Electrical power tools must be___by 3-wire cord,___insulated, powered by a low-voltage transformer, or powered by a self-contained___.
A. Secured… partially… circuit
B. Grounded… double… battery
C. Wrapped… triple… control panel
D. Intersected… fully… generator
The correct answer and explanation is :
The correct answer is B. Grounded… double… battery.
Explanation:
Electrical power tools require specific safety measures to ensure they are used without causing harm to the operator or others nearby. Among these safety measures, grounding, insulation, and power supply types are critical components.
- Grounded by 3-wire cord:
- Grounding is a safety mechanism that prevents electrical shock by providing a safe pathway for electricity to flow into the ground in case of a short circuit or equipment failure. Electrical power tools must be grounded through a 3-wire cord, which includes a grounding wire (usually the third prong on the plug). This ensures that if a fault occurs, the electricity will be safely discharged rather than shocking the user. A 3-wire cord includes the live wire (for power), neutral wire (to complete the circuit), and a grounding wire for safety.
- Double insulated:
- Double insulation is a safety feature that isolates electrical parts from the outer casing of the tool to prevent electric shock. Tools with double insulation do not require a grounding conductor (grounding is still preferable but not mandatory for these tools), as the insulation effectively prevents the user from contacting live parts. Double insulation typically involves two layers of insulating material around electrical components, further enhancing the tool’s safety.
- Powered by a low-voltage transformer or self-contained battery:
- Electrical power tools can be powered by a low-voltage transformer or self-contained battery, both of which reduce the risk of electric shock and are safer alternatives to tools powered directly from a standard electrical outlet. A self-contained battery offers portability and reduces reliance on wired connections, which minimizes the chance of tripping over cords or being exposed to faulty wiring.
These safety features—grounding, double insulation, and a safe power supply—collectively help ensure that electrical power tools are safe for use in various work environments.