EMC2-4R7K TT Electronics

Pulse Withstanding Fusible Flameproof Metal Film Resistors EMC Series UL1412 recognised* Failsafe 240V mains fusing Good pulse handling capability Small size for power rating UL94-V0 flameproof protection * Values 22R and above. UL file number E234469 Electrical Data EMC2 D Watts 2 Power rating at 70C Resistance range Ohms 4R7 68R TCR (25 to 75C) ppm/C 100 Isolation Voltage Volts 500 f L d Resistance Tolerance % 10, 20 Standard Values E12 Thermal Impedance C/Watt 82 Ambient temperature range -55 to +155 C Physical Data Dimensions (mm) & Weight (g) Type L max D max f min d nom PCB mount centres Min bend radius Wt. nom 10 4 27 0.8 18.4 1.2 0.55 EMC2 Construction The metal film is deposited onto a high purity ceramic rod. End caps are force fitted and termination wires are welded to the end caps. Finally, a cement protection is applied to the resistor body prior to marking with indelible ink. The cement protection is applied in a manner that leaves the terminations completely clear. This permits a well-defined body length (clean lead to clean lead dimension L). Terminations Material: Solder-coated copper wire Strength: The terminations meet the requirements of IEC 68.2.21 Solderability: The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 Solvent Resistance The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyns own test data and is considered accurate at time of print. A subsidiary of TT electronics plc Welwyn Components Limited Welwyn Electronics Park, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 822181 Fax: 01670 829465 Web: www.welwyn-tt.com 07. 08 Flammability The resistor coating is UL94-V0 rated and will not burn or emit incandescent particles under any condition of applied temperature or power overload. Marking EMC resistors are colour coded with five bands. Four of the bands indicate value and tolerance in accordance with IEC62. Parts with 20% tolerance have no fourth band. A fifth yellow band denotes constant voltage fusibility. Performance Data Maximum 5 Load at Rated Power: 1000hrs 70 C R% Shelf life: 12 months at room temperature R% 2 Derating from rated power at 70 C Zero at 155 C Climatic 3 R% Climatic Category 50/155/56 Temperature rapid change 0.5 R% Resistance to solder heat R% 0.5 Pulse Performance IEC61000-4-5 1.2/50 s Pulse Single Rectangular Pulse 10000 700 600 1000 500 400 100 300 200 100 10 0 0 10 20 30 40 50 60 70 1 Value (Ohms) 0.01 0.1 1 10 100 1000 10000 Pulse Duration (ms) Fusing Performance Fusing Characteristic (Constant Voltage) EMC resistors fuse open circuit at overload powers exceeding 60W within the time indicated on the Fusing Characteristic. Their fusing performance at 20 lower overload powers is not specified. 15 EMC resistors fuse safely in the event of a 115Vrms / 10 240Vrms overload (line / mains short circuit condition) without burning or emitting incandescent 5 particles. 0 After fusing, the resistance is at least 100 times 40 50 60 70 80 90 100 greater than the original nominal value. Initial Power (W) (4R7-8R2) (10R-68R) General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyns own test data and is considered accurate at time of print. A subsidiary of TT electronics plc Welwyn Components Limited Welwyn Electronics Park, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 822181 Fax: 01670 829465 Web: www.welwyn-tt.com 07. 08 Pk Voltage (V) Max. Fusing Time (s) Pk Power (W)