Carrier AquaEdge 19XR Start-Up, Operation And Maintenance Instructions Manual page 83

I. GENERAL
1.0 Variable Frequency Drive (VFD) shall be designed and manu-
factured in accordance with Carrier Engineering Requirement
Z-416.
1.1 All field-supplied conductors, devices, and the field installation
wiring, termination of conductors and devices, must be in com-
pliance with all applicable codes and job specifications.
CAUTION
To prevent damage to machine, do NOT punch holes or drill into
the top surface of the VFD enclosure for field wiring. Field wiring
knockouts are provided on the top and side of the VFD enclosure
for field wiring connections.
1.2 The routing of field-installed conduit and conductors and the
location of field-installed devices must not interfere with equip-
ment access or the reading, adjusting, or servicing of any com-
ponent.
1.3 Equipment installation and all starting and control devices must
comply with details in equipment submittal drawings and litera-
ture.
1.4 Contacts and switches are shown in the position they would
assume with the circuit de-energized and chiller shutdown.
1.5 WARNING - Do not use aluminum conductors.
1.6 Installer is responsible for any damage caused by improper wir-
ing between VFD and machine.
1.7 All field-installed wiring is field-supplied.
II. POWER WIRING TO VFD
2.0 Provide a means of disconnecting power to VFD.
2.1 Lug adapters may be required if installation conditions dictate
that conductors be sized beyond the minimum ampacity
required. Contact VFD supplier for lug information.
2.2 Compressor motor and controls must be grounded by using
equipment grounding lug provided inside VFD enclosure.
III. CONTROL WIRING
3.0 Field supplied control conductors to be at least 18 AWG or
larger.
3.1 Optional ice build start/terminate device contacts, optional
remote start/stop device contacts, and optional spare safety
device contacts (devices not supplied by Carrier), must have 24
VAC rating. MAX current is 60 mA, nominal current is 10 mA.
Switches with gold-plated bifurcated contacts are recom-
mended.
3.2 Each integrated contact output can control loads (VA) for evap-
orator pump, condenser pump, tower fan low, tower fan high,
and alarm annunciator devices rated 5 amps at 115 VAC and
up to 3 amps at 277 VAC.
CAUTION
Control wiring for Carrier to start pumps and tower fan motors
and establish flows must be provided to assure machine protection.
If primary pump, tower fan, and flow control is by other means, also
provide parallel means for control by Carrier. Failure to do so could
result in machine freeze-up or overpressure.
Do not use control transformers in the control center as the
power source for external or field-supplied contactor coils,
actuator motors, or any other loads.
3.3 Do not route control wiring carrying 30 v or less within a con-
duit which has wires carrying 50 v or higher or along side wires
carrying 50 v or higher.
3.4 Control wiring between VFD and power panel must be sepa-
rate shielded cables with minimum rating 600 v, 80 C. Ground
shield at VFD.
3.5 If optional pumpout/oil pump circuit breaker is not supplied
within the starter enclosure, it must be located within sight of
machine with wiring routed to suit.
3.6 When providing conductors for oil pump motor and oil heater
power, refer to sizing data on label located on the chiller power
panel, equipment submittal documentation, or equipment prod-
uct data catalog.
3.7 Spare 4-20 mA output signal is designed for controllers with a
non-grounded 4-20 mA input signal and a maximum input
impedance of 500 ohms.
IV. POWER WIRING BETWEEN FREE-STANDING VFD AND COM-
PRESSOR MOTOR
4.0 Medium voltage (over 600 volts) compressor motors have (3)
terminals. Motor terminal connections below 2.1 kV are
threaded and above 2.1 kV they are
compression lug with a single hole can be connected directly to
the stud or 3 adapters are supplied for connecting a NEMA lug
for two 1 / -in. stud connections per phase. Use suitable connec-
2
tors and insulation for high voltage alternating current cable ter-
minations (these items are not supplied by Carrier). Compressor
motor starter must have nameplate stamped as to conforming
with Carrier Engineering requirement " Z-416."
4.1 Power conductor rating must meet minimum unit nameplate
voltage and compressor motor RLA. Refer to the label located
on the side of the chiller control panel, equipment submittal
documentation, or equipment product data catalog for conduc-
tor sizing data. (Conductor as defined below may be a single
lead or multiple smaller ampacity leads in parallel for the pur-
pose of carrying the equivalent or higher current of a single
larger lead.)
When (3) conductors are used:
Minimum ampacity per conductor = 1.25 x compressor RLA
When 96) conductors are used:
Minimum ampacity per conductor = 1.25 x compressor RLA/2
4.2 When more than one conduit is used to run conductors from
VFD to compressor motor terminal box, an equal number of
leads from each phase (conductor) must be in each conduit to
prevent excessive heating (for example, conductors to motor
terminals 1, 2, and 3 in one conduit, and to 1, 2, and 3 in
another conduit).
4.3 Compressor motor power conductors may enter terminal box
through top, left side, or bottom left using holes cut by contrac-
tor to suit conduit. Flexible conduit should be used for the last
few feet to the terminal box for unit vibration isolation. Use of
stress cones may require an oversize (special) motor terminal
box (not supplied by Carrier).
4.4 Compressor motor frame to be grounded in accordance with
the National Electrical Code (NFPA-70) and applicable codes.
Means for grounding compressor motor is a #4 AWG to 500
MCM pressure connector, supplied and located in the lower left
corner of the compressor motor terminal box.
4.5 Do not allow motor terminals to support weight of wire cables.
Use cable supports and strain reliefs as required.
4.6 Use backup wrench when tightening lead connectors to motor
terminal studs. Torque to 30-35 ft-lb for the
40 ft-lb for the ¾-in. stud.
4.7 Do not exceed 100 ft. maximum power cable length between
the VFD and motor terminals without consulting Carrier for
special requirements.
CABLE INSULATION REQUIREMENTS
SYSTEM
VOLTAGE
2400
3000
3300
4160
6000
6300
6600
83
9 / -in. threaded stud. A
16
9 / -in. stud and 35-
16
CABLE INSULATION RATING (kV)
(MAX. PEAK LINE-TO-GROUND)
LINE SIDE MACHINE SIDE
> 2.20 > 2.20
> 2.75 > 2.75
> 3.00 > 3.00
> 3.80 > 3.80
> 5.50 > 5.50
> 5.80 > 5.80
> 6.00 > 6.00
3 / -in.
4