PHYSICAL properties of ballasts!

Although the design and structure of ballast differs according to their purpose of use and specifications, there are some general characteristics which are common in all types of ballasts. Some important properties are as follows:-

Most electronic ballast manufacturers prefer making ballasts from plastics. The plastic case makes them lightweight and also inexpensive. However plastic being an insulator does not efficiently handles heat. For high temperatures, metal ballasts can be useful.

Modern ballasts have a very compact design making them smaller in dimensions. Typically ballast may be around 1.5 inches long, however high power ballasts can be unusually high.

Electronic ballasts are made from solid state circuitry and therefore are significantly lighter in weight than metallic ballasts. However some potted electronic ballasts can be weightier than metallic ballasts. Metallic ballasts have a magnetic core which makes them heavier.

Electronic ballasts are completely noise proof. Since they are solid state devices, there is no sound produced while in operation. On the other hand, metallic ballasts produce a peculiar humming buzz caused by the vibration of the magnetic core. Electronic ballast manufacturers’ use ranges to define the amount of average ambient sound in decibels that are generated by their ballasts.

Flickering is caused when output light gets modulated while operating on AC current. Flickering can cause strain in the eyes and even headaches. The efficiency of ballast is also gauged according to its ability to prevent flicker. Ballasts refresh the phosphorus of fluorescent bulbs so rapidly that flickering is hardly noticed.