Definition

Noun: A mechanical component, specifically a conductive arm, that moves across a series of stationary electrical contacts and stops to make a connection at a designated terminal or outlet. It is a key part in certain types of electrical switches or selectors.

Usage

The term "wiper arm" is used to describe the moving part in a rotary switch, potentiometer, or similar electromechanical device. It "wipes" across the contacts.

Examples

• The technician adjusted the wiper arm to ensure proper contact with the terminal.
• A faulty wiper arm can cause intermittent signal loss in the circuit.
• The selector switch operates by rotating the wiper arm to different fixed contacts.

Advanced Usage

• In automotive contexts, the term is almost exclusively used for the mechanical arms that move windshield wiper blades. However, in electrical engineering, its primary meaning refers to the contacting arm in a switch or variable resistor.
• The position of the wiper arm determines the selected circuit or the resistance value.

Variants and Related Words

• Wiper (noun): Often used as a shorter form for "wiper arm," especially in electrical diagrams.
• Contact Arm (noun): A more general synonym.
• Rotary Switch (noun): A common device that contains a wiper arm.

Synonyms

• Contact arm
• Selector arm
• Moving contact

Notes on Different Meanings

1. Electrical/Mechanical Engineering: A conductive arm in a switch or potentiometer.
2. Automotive: The linkage arm that physically moves a windshield wiper blade back and forth. (This is a distinct, compound application of the word "wiper").

Related Phrases/Idioms

• Wiper arm travel: Refers to the path or range of motion of the wiper arm.
• Wiper arm contact resistance: The electrical resistance at the point where the wiper arm touches the fixed contact.

Noun

1. contact consisting of a conducting arm that rotates over a series of fixed contacts and comes to rest on an outlet