3 Wiring and Connection3.1.2 Main Circuit Wire3-63.1.2 Main Circuit WireThis section describes wires used in the main circuit.(1) Wire TypesUse the following type of wire for main circuit.The following table shows the wire sizes and allowable currents for three wires.Use wires with specifications equal to or less than those shown in the table.Note: These are reference values for 600-V-grade, heat-resistant, PVC-insulated wire.• The specified wire sizes are for use when the three lead cables are bundled and whenthe rated electric current is applied with a surrounding air temperature of 40°C.• Use a wire with a minimum withstand voltage of 600 V for the main circuit.• If cables are bundled in PVC or metal ducts, take into account the reduction of theallowable current.• Use a heat-resistant wire under high surrounding air or panel temperatures, wherepolyvinyl chloride insulated wires will rapidly deteriorate.Cable Type Allowable Conductor Temperature(°C)Symbol NameIV 600 V polyvinyl chloride insulated wire 60HIV 600 V grade heat-resistant polyvinyl chloride insulated wire 75Nominal CrossSection Diameter(mm 2)AWG SizeConfiguration(Number of Wires/mm)ConductiveResistance (Ω/km)Allowable Current at Surrounding AirTemperature (A)30°C 40°C 50°C0.5 (20) 19/0.18 39.5 6.6 5.6 4.50.75 (19) 30/0.18 26 8.8 7 5.50.9 (18) 37/0.18 24.4 9 7.7 61.25 (16) 50/0.18 15.6 12 11 8.52 (14) 7/0.6 9.53 23 20 163.5 (12) 7/0.8 5.41 33 29 245.5 (10) 7/1.0 3.47 43 38 318 (8) 7/1.2 2.41 55 49 4014 (6) 7/1.6 1.35 79 70 5722 (4) 7/2.0 0.85 91 81 6638 (1) 7/2.6 0.49 124 110 9360 (2/0) 19/2.0 0.30 170 150 127100 (4/0) 19/2.6 0.18 240 212 179
