Incandescent lamp (E10, 6 V 0.1 A) · Exterior view
Tungsten filamentGlass bulb · Ø 11 mmSocket (lamp holder) · E10Connection pin
Glass bulb, E10 metal screw and an insulated center contact at the bottom
E10 screw diameter 10 mm; glass diameter ≈ 10 mm, length ≈ 23 mm (depends on the model)
Outputs

Incandescent lamp (E10, 6 V 0.1 A)

In simple terms
What is this?

A small glass bulb with a thin wire glowing inside. As the wire heats up it turns red and gives off light.

What is it for?

Gives light when current passes; the old way of showing by eye that a circuit works.

Where do you see it?

In old incandescent bulbs and old flashlights.

How do you spot it?

A small glass bulb with a screw-threaded metal body below it; it has two contacts: the tip at the bottom and the screw.

Caution:

Do not go above the voltage on the label, the wire burns; a lit bulb is very hot, do not touch it.

Technical definition

The thin tungsten filament inside the glass bulb heats up with current and gives off light. It is not a semiconductor like an LED and has no polarity. When cold, the filament’s resistance is about one tenth of its hot value; at switch-on it briefly draws a high current.

Voltage6 V
Current0.1 A
Power0.6 W
Schematic symbol Same in IEC and ANSI

IEC 60617: the drawing style used in Türkiye and Europe.

Pins 2
1Bottom contact (a)The socket’s center contact; nonpolara
2Screw base (b)The socket’s outer contact; insulated from the bottom contactb
Features typical
Rated voltage
6 V DC or 6 V RMS AC
Rated current
0.1 A
Power
0.6 W
Hot resistance
≈60 Ω (at the rated point)
Cold resistance
≈6 Ω; hot value about 10 times
Inrush current
For a short time about 10 times the rated current
Socket
E10, two separate contacts
Example part
E10 miniature bulb, 6 V 0.1 A
Common mistakes
Mistaking a cold measurement for a faultThe low resistance measured with a multimeter is normal. The filament’s resistance rises as it heats up.
Increasing the voltagePowering a 6 V bulb with 9 V overheats the filament and shortens its life. Keep to the rated voltage.
Driving directly from a pinUse a suitable transistor, MOSFET or relay for running and inrush current; do not touch the hot glass.

Test with a multimeter

Test whether this part is good with the multimeter on the measurement screen.

Take a measurement
Where it is used
Low-voltage light indicatorExperiment on resistance change with heatLighting through a relay
Related lessons
Ohm’s law
Module 1 · From zero to your first circuitMeasuring current and the fuse
Module 2 · Measuring with a multimetersoonDriving a relay and the flyback diode
Module 4 · Diode and transistorsoon
Try it in the Lab