Cables And Wiring Length - Mitsubishi Electric F700 Instruction Manual

1.3.3

Cables and wiring length

(1) Applied cable size
Select the recommended cable size to ensure that a voltage drop will be 2% max.
If the wiring distance is long between the inverter and motor, a main circuit cable voltage drop will cause the motor
torque to decrease especially at the output of a low frequency.
The following table indicates a selection example for the wiring length of 20m.
400V class (when input power supply is 440V based on the rated current for 110% overload for 1 minute)
Terminal
Applicable
Screw
Inverter Type
Size
*4
FR-F740-00023 to
M4
00083-EC
FR-F740-00126-EC M4
FR-F740-00170-EC M4
FR-F740-00250-EC M4
FR-F740-00310-EC M5
FR-F740-00380-EC M5
FR-F740-00470-EC M6
FR-F740-00620-EC M6
FR-F740-00770-EC M6
FR-F740-00930-EC M8
FR-F740-01160-EC M8
FR-F740-01800-EC M8
FR-F740-02160-EC M10
*1 For the 01160 or less, the recommended cable size is that of the HIV cable (600V class 2 vinyl-insulated cable) with continuous maximum permissible
temperature of 75°C. Assumes that the ambient temperature is 50°C or less and the wiring distance is 20m or less.
For the 01800 or more, the recommended cable size is that of LMFC (heat resistant flexible cross-linked polyethylene insulated cable) with continuous
maximum permissible temperature of 105°C. Assumes that the ambient temperature is 50°C or less and wiring is performed in an enclosure.
*2 For the 00930 or less, the recommended cable size is that of the THHW cable with continuous maximum permissible temperature of 75°C. Assumes that
the ambient temperature is 40°C or less and the wiring distance is 20m or less.
For the 01160 or more, the recommended cable size is that of THHN cable with continuous maximum permissible temperature of 90°C. Assumes that
the ambient temperature is 40°C or less and wiring is performed in an enclosure.
*3 For the 00930 or less, the recommended cable size is that of the PVC cable with continuous maximum permissible temperature of 70°C. Assumes that
the ambient temperature is 40°C or less and the wiring distance is 20m or less.
For the 01160 or more, the recommended cable size is that of XLPE cable with continuous maximum permissible temperature of 90°C. Assumes that the
ambient temperature is 40°C or less and wiring is performed in an enclosure.
*4 The terminal screw size indicates the terminal size for R/L1, S/L2, T/L3, U, V, W, and a screw for earthing.
The line voltage drop can be calculated by the following expression:
3 × wire resistance[mΩ/m] × wiring distance[m] × current[A]
line voltage drop [V]=
Use a larger diameter cable when the wiring distance is long or when it is desired to decrease the voltage drop
(torque reduction) in the low speed range.
CAUTION
· Tighten the terminal screw to the specified torque.
A screw that has been tighten too loosely can cause a short circuit or malfunction.
A screw that has been tighten too tightly can cause a short circuit or malfunction due to the unit breakage.
· Use crimping terminals with insulation sleeve to wire the power supply and motor.
(2) Notes on earthing
Leakage currents flow in the inverter. To prevent an electric shock, the inverter and motor must be earthed. ((This
inverter must be earthed. Earthing must conform to the requirements of national and local safety regulations and electrical
codes. (JIS, NEC section 250, IEC 536 class 1 and other applicable standards)
Use the dedicated earth terminal to earth the inverter. (Do not use the screw in the casing, chassis, etc.)
Use the thickest possible earth cable.Use the cable whose size is equal to or greater than that indicated in the
above table, and minimize the cable length. The earthing point should be as near as possible to the inverter.
Crimping
Tightening
Terminal
Torque
R/L1, S/L2, R/L1, S/L2,
N·m
U, V, W
T/L3
1.5 2-4 2-4
1.5 2-4 2-4
1.5 5.5-4 5.5-4
1.5 5.5-4 5.5-4
2.5 8-5 8-5
2.5 14-5 8-5
4.4 22-6 14-6
4.4 22-6 22-6
4.4 22-6 22-6
7.8 38-8 38-8
7.8 60-8 60-8
7.8 60-10 60-10
14.7 100-10 100-10
1000
Main circuit terminal specifications
Cable Sizes
2
HIV, etc. (mm )
*1
Earth
R/L1, S/L2,
U, V, W Cable
T/L3 T/L3
Gauge
2 2 2 14
2 2 3.5 12
3.5 3.5 3.5 12
5.5 5.5 8 10
8 8 8 8
14 8 14 6
22 14 14 4
22 22 14 4
22 22 14 4
38 38 22 1
60 60 22 1/0
60 60 38 1/0
100 100 38 3/0
AWG
PVC, etc. (mm
*2
R/L1, S/L2,
U, V, W U, V, W
T/L3
14 2.5 2.5
14 2.5 2.5
12 4 4
10 6 6
8 10 10
8 16 10
6 25 16
4 25 25
4 25 25
2 50 50
1/0 50 50
1/0 50 50
3/0 70 70
2
)
*3
Earth
Cable
Gauge
2.5
4
4
10
10
16
16
16
16
25
25
25
35
1
7