Mitsubishi Electric 800 Series Assembly & Installation Manuallines page 17

2.3 Wiring fundamentals
2.3.1 Applicable cables and the wiring length
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 speed.
The following tables indicate a selection example for the wiring length of 20 m.
690 V class (690 V input power supply)
Applicable
Terminal
Tightening
inverter type
screw
FR-A870-
*3
size
M10
02300
M10
02860
*1
It is the gauge of a cable with the continuous maximum permissible temperature of 75 °C (THHW cable).
It assumes a surrounding air temperature of 40 °C or lower and in-enclosure wiring.
(For use in the United States or Canada, refer to page 46.)
*2
It is the gauge of a cable with the continuous maximum permissible temperature of 70 °C (PVC cable).
It assumes a surrounding air temperature of 40 °C or lower and in-enclosure wiring.
(Selection example for use mainly in Europe.)
*3
The terminal screw size indicates the terminal size for R/L1, S/L2, T/L3, U, V, W, PR, P/+, N/–, and a screw for earthing (grounding).
*4
When using stranded wire, strip back 40 mm of the sheath.
*5
When using flexible wire, strip back 40 mm of the sheath and crimp the wire with a ferrule.
*6
Use copper wire.
*7
Use stranded wire or flexible wire with a ferrule. Do not use solid wire. Do not use flexible wire without a ferrule.
Commercially available ferrules (as of January 2018)
Manufacturer: Klauke
2
Ferrule part No.
Cable gauge (mm )
150 8440V
185 8540V
The line voltage drop can be calculated by the following expression:
3 × wire resistance [m /m] × wiring distance [m] x 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 tightened too loosely can cause a short circuit or malfunction.
A screw that has been tightened too tightly can cause a short circuit or malfunction due to the unit breakage.
AWG/MCM
torque
*4
Stranded
[Nm]
R/L1, S/L2,
U, V, W
T/L3
20 ±2 4/0 4/0
20 ±2 300 300
40 mm
Crimping tool name
EKM6022L
1000
Cable gauge
*1
Stranded
Earth
(ground)
R/L1, S/L2,
U, V, W
cable
T/L3
2/0 150
3/0 185
Tool model No.
Battery
RAL1
*6, *7
2 *2
PVC cables, etc. (mm )
*4 *5
Flexible with ferrule
R/L1, S/L2,
U, V, W
T/L3
150 150 150
185 185 185
Charger Crimping die
AE22150
LGL1
AE22185
WIRING
Earth
(ground)
cable
70
95
11