Ploy-fuse Seminar | Electrical Seminar Topic
Ploy-fuse Seminar
Current flow in a conductor always generates heat. Excess
heat is damaging to electrical components. Overcurrent protection devices are
used to protect conductors from excessive current flow. Thus protective devices
are designed to keep the flow of current in a circuit at a safe level to
prevent the circuit conductors from overheating.
A fuse is a one-time over-current protection device
employing a fusible link that melts (blows) after the current exceeds a certain
level for a certain length of time. Typically, a wire or chemical compound
breaks the circuit when the current exceeds the rated value.
A fuse interrupts
excessive current so that further damage by overheating or fire is prevented.
Wiring regulations often define a maximum fuse current rating for particular
circuits. Overcurrent protection devices are essential in electrical systems to
limit threats to human life and property damage. Fuses are selected to allow
passage of normal current and of excessive current only for short periods.
Polyfuse is a resettable fuse that doesn’t need to be
replaced like the conventional fuse. Many manufacturers also call it PolySwitch
or MultiFuse. Polyfuse are designed and made of PPTC material in thin chip
form. It is placed in series to protect a circuit. Polyfuse provide
over-current protection and automatic restoration.
