Neon-lamp holders A lot of industrial electronic equipment uses neon lamps to indicate when they have been energized from the mains. If the lamp fails to glow, it means something is wrong with the supply circuit, the equipment, or the indicator itself. The neon lamps used are quite small and housed in holders 5 mm to 10 mm in diameter.
The excess-3 code for a given decimal number is determined by adding ‘3’ or “0011” to each decimal digit in the given number.
While estimating the overhead lines, the first and last pole is always earth connected and after every 3rd electrical pole, the fourth pole is earthed. Therefore, the approximate number of required ground set = 4
We use universal motors in mixer grinders. Universal motors can run both on a.c. and d.c.
The universal motor works on the same principle that DC series motor works. DC series motor has the characteristics of operating at high-speed when there is no load and operating at low-speed when the load is applied. It has high starting torque characteristics.
So it is used in mixers, where initially we put some load at starting.
The amount of flux produced by the magnet indicates the strength of the magnet. The more the magnetizing force (MMF), the more is the flux produced. The more the opposition to the flux path (i.e., reluctance or magnetic resistance) less is the flux produced. This relationship is expressed as
Flux = MMF/ Reluctance
Reluctance is the opposition offered by the material in the flux path to the establishment of the flux. The reluctance in a magnetic circuit is similar to the resistance in an electric circuit. Reluctance is the inverse of permeance.
MMF = Flux/Permeance