Electrical Connections; Power-Supply/Power-Wiring Specifications - Emerson Liebert SRC18 User Manual

6.0 Electrical Connections

WARNING
!
Arc flash and electric shock hazard. Can cause serious injury or death. Open all local and remote
electric power disconnect switches, verify with a voltmeter that power is off and wear personal
protective equipment per NFPA 70E before working within the electric control enclosure.
WARNING
!
Risk of electric shock and overheated wiring. Can cause injury or death. All field-supplied power
wiring, overcurrent protection (circuit breakers/fuses) and earth grounding must be installed by a
trained and qualified HVAC technician in accordance with local, state, and National Electrical Code
regulations related to electrical equipment and wiring.
• Read and follow explicitly all instructions and safety alert messages in this manual.
• Do not connect ground wire to refrigerant, gas or water piping, to lightning rods, to telephone
ground wiring, or to the building plumbing system.
• Replace and securely fasten all control box and panel covers immediately after working on the
unit to protect the operator from the hazards above.
NOTICE
Risk of electrical phase reversal. Can cause equipment damage, unit malfunction and loss of
cooling operation.
If there is a possibility of reversed phase, phase loss, momentary blackout, or the power goes on
and off while the system is operating, install a field-supplied phase-loss protection circuit.
NOTE
Consider ambient conditions (temperature, direct sunlight, inclement weather,
etc.) when selecting, installing, and connecting the power wiring.

6.1 Power-supply/Power-wiring Specifications

• Liebert SRC systems operate at 1∅, 208 – 230 V, 60 Hz.
• Power-supply wire type and size should be selected based on National Electrical Code and local
codes. Maximum allowable voltage fluctuation ±10% or nameplate rated value. Refer to Figure 6-1 for
wiring guidelines.
• Properly ground the indoor and outdoor unit per National Electrical Code and local codes.
• Use only copper wiring that is stranded and shielded with the wires separately insulated.
• Ground wire should be longer than the common power/communication wires.
• Refer to the appropriate circuit and terminal-block diagrams for your model unit.
• Always match color codes of each wire and follow wiring diagram.
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Electrical Connections
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Liebert SRC™ User Manual