SUREBRAND WIRE WOUND RESISTOR SCF

Ceramic Encased Axial Lead with Fusible Rating Wire Wound Resistor'SURE'provides fusible resistor which fuse or blow if they are subjected to an abnormal spike of voltage / current. SCF Series is a low cost resistor fusible resistor which provides circuit protection for overload or component failure. The resistor will open quickly under continuous load and prevent circuit board from damage and hazards.High Power dissipation in small volumeHigh surface insulation propertyCompletely fire proof and welded constructionAvailable in PCB type and capacitor type terminalsFormed leads available on requestLow inductance type available on requestLong leads (50 mm/65 mm) also available for vertical mountingSCF: The resistor element is a resistive wire, which is wound, on ceramic rod. Tinned copper leads are connected to the caps by welding. The resistor body is housed in a rectangular ceramic case with a special inorganic potting which is non-flammable, will not melt even at high overloads and is resistant to most commonly used cleaning solvents and moisture.The power that the resistor can dissipate depends on the operating temperature; see belowSCFNOTE :Fusible resistors are not standard resistor types and each type of fusible resistor must be designed to suit a particular application.Data required to design a fusible resistor are:The type you require -Ceramic Encased or Axial Lead TypeResistance in ohms.Power rating in terms of watts.Tolerance.Fusing current - The current at which the resistor must fuse or blow.Fusing time - The duration within which the resistor must fuse or blow, on being subjected to the fusing current.At SURE if no special data is provided, a fusible resistor can be made as per the following chart :FUSING CHARACTERISTICS :TYPICAL APPLICATIONS :As mentioned previously a fusible resistor is a dual purpose component -(a) In normal conditions it functions as a resistor.(b) In high overload conditions it acts as a fuse/safety device.In some countries all types of ceramic encased type resistors are wrongly called as fusible resistors. It must be clearly understood that fusible resistors are special purpose, specially designed resistors and are produced mainly in two configurations -(a) Ceramic encased type(SCF)and(b) Flame retardant silicone coated axial lead type.(SSF)