Safety and work practicesQuestion 290 of 1506

Why should the disconnect used for lock-out be separate from the regular on/off switch?

It is used only to secure the system in a Zero Energy State
Regular switches are not able to carry fault current at all
It allows the machine to run at a slower speed
It saves wire in the control circuit wiring

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Correct answer: It is used only to secure the system in a Zero Energy State

A dedicated safety disconnect is not operated for normal use, so its open position means the system is secured.

Source: Troubleshooting Motors and Controls (Dickson-Self), 1.1: Safety

Questions last reviewed: 18 October 2026

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