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Wiring
Torquing Electrical Power Connections
WARNING
Hazardous Voltage w/Capacitors!
Failure to disconnect power and discharge capacitors
before servicing could result in death or serious injury.
Disconnect all electric power, including remote
disconnects and discharge all motor start/run
capacitors before servicing. Follow proper lockout/
tagout procedures to ensure the power cannot be
inadvertently energized. For variable frequency drives
or other energy storing components provided by Trane
or others, refer to the appropriate manufacturer's
literature for allowable waiting periods for discharge of
capacitors. Verify with a CAT III or IV voltmeter rated
per NFPA 70E that all capacitors have discharged.
Use a torque wrench to tighten power connections. A torque
wrench eliminates the human element and provides proper
hardware tightening.
Proper torque for connections depends on both the bolting
materials and the metals being connected. Strand migration
will occur when the copper is under prolonged pressure.
Electrical power terminations should be rechecked for
tightness when the apparatus is first installed and periodically
afterwards. The conductor could flow under prolonged
pressure. Thermal cycling will be greater during the first few
months in operation.
Most hardware used for making a bolted electrical joint will be
low carbon steel. The hardware does not carry electrical
current but holds the two conducting surfaces together under
pressure. When properly torqued, the slight elongation of the
bolt or screw acts to maintain pressure on the electrical joint.
The thermal expansion of steel is less than that of the
conducting metals, which is usually copper.
The pressure at the electrical joint will vary slightly during
thermal cycling and reduces somewhat when there is cold flow
in the conducting metals. Re-torquing will re-establish the
surface pressure, which is essential to keeping a low
resistance drop between the two conducting surfaces and
avoiding eventual failure.
Cabinet Wire Routing
All wiring should be installed in conformance with the
applicable local, national, and international codes (for
example, NEC/CEC). Control wiring enters the cabinet
through the left side and terminates at the control panel's
terminal block. Tighten the control wire connections to 7.1 to
8.9 in·lb (0.8 to 1.0 N·m).
42
Wire Routing
WARNING
Proper Field Wiring and Grounding
Required!
Failure to follow code could result in death or serious
injury. All field wiring MUST be performed by qualified
personnel. Improperly installed and grounded field
wiring poses FIRE and ELECTROCUTION hazards. To
avoid these hazards, you MUST follow requirements for
field wiring installation and grounding as described in
NEC and your local/state/national electrical codes.
Wire Sizing
Care should be taken to see that all interconnection wiring and
ground wiring is sized and installed in conformance with the
National Electrical Code (NEC), the National Fire Protection
Association (NFPA), or the Canadian Electrical Code (CEC) as
applicable, and other appropriate local codes. Refer to
controller and motor nameplates for electrical data.
Important:
•
Before servicing, disconnect all power sources and allow
at least 20 minutes for capacitors to discharge.
•
All electrical enclosures-unit or remote-are IP2X.
Grounding the Cabinet
Refer to submittals for power lug sizes and location along with
control wiring specifics for the controller.
Use the following steps to ground the cabinet:
1. Open the left-hand enclosure door of the drive. The
grounding stud is located just above and to the left of the
breaker.
2. Run a suitable earth ground completed by field) to the
cabinet's ground connection point. The grounding lug is
capable of accepting up to 4/0 AWG wire. For AWG/MCM
2
equivalents in mm
, refer to
ground connections to 375 in·lb (42.4 N·m).
NOTICE
Equipment Damage!
Failure to follow instructions below could cause
interference with drive operation and result in damage
to the equipment.
Route signal and control wiring separately and in
different conduit from power wiring.
Table 4, p.
41. Tighten the
VFDB-SVX001C-EN
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