Wiring; Miv And Wivm Wiring; Connecting A Power Cable - Hitachi NEXT Series Instruction Manual

7. WIRING

1. Always use a licensed electrician. Do not allow an unlicensed person to wire the air compressor. An
unlicensed person may wire the air compressor wrongly, and a wrong wiring may cause an electric shock.
2. Do not remove any protective relays on the air compressor. Also, do not make a modification of the
control circuit that may result in impairing the protective relay's function. Remember that the loss of the
protective relay's function may cause serious damage to the air compressor such as a burning of the air
end. In the event that you need to modify the control circuit, consult your distributor.
3. Before opening the starter/control box cover to service or wire the air compressor, disconnect the power;
otherwise you may receivean electric shock. In addition, attach a notice on the power supply stating "Under
the maintenance work. Keep the switch off." to prevent someone from carelessly turning the switch on.
7.1 Power Source Transformer and Power Cable
Prepare a power supply transformer with adequate
capacity. Also, use a power cable with adequate thickness
and length. Otherwise, an excessive voltage drop may
occur when you have pressed the START button; accord-
ingly the DSP motor may fail to fully accelerate.
Also a control circuit may occur be energized insuffi-
ciently ; accordingly the DSP may be shut down.
Model
Power Supply Voltage
Power Transformer
Capacity (1) (KVA)
Power Cable Thickness
mm2 (AVG)
NOTES:
(1) Capacity values are reference data; some power supplies may require a larger-capacity transformer.
(2) Lower thickness values are based on the power cable length of less than 20 m. In the event that the power cable is longer than 20m,
employ a thicker one. Provide intermediate terminals to keep the thickness lower than the maximum values at the air compressor terminal
block.

7.2 MIV and WIVM wiring

① Electrical wiring of Motorized Isolation Valve (MIV),
which is attached at left side panel, and Motarized
Water Isolation Valve (WIVM) shall be done on side.
Refer to below drawing.
WIRING FOR MIV
WIRING No. 'DA'
1
WIRING No. '44'
2
3
WIRING No. '43'
4
CABLE FROM TB3 IN THE CONTROL PANEL
5
TERMINAL BOX OF MIV
WIRING FOR WMIV
WIRING No. 'DA'
BLACK
WIRING No. '46'
WHITE
WIRING No. '45'
RED
GREEN
CABLE FROM TB3 IN THE CONTROL PANEL
YELLOW
TERMINAL BOX OF WIVM
WARNING
DSP-132W6N DSP-145W6N
350 or more
150(2) to 250
(250 to 350)
Always control the maximum drop of starting voltage
within 5% of the rated voltage. To do so, use the power
supply transformer and power cable as listed in the table
below.
The maximum voltage imbalance between the press shall
be within 1%.
DSP-160(V)W6N DSP-200W6N
400V Class
200(2) to 250 250(2) or more
(300 to 350) (4/0×2 or more)

7.3 Connecting a Power Cable

① Wiring inside the DSP is completed prioer to ship-
ment by Hitachi.
Refer to "Wiring Connection Diagram" (
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
③ Connect the power cable so that ease of disassem-
bling and reassembling the enclosure panels is taken
into consideration.
④ The compressor requires its own branch circuit pro-
tection adjacent to the compressor.
The type (Fuse disconnect, Circuit breaker, or Earth
leakage (ground) circuit breaker) and its sizing must
be selected in accordance with national or local elec-
tric code requirements . (Recommendation type:
4. Wiring Connection Diagram) Do not use simple
disconnect such as a knife switch in wiring.
The type and sizing not supplied by Hitachi is the
responsibility of the customer.
NOTE: If the earth leakage circuit breaker is used, the sen-
sitivity-current is set to 200 mA.
DSP-240(V)W6N
500 or more
325(2) or more
(250×2 or more)
47-48).
Type C 10Ω or less
47