For large numeric displays these modules offer the optimum in visibility, reliability and economy. Consisting of 7 electromagnetic operated light reflecting segments, the module can display the digits 0-9, plus a limited selection of alpha characters. The character heights available are 100mm – 630mm (4″ – 25″). Standard colors are white and yellow. There are also available other symbols useful for sign construction like dots, colons, minus symbols, etc in all sizes.

Principle of operation

Electromagnetic displays work on a principle of reflected light. The selected flip element changes position according to the controlled change in the magnetic field of a closely coupled electromagnetic coil. No energy is needed to keep this state. This state is kept by internal magnetic memory.

The control signal simply reverses the direction of the current pulse through the coil that reverses the magnetic field of the coil. The flip element remains in the position to which it was last turned until the coil field is reversed by another current pulse.


The fluorescent, light-reflecting segments provide excellent visibility a wide range of ambient light conditions. Visibility increases with an increase in the ambient light level.


There are no lamps to burn out and no mechanical linkages to wear out. Each segment rotates on a stainless steel pivot for maximum reliability. The modules are highly resistant to shock and vibration which makes them also suitable for portable scoreboards and traffic control displays in high vibration environments.


Power is only required to change the data displayed. Inherent magnetic memory in each segment retains the display indefinitely without power being applied.

Typical applications include

  • sport signs
  • highway signs
  • passenger information signs
  • advertising signs
  • clocks / thermometers
  • gas price totems


Technical data

character format: seven segment
driving voltage: 24V for 100-450mm (+50% -10%)
36V for 630mm (+50% -10%)
max driving current: approx. 0.5A per segment
operating temperature: -40°C to +75°C
(ventilation required)
relative humidity: max 95% non-condensing
power required to keep information: ZERO
shock resistance: 10G 50ms
vibration resistance: amplitude ±1mm 5-13.3Hz
acceleration: 6.8 m/s² 13.2-100Hz
impact resistance: 10G 6ms, 1000 impacts
type: 4" 6" 7.5" 9" 12" 18" 25"
character height: 100mm155mm190mm250mm280mm450mm630mm
character width: 56mm100mm105mm140mm150mm250mm350mm
module height: 140mm178mm215mm270mm305mm473mm654mm
module width: 65mm 119mm130mm161mm175mm273mm374mm
module depth: 38mm50mm50mm50mm50mm56mm76mm
weight: 0,13kg0,50kg0,65kg0,7kg0,85kg1,25kg3,1kg
average life expectancy (operations): 30mln30mln30mln30mln30mln20mln20mln
lenght of control pulse: 50ms90ms90ms90ms90ms120ms250ms
coil resistance: 56Ω53Ω53Ω53Ω53Ω50Ω26Ω



  • In case of applications requiring very firm support of flags (for example timer with 1s change) it is advised to use version with screwed flags.
  • When ambient light increases, external illumination is no longer needed.
  • It is suggested to illuminate the module from below in order to illuminate light reflections.
  • In daylight, external illumination is not needed.
  • Pulse repetition rate should be such that max. coil temperature is not exceeded.
  • Next pulse should occur in such a time that energy from a coil can dissipate.
  • White colour is NOT fluorescent.
  • Cover plates for larger sizes are optional.

Outdoor applications

Requires weatherproof enclosure, the modules should be protected from the temperatures extremes created by sun-loading on the display enclosure.




Outdoor price signs

Outdoor price sign






Large 7-segment displays



Product brochure:

Large 7-segment display – general description
electromagnetic_large_7segment_display.pdf, 477KB