Power Supply Wiring
56 CVHH-SVX001A-EN
Option 1—PFCCs installed downstream of
starter contactor, upstream of current
transformers.
Note: Graphic labels (shown above) are used for CE
application only.
Important:
• Before servicing, disconnect all power sources and
allow at least 30 minutes for capacitors to discharge.
• All electrical enclosures—unit or remote—are IP2X.
Simultaneously disconnect capacitors and load from line
power. If the capacitors are not switched offline when the
load is disconnected, they continue to add capacitance to
the electrical distribution system. A leading power
factor—too much capacitance—may eventually develop.
This overprotection causes poor voltage regulation (i.e.,
voltage is high when the circuit is unloaded, then drops as
loads are added).
Option 2—PFCC wires routed through current
transformers.
Size motor overload protection to account for capacitor-
supplied current. Overloads are typically set to measure
the total current drawn by the motor. When PFCCs are
used, they become the source of part of that current. If the
current they provide is not registered by the overload
protectors, potentially damaging amperage can reach the
motor. The simplest way to ensure that the overloads
detect all current supplied to the motor is to position the
PFCCs upstream of the current transformers as shown in
the preceding figure. If the capacitor connection points are
downstream of the current transformers, route the PFCC
leads through the current transformers as shown in the
following figure. This ensures that the overloads register
both line and capacitor-supplied current.
Interconnecting Wiring
Typical equipment room conduit layouts with and without
unit-mounted starters are shown in
Figure 30 and
Figure 31.
Important: The interconnecting wiring between the
starter panel, compressor, and control
panel is factory-installed w ith unit-mounted
starters. However, when a remote-mounted
starter is used, the interconnecting wiring
must be field-installed.
Note: Refer to starter submittal drawing for location of
incoming wiring to the starter.
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 an appropriate voltmeter that all
capacitors have discharged.
For additional information regarding the safe discharge of
capacitors, see PROD-SVB06* -EN
Motor
Fuses
Enclosed
3-phase
capacitor
unit
Fused
disconnect
or suitable
breaker
Power
circuit
1
2
3
Current
transformer
Motor starter
contactor
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