Definition
A precision resistor connected in series with a voltmeter to extend its measuring range. The multiplier resistor drops most of the applied voltage so that only a small, known fraction reaches the meter movement, allowing a low-range meter to safely read much higher voltages.
Plain English
A resistor placed in line with a voltmeter so the meter can measure higher voltages than it could on its own. It absorbs most of the voltage and lets the meter see only a small share.
Context Anchor
Seen in aircraft electrical-system discussions, especially when learning how voltmeters and analog electrical instruments are built or troubleshot.
Derivation
Called a 'multiplier' because it multiplies the voltage range the meter can read. A meter that natively reads 1 volt can, with the right multiplier resistor, read 10, 100, or 1,000 volts.
Why Pilots Care
Ensures cockpit instruments give accurate readings of battery, generator, and bus voltages critical for flight decisions.
Intuition Check
Do not read “multiplier” as meaning the resistor boosts voltage. Here it means the resistor helps the meter measure a larger voltage range safely.
Example Sentence 1
The voltmeter uses a multiplier resistor in series with the meter movement so it can safely read the full bus voltage.
Example Sentence 2
A failed multiplier resistor gave false low readings on the battery during the preflight electrical check.