The 382 TR-5 Series subminiature fuse meets the following safety standard (IEC60127-3/IV) and is VDE & SEMKO approved and cULus recognized. Fuses are used in electronic lighting ballasts to protect against overcurrent and short circuit fault conditions. When individual lighting ballasts are protected, the faulty ballast is easily identified and prevents an entire string of ballasts from going off. This serves to not only reduce the labor costs in identifying the faulty ballast but also prevents a dangerous situation where large areas such as an office complex or factory floor could be "blacked out". U.S. commerical buildings typically operate with a line voltage of 227 Vac plus a 10% safety factor requiring protection components to be rated greater than 305V. The 382 Series TR-5 is certified up to 320Vac and is designed for use in board assembly processes. Due to its inherent small form factor, costs are optimized while space saving designs are possible.