Test with a multimeter

Incandescent lamp (E10, 6 V 0.1 A)

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Now: Cold filament resistance

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Pin 1: Bottom contact (a) (a) Pin 2: Screw base (b) (b)

Red probe Not connectedBlack probe Not connected

Hold the probe and drag it to the tip of a leg. Tapping works too: first pick the probe, then the leg.

Set the range to Ω (resistance).

Measure step by step

A cold incandescent filament has about a tenth of its hot resistance; reading a few ohms is normal. The multimeter tells you whether the filament is broken; it cannot tell the brightness or the vacuum of the glass.

Take the measurement while the lamp is cold; do not touch the hot glass.

  1. 1Cold filament resistance
  2. 2Continuity