Hitachi RUA-NP10ATS, Instruction Manual

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4
ELECTRICAL WIRING
3. ELECTRICAL WIRING
Tools and Instruments – One set of wiring tools,
electrical tester (Clamp meter).
Schedule Check – Confirm that the field selected
electrical components (main power switch, fuses,
wires, conduit connections, wire terminals) are
properly selected according to "Electrical Data" in
Technical Catalog
, and ensure that they comply
Ⅰ
with national and local codes. It is recommended
that the main power switch be locked at the OFF
position, to prevent against accidental supply of
the power during unit servicing.
Service Panel – Access to the magnetic switch
box is provided from the service panel, which is
fixed with screws (see the panel location in the
Operation Instructions.)
3.1 Main Power Wiring Procedures
Confirm that electrical power is not being
supplied to the installation location prior to any
electrical installation work.
1. Install the field-supplied main switch box at the
properly selected location.
2. Install conduit connectors in the hole for power
wiring (knockout holes).
3. Lead the main power wires and the earthing
wire through the connector to the screw
terminals for main power and earthing in the
magnetic switch box. The neutral wire to 380V
and 415V power supplies should also be led
through the connector. Firmly connect the
wires with wire terminals to the unit screw
terminals R(L1),S(L2) and T(L3) and also
Mp(N) for 380V and 415V power supplies
according to Fig. 6 or the wiring label attached
to the magnetic switch box.
A scroll compressor is equipped. Because that
the rotation direction of the orbiting scroll of the
HITACHI scroll type compressor is fixed,
therefore a reverse & single phase sequence
protection relay is equipped in this unit. If each
phase R, S or T of the power source is
incorrectly connected, the compressor does not
start due to the activation of the reverse & single
phase sequence protection relay. Therefore, in
order to check the correct wiring connection, the
utilization of a phase sequence indicator is
recommended when the unit is started after
installation of the unit.
(1) If the phase is wrong, exchange two of the
three wires connected from the main power
source to the main terminals of the unit as
indicated with dotted lines, and then check the
rotation direction of the phase sequence
indicator once again. Do not exchange the
wires in the unit in order to protect the
compressor against the reversal rotation.
(2) Do not operate the compressor by depressing
the button of the magnetic switch for the
compressor.
A three-phase condenser fan motor is equipped;
therefore, the fan motor rotation should be
checked. Interchange two of the three main
power source wires, if incorrect rotation is
detected during initial start-up.
3.2 Control Wiring
Install the optional room thermostat at a suitable
location in the space to be air-conditioned.
Connect the control wires between the unit
terminals and the thermostat terminals according
to Fig. 6 or the wiring label. If a locally-supplied
thermostat and switch are installed, connect the
wiring according Technical Catalog
Ⅰ
.
Fig. 6. Field Wiring Connection
RUA-NP4ATS through RUA-NP8ATS Connectors A D F
RUA-NP9ATS and RUA-NP10ATS Connectors A D E F