MASTER-BILT 23-00349

BALLAST PREHEAT LAMP ADVANCE

An electrical ballast is a device that limits the current through an electrical load. These are most often used when a load (such as an arc discharge) has its terminal voltage decline when current through the load increases. If such a device were connected to a constant-voltage power supply, it would draw an increasing amount of current until it is destroyed or causes the power supply to fail. To prevent this, a ballast provides a positive resistance or reactance that limits the current. The ballast provides for the proper operation of the negative-resistance device by limiting current. Series resistors are used as ballasts to control the current through LEDs.

Heat lamps are similar to regular incandescent lamps (see below) but produce higher levels of infrared radiation. This creates more radiant heat, proving to be more useful as a source of warmth than a regular lamp. There are two kinds of heat lamps, red lamps and frosted/clear lamps. They function identically in terms of heat production, but the red lamp is designed to produce less visible light. Heat lamps are widely used in foodservice to prevent freshly prepared, hot dishes from cooling down before being delivered to the customer.

A replaceable component that produces light from electricity is called a lamp or a bulb. Lamps are commonly called "light bulbs". A wide variety of lamps/bulbs are used in restaurant equipment from refrigerators to merchandisers, and ovens to orbital mixers. Lamps usually have a base made of ceramic, metal, glass, or plastic, which secures the lamp in the socket of a light fixture. The electrical connection to the socket may be made with a screw-thread base, two metal pins that fit into a receiving clamp, two metal caps or a bayonet cap. The three main categories of electric lights are:

• Incandescent lamps, which produce light by a filament heated white-hot by electric current
• Gas-discharge lamps, which produce light by means of an electric arc through a gas
• LED lamps, which produce light by a flow of electrons across a band gap in a semiconductor.

A "sensing bulb" is the temperature sensing device (probe) of a thermometer, RTD, or thermistor. The 'bulb' refers to its shape and has nothing to do with lighting.