Unit; General Information; General Verifications; Electrical Wiring Connection Ch Units - Hitachi FSXN Series Service Manual

4 Electrical wiring
4.2 CH unit

4.2.1 General information

D A N G E R
• Turn OFF the main power switch to the CH unit, the indoor unit and the outdoor unit before electrical wiring
work or a periodical check is performed.
• Protect the wires, electrical parts, etc. from rats or other vermin.
• Use a medium sensing speed type ELB (Electric Leakage Breaker, activation speed of 0.1 sec. or less). If not
used, it will cause an electric shock or a fire.
Fix the cables securely. External forces on the terminals could lead to a fire.
C A U T I O N
• Wrap the accessory packing around the wires, and plug the wiring connection hole with the seal material to
protect the product from any condensate water or insects.
• Tightly secure the wires with the cord clamp inside the electrical box.
• Use twisted shielded pair cable or shield pair cable for transmission wires between the indoor and the outdoor
units (Max. 1000 m), and connect the shielded part to the earth screw in the electrical box of the indoor unit as
shown the next page figure.

4.2.2 General verifications

1 Make sure that the field-selected electrical components (main power switches, circuit breakers, wires, conduit
connectors and wire terminals) have been properly selected according to the electrical data indicated in Technical
Catalogue. Make sure that the components comply with National Electrical code (NEC).
2 Check to ensure that the power supply voltage is within ±10% of rated voltage.
3 Check the power source capacity is too low, the system cannot be started due to the voltage drop.
4 Check to ensure that the ground wire is connected.

4.2.3 Electrical wiring connection CH units

The electrical wiring connection for the CH unit is shown in next figure.
1 Turn OFF the main power switch and take off the electrical box cover of CH unit.
2 Connect the power supply and earth wires to the terminals in the electrical box.
3 Connect the wires of the operating line to the terminals in the electrical box.
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SMGB0065 rev. 1 - 12/2010
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