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7. WIRING
7.1 Power Supply Equipment
Use a power supply transformer with adequate kVA
capacity and a power cable with adequate thickness and
length. If properly sized transformers and cables are not
used, excessive voltage drop could occur when the
START
button is pressed, resulting in 1.) Motors failing
to fully accelerate and/or, 2.) An inefficiently energized
control circuit; thus shutting down the air compressor.
To keep a starting voltage drop within an allowable range
(5% of the rated voltage), use the power supply
7.2 MIV and WIVM wiring
Model
DSP-90A6N
DSP-90W6N
DSP-110A6N
DSP-110W6N
DSP-90VA6N
DSP-90VW6N
DSP-110VA6N
DSP-110VW6N
Power Supply Voltage
460V
Power Transformer Capacity
(1)
(KVA)
200 or more
250 or more
200 or more
250 or more
Power Cable Thickness AWG (mm
2
)
4/0 to 300
(125 to 150)
250 to 300
(125 to 150)
4/0 to 300
(125 (2) to 150)
250 to 300
(125 to 150)
Capacity values are reference data; some power supplies may require a larger-capacity transformer.
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 control panel to service or wire the air compressor, disconnect the power; otherwise
you may receive an 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.
transformer and power cable shown below table. Lower
thickness values are based on the power cable length of
less than
393 inches (10 m)
. In the event that the power
cable is longer than
393 inches (10 m)
, employ a thicker
power cable. Provide intermediate terminals to keep the
power cable thickness lower than the maximum values at
the air compressor terminal block. The maximum
voltage imbalance between the phases shall be within 1%.
WARNING
①
Electrical wiring of Motorized Isolation Valve (MIV),
and Motarized Water Isolation Valve (WIVM) shall
be install on side. Refer to the drawing.
(WIVM is only for water-cooled.)
1
2
3
4
5
WIRING No. '44'
WIRING No. 'DA'
WIRING No. '43'
WIRING No. 'DA'
WIRING No. '46'
WIRING No. '45'
CABLE FROM TB3 IN THE CONTROL PANEL
CABLE FROM TB3 IN THE CONTROL PANEL
WIRING FOR MIV
WIRING FOR WIVM
TERMINAL BOX OF MIV
TERMINAL BOX OF WIVM
BLACK
WHITE
RED
GREEN
YELLOW
