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Electrical System Installation
Due to our policy of continuous product innovation, some specifications may change without notification.
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ELECTRICAL SYSTEM
WARNING
• Ground wiring is required to prevent accidental electrical shock during current leakage, communication problems from electrical noise, and
motor current leakage.
Do not connect the ground line to the pipes. There is risk of fire, electric shock, explosion, physical injury or
death.
• Install a main shutoff switch that interrupts all power sources simultaneously. There is risk of fire, electric shock explosion, physical injury or
death.
• Communication cable between Main outdoor unit to Sub outdoor unit(s), and Main outdoor unit to DOAS to be 18 AWG, 2-conductor,
twisted, stranded, shielded. Ensure the communication cable shield is properly grounded to the Main outdoor unit chassis only.
Do not
ground the outdoor unit to DOAS communication cable at any other point. Wiring must comply with all applicable local and national codes.
Inadequate connections may generate heat, cause a fire, and physical injury or death.
• The GND terminal at the main PCB is a negative terminal for dry contact, not a ground. Inadequate connections may generate heat, cause a
fire, and physical injury or death.
• Make sure that the terminal numbers of Main outdoor unit and Sub outdoor unit(s) match (A to A, B to B). The system will malfunction if not
properly wired.
• Maintain polarity throughout the communication network. The system will malfunction if not properly wired.
• If the system operates in reversed phase, it may break the compressors and other components.
• 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. Operating the system in reverse phase may break the compressor and other unit com-
ponents.
Outdoor Unit to DOAS Wiring / Cable System