Electrical Notes - Quantech QWC3 Manual

FORM QWC3-EG1 (217)

Electrical Notes

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 43024. If the optional Factory Mounted Control
Transformer is provided, add the following MCA values to the electrical tables for the system providing power to the trans-
former: 17, add 2.5 amps; 28, add 2.3 amps; 40, add 1.5 amps, 46, add 1.3 amps; 58, add 1 amps.
2. MCA for units with optional external compressor overloads is calculated at 54/44 evaporator (water), 85/95 condenser
(water) condition per UL1995. If unit is to be operated at higher temperatures, increase Service Wiring and Equipment
accordingly.
3. For Leaving Condenser Temperatures above 95°F (with maximum limit of 110°F) use the following formula:
4. 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. Article 440.
5. Minimum fuse size is based upon 150% of the rated load amps for the largest motor plus 100% of the rated load amps
for all other loads included in the circuit to avoid nuisance trips at startup due to lock rotor amps. It is not recommended
in applications where brown outs, frequent starting and stopping of the unit, and/or operation at ambient temperatures in
excess of 95ºF (35ºC) is anticipated.
6. Maximum fuse size 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.
7. Circuit breakers must be UL listed and CSA certified and maximum size is based on 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. Otherwise, an HACR type circuit
breakers must be used. Maximum HACR circuit breaker rating is based on 225% of the rated The "INCOMING WIRE
RANGE" is the minimum and maximum wire size that can be accommodated by the unit wiring lugs. The (2) preceding
the wire range indicates the number of termination points available per phase of the wire range specified. Actual wire size
and number of wires per phase must be determined based on the National Electrical Code, using copper connectors only.
Field wiring must also comply with local codes.
8. An equipment ground lug(s) is provided for the incoming power. Ground line sizing shall be in accordance with the current
NEC Table 250-122.
9. The supplied disconnect is a "Disconnecting Means" as defined in the N.E.C. 100, and is intended for isolating the unit
for the available power supply to perform maintenance and troubleshooting. This disconnect is not intended to be a Load
Break Device.
10. Field Wiring by others which complies to the National Electrical Code & Local Codes.
11. Voltage Utilization Range
LEGEND
ACR ACROSS THE LINE START
C.B. CIRCUIT BREAKER
D.E. DUAL ELEMENT FUSE
DISC SW DISCONNECT SWITCH
FACT MOUNT CB FACTORY MOUNTED CIRCUIT BREAKER
FLA FULL LOAD AMPS
HZ HERTZ
MAX MAXIMUM
MCA MINIMUM CIRCUIT AMPACITY
MIN MINIMUM
MIN NF MINIMUM NON FUSED
RLA RATED LOAD AMPS
S.P. WIRE SINGLE POINT WIRING
UNIT MTD SERV SW UNIT MOUNTED SERVICE (NON-FUSED DISCONNECT SWITCH)
LRA LOCKED ROTOR AMPS
ECWT ENTERING CONDENSER WATER TEMPERATURE
54
RMCA = MCA * (1 + (DLCT - 95)/100 )
DLCT is "Design Leaving Condenser Temperature"
RMCA is "Recommended Minimum Circuit Ampacity"
Rated Voltage Utilization Range
208/60/3 187 - 229
230/60/3 200 - 254
380/60/3 342 - 402
460/60/3 414 - 508
575/60/3 520 - 635
QUANTECH