What is the minimum torque for screw-type pressure terminals used with 14 AWG or smaller copper conductors in motor controllers?

What is the minimum torque for screw-type pressure terminals used with 14 AWG or smaller copper conductors in motor controllers?

• A. 7
• B. 10
• C. 12
• D. 20

Answer: (A)

The essential idea is to apply the right tightening force to screw-type pressure terminals so the conductor is held securely with good electrical contact without causing damage. For 14 AWG or smaller copper conductors in motor controllers, the minimum torque is seven inch-pounds. This level provides enough clamping pressure to maintain a low-contact-resistance connection and resist loosening from vibration and heat, while avoiding crushing the insulation or deforming the conductor strands. Tightening more than this on small conductors can harm insulation, deform the wire, or strip the screw, which can create new failure modes. Use a torque tool and follow the manufacturer’s table to ensure you reach at least seven inch-pounds for these conductors.

The essential idea is to apply the right tightening force to screw-type pressure terminals so the conductor is held securely with good electrical contact without causing damage. For 14 AWG or smaller copper conductors in motor controllers, the minimum torque is seven inch-pounds. This level provides enough clamping pressure to maintain a low-contact-resistance connection and resist loosening from vibration and heat, while avoiding crushing the insulation or deforming the conductor strands. Tightening more than this on small conductors can harm insulation, deform the wire, or strip the screw, which can create new failure modes. Use a torque tool and follow the manufacturer’s table to ensure you reach at least seven inch-pounds for these conductors.