Cables And Wiring Length - Mitsubishi Electric 700 Series Instruction Manual

2.2.3

Cables and wiring length

(1) Applicable cable size
Select the recommended cable size to ensure that a voltage drop will be 2% or less.
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.
Three-phase 200V class (when input power supply is 220V)
Applicable Inverter
Model
FR-E720-0.1KNF to 0.75KNF
FR-E720-1.5KNF, 2.2KNF
FR-E720-3.7KNF
FR-E720-5.5KNF
FR-E720-7.5KNF
FR-E720-11KNF
FR-E720-15KNF
Three-phase 400V class (when input power supply is 440V)
Applicable Inverter
Model
FR-E740-0.4KNF to 3.7KNF
FR-E740-5.5KNF
FR-E740-7.5KNF
FR-E740-11KNF
FR-E740-15KNF
∗1
The cable size is that of the cable (HIV cable (600V class 2 vinyl-insulated cable) etc.) with continuous maximum permissible temperature of 75°C. Assumes
that the surrounding air temperature is 50°C or less and the wiring distance is 20m or less.
∗2
The recommended cable size is that of the cable (THHW cable) with continuous maximum permissible temperature of 75°C. Assumes that the surrounding air
temperature is 40°C or less and the wiring distance is 20m or less. (Selection example for use mainly in the United States.)
∗3
The recommended cable size is that of the cable (PVC cable) with continuous maximum permissible temperature of 70°C. Assumes that the surrounding air
temperature is 40°C or less and the wiring distance is 20m or less. (Selection example for use mainly in Europe.)
∗4
The terminal screw size indicates the terminal size for R/L1, S/L2, T/L3, U, V, W, and a screw for earthing (grounding).
A screw for earthing (grounding) of the FR-E720-15KNF is indicated in ( ).R/L1, S/L2P/N/
NOTE
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.
The line voltage drop can be calculated by the following formula:
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.
Crimping
Terminal Tightening Terminal
Screw Torque
R/L1
Size N·m
∗4
S/L2 U, V, W
T/L3
M3.5 1.2 2-3.5 2-3.5
M4 1.5 2-4 2-4
M4 1.5 5.5-4 5.5-4
M5 2.5 5.5-5 5.5-5
M5 2.5 14-5 8-5
M5 2.5 14-5 14-5
M6(M5) 4.4 22-6 22-6
Crimping
Terminal Tightening Terminal
Screw Torque
R/L1
Size N·m
∗4
S/L2 U, V, W
T/L3
M4 1.5 2-4 2-4
M4 1.5 5.5-4 2-4
M4 1.5 5.5-4 5.5-4
M4 1.5 5.5-4 5.5-4
M5 2.5 8-5 8-5
1000
Main circuit terminal specifications
Cable Size
2
HIV Cables, etc. (mm )
AWG
∗1
R/L1 R/L1
Earthing
S/L2 U, V, W S/L2
cable
T/L3 T/L3
2 2 2 14
2 2 2 14
3.5 3.5 3.5 12
5.5 5.5 5.5 10
14 8 5.5 6
14 14 14 6
22 22 14 4
Cable Size
2
HIV Cables, etc. (mm )
AWG
∗1
R/L1 R/L1
Earthing
S/L2 U, V, W S/L2
cable
T/L3 T/L3
2 2 2 14
3.5 2 3.5 12
3.5 3.5 3.5 12
5.5 5.5 8 10
8 8 8 8
PVC Cables, etc. (mm
∗2
∗3
R/L1
Earthing
U, V, W S/L2 U, V, W
cable
T/L3
14 2.5 2.5 2.5
14 2.5 2.5 2.5
12 4 4 4
10 6 6 6
8 16 10 6
6 16 16 16
4 25 25 16
PVC Cables, etc. (mm
∗2
∗3
R/L1
Earthing
U, V, W S/L2 U, V, W
cable
T/L3
14 2.5 2.5 2.5
14 4 2.5 4
12 4 4 4
10 6 6 10
8 10 10 10
17
2
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2
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