52
7. WIRING [Connecting the Power Cable]
●
Install an earth leakage circuit breaker at the right primary side of the air compressor.
Do not install a disconnect switch such as a knife switch in the wiring, as it is not protect the air
compressor and may result in the burning of motors if a ground fault occurs.
●
Ground the air compressor to prevent electric shock or an air compressor failure. Ground
independently and directly to the earth (Do not use the steel skeleton of the building as a ground, as it
could cause an operational failure).
CAUTION
Remove the control panel cover and connect the power
cables as illustrated below.
Protect the power cables with using attached
rubber bush, conduits and/or protective tubes.
An unprotected power cable can come into
direct contact with the steel plates on the
power cable holes with a slight amount of
vibration. This could damage the cover over
time and result in a short circuit accident.
CAUTION
Do not use simple disconnect such as knife switch in
wiring.
The type and sizing not supplied by Hitachi is the
responsiblitiy of the customer.
NOTE: Use the earth leakage circuit breaker that is
sensitivity-current-switchable (selectable,either
100 mA or 200 mA) and set its earth leakage
sensitivity current to 200 mA
⑤
Disconnect the power and verify that it is safe before
1.) Overhauling the DSP, 2.) Adding oil to the DSP
and/or 3.) Servicing the starter/control box.
⑥
Field wiring connections must be made by UL and
CSA certificated ring lug terminal connectors sized
for the wire gauge being used. The connector must
be fixed using the crimping tool specified by the
connector manufacturer.
7.3 Connecting the Power Cable
①
Wiring inside the air compressor is completed prior
to shipment by Hitachi.
Refer to
“
Wiring Diagram
”
on
7. 4
.
②
Ground resistance requirements are required when
connected the power cable and grounding cable.
The ground resistance requirements are shown in
the table below:
Power Supply Voltage Ground Resistance Type Ground Resistance Value
460V
Type C
10
Ω
or less
③
For ser vice accessibility to the air compressor,
install the power cable away from the enclosure.
④
Both main disconnect means and branch circuit
protection shall be provided. In addition, main
disconnect means shall be provided on the line side
of the branch circuit protection.
The type(Fuse disconnect, Circuit breaker, or Earth
leakage (ground) circuit breaker) and its sizing
must be selected in accordance with national or local
electric code requirements. (Recommendation type:
(
“
Wiring Diagram
”
)