRESSORS

3 or 4

(Non-CE 50/60Hz)

(CE 50Hz)