Insulated electric cable

An insulated electric cable comprising:

• a core member formed by stranding a plurality of core wires, each of the core wires including a conductor and an insulating layer covering the conductor;
• a first coating layer which is formed of extruded resin covering the core member;
• a second coating layer covering the first coating layer;
• and
• a tape member disposed between the core member and the first coating layer in a state that it is wrapped around only the core member,
• wherein the insulating layer does not include magnetic powder,
• wherein the first coating layer covers only the core member and the tape member,
• wherein the second coating layer is formed by a flame-retardant polyurethane-based resin, and
• wherein the core member has two first core wires respectively being discrete from each other and having a same diameter as each other and two second core wires respectively having a second diameter different from that of the two first core wires, and
• the two second core wires are mutually stranded to form a subunit, and the subunit and the two first core wires are stranded to form the core member, and
• a cross-sectional area of each of the conductors is in a range of 0.18 to 3.0 mm2, and a cross-sectional area of a conductor of the first core wires is greater than that of the second core wires.