Final answer:
The three basic means of safeguarding machinery are circuit breakers and fuses, the three-wire system, and ground fault interrupters. These devices prevent thermal hazards and electric shocks by interrupting excessive currents and detecting the loss of current to unintentional paths.
Step-by-step explanation:
Three basic means of safeguarding machinery are:
- Circuit breakers and fuses: These devices interrupt excessive currents to prevent thermal hazards. They are designed to break the circuit when the current exceeds a certain limit, protecting the machinery from overheating.
- The three-wire system: This system utilizes live/hot, neutral, and earth/ground wires to guard against thermal and shock hazards. The neutral wire and the case of the appliance are grounded to prevent electrical accidents.
- Ground fault interrupter (GFI): GFIs are designed to prevent electric shocks by detecting the loss of current to unintentional paths. They quickly cut off the power supply to avoid accidents.
These safety measures are crucial in ensuring the smooth operation of machinery while minimizing the risk of electrical accidents.