Enclosures serve the dual purpose of protecting personnel from incidental contact with the enclosed electrical equipment and protecting the enclosed equipment against specified environmental conditions. Enclosures are rated for use in specific environmental conditions by international and national standard organizations. The major international rating system uses the IEC Enclosure Classification Designation.

Founded in 1906, the International Electrotechnical Commission (IEC) is the global organization that prepares and publishes international standards for all electrical, electronic and related technologies. The membership consists of more than 60 participating countries, including Canada and the USA. Central office of IEC is located in Geneva, Switzerland. IEC web site is http://www.iec.ch IEC International Standard 60529 “Degrees of protection provided by enclosures (IP Code)” describes a system for classifying the degree of protection by the IP Code.

IP (International Protection) Code is a coding system described by IEC International Standard 60529 “Degrees of protection provided by enclosures (IP Code)”. IP Code indicates the degree of protection provided by enclosure against access to hazardous parts, ingress of solid foreign objects, ingress of water and to give additional information in connection with such protection. IP code is arranged in the following way:

The higher protection classification always takes precedence over the lower classification.

Example: an enclosure with IP 67 Code;

- Totally protects persons against access to hazardous parts (tested with a wire of 1,0 mm diameter)
- Dust-tight enclosure, totally protects the equipment inside the enclosure against dust (tested by the talcum powder in suspension in a closed test chamber under pressure)
- Waterproof enclosure, totally protects equipment inside the enclosure against water penetration (tested by completely immersing the enclosure in water tank for 30 minutes 1 m deep)

High efficiency, high frequency electronic ballasts offer enhanced lighting performance and energy savings. Modern electronic ballasts operate at a frequency above 20,000 Hz. This high frequency operates lamps more efficiently (10-15% more light output) and eliminates the 60 cycle hum and visible flicker normally associated with electromagnetic ballasts.

Electronic ballasts generate less waste heat than comparable magnetic ballasts. Typically, electronic ballasts will operate 20-30°C cooler than it’s magnetic counterpart. Most ballast manufacturers design electronic ballasts for optimum life at a case temperature less than 70°C. Cooler operation results in longer ballast life and reduced air-condition requirements.

Fluorescent lamps are inherently more difficult to start at low temperatures. All ballasts have limitations as to their ability to start lamps at low ambient temperatures. But electronic ballasts can ignite lamps at 0°F(-18°C) compare to 50°F(0°C) by magnetic ballasts.

Electronic ballasts operate at sound levels lower than electromagnetic ballasts (up to 75% quieter).

Instant Start(IS) electronic ballasts are the most popular type of electronic ballast today because they provide maximum energy savings and they start lamps without delay or flashing. Instant Start ballasts provide a high initial voltage (typically 600V for F32T8 lamps)to start the lamp. This high voltage is required to initiate discharge between the unheated electrodes of the lamp. However, the cold electrodes of lamps operated by an instant start ballast may deteriorate more quickly than the warmed electrodes of lamp operated by program start ballast. Lamps operated by instant start ballasts will typically withstand 10,000-15,000 switch cycles.

Since they do not provide lamp electrode heating, Instant Start ballasts consume less energy than comparable program start ballasts. As a result, they provide the most energy efficient solution to fluorescent lamp ballasting.

Program Start(PR) electronic ballast provide maximum lamp life in frequent starting conditions (up to 50,000 starts). Program Start ballast precisely heat the lamp cathodes to 700°C prior to lamp ignition. This puts the least amount of stress on the lamp electrodes, resulting in maximum lamp life regardless of the number of lamp starts. Program Start electronic ballasts are the best solution for use in facilities with occupancy switches.