Fluorescent Lamps electronic starter and ignition schematic

-

Standard conventional and circular fluorescent lamps with filaments can be ignited easily and much more quickly by using Thyristors instead of the mechanical starter switch, and solid state Thyristors are more reliable.
Thyristors produce a pure solid state igniting circuit with no mechanical parts in the fluorescent lamp fixture. Also, because the lamp ignites much faster, the life of the fluorescent lamp can be increased since the filaments are activated for less time during the ignition. The Thyristor ignition eliminates any audible noise or flashing off and on which most mechanical starters possess.

Figure shows a circuit for igniting a fluorescent lamp with 240 V line voltage input using Triac and DIAC networks.



Figure illustrates a schematic using a SIDAC phase control network to ignite a 240 V ac fluorescent lamp. The one major change is that two K2400E devices in series are used to accomplish high firing voltage for a fluorescent lamp.

Source: Littelfuse

Popular posts from this blog

Washing machine system diagram front loading parts

-
Image
Washing machine system diagram front loading parts:  1. Electronic board 2. Detergent dispenser 3. Tub suspension spring 4. Tub 5. Pressure switch 6. Detergent entry tube 7. Tube between solenoid and detergent dispenser 8. Solenoid 9. Water fill hose 10. Rear counterweight 11. Drum pulley 12. Bearings 13. Heating element with NTC 14. Drain hose 15. Motor pulley 16. Motor 17. Damper 18. Drain pump 19. Pressure chamber 20. Drain filter 21. Tube between tub and filter body 22. Eco-ball 23. Door safety interlock 24. Door 25. Door seal 26. Front counterweight In a washing machine, the dirt in the fibres is removed by a combination of mechanical and chemical  actions. The solenoid valve ducts water through the detergent dispenser, where it collects the detergent and passes  into the tub. The correct water level is controlled by one or more pressure switches. The fabrics loaded into the drum are maintained in constant movement
Read more

Tweeter loudspeaker burning protection schematic

-
Image
Many loudspeaker systems incorporate  PolySwitch devices for  overcurrent protection. By tripping  during high-current conditions and  resetting when no longer needed,  PolySwitch devices provide reliable  protection without the nuisance  and replacement costs  associated with fuses. The Problem Today’s speakers are generally  designed and sold independently  of amplifiers. Thus, mismatches  may occur, which can lead to damage.  Also, the advent of digital  recordings and compact discs  places extra burdens on sound  systems. Speaker damage can  result from a number of factors,  including the following situations: • High-power amplifiers used with  low-power speakers may simply  overdrive the speaker coils with  excessive power during sustained high volume. • Low-power amplifiers may be  overdriven so that clipping  occurs. This causes an upward  frequency shift of power that can  overload the tweeter. This problem  is especially common with  the wide dynamic ranges found  on compac
Read more