Precision Metal Film Resistors Welwyn Components RC series CECC released products with low TCRs over a wide resistance range Resistance tolerance down to 0.05% Express delivery available Low noise and negligible voltage coefficient Electrical Data RC55 RC65 RC70 Notes Commercial Power rating at 70C watts 0.25 0.5 1.0 Resistance range ohms 1R to 4M 1R to 4M 1R to 10M Limiting element voltage volts 350 350 500 Isolation voltage volts 500 500 700 TCR (20 to +70C) & codes ppm/C 5(V), 10(T), 15(Y), 25(D), 50(C) & 100(Z) See resistance Resistance tolerance % 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions Approved CECC 40101-004 H J K K L Power rating at 70C watts 0.063 0.125 0.25 0.25 0.5 Resistance range ohms 1R to 1M 1R to 1M 1R to 1M 10R to 1M 10R to 1M Limiting element voltage volts 200 200 250 250 350 Isolation voltage volts 280 280 350 350 500 TCR & codes ppm/C 15(Y), 25(D), 50(C) & 100(Z) See resistance Resistance tolerance (code) % 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions Approved CECC 40101-804 A B B C Power rating at 70C watts 0.125 0.25 0.25 0.5 Resistance range ohms 1R to 1M 1R to 1M 10R to 1M 10R to 1M Limiting element voltage volts 200 250 250 350 Isolation voltage volts 280 350 350 500 TCR & codes ppm/C 15(T), 25(E) & 50(C) See resistance Resistance tolerance (code) % 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions Standard values E24, E96 preferred Any value Thermal impedance C/watt 110 70 60 to order Ambient temperature range C -55 to +155 General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. A subsidiary of All information is subject to Welwyns own data and is considered accurate at time of going to print. TT electronics plc Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info welwyn-tt.com Website: www.welwyn-tt.com Issue B 03.02 173Precision Metal Film Resistors Welwyn Components RC series Physical Data Dimensions (mm) & Weight (g) PCB Min. mounting Bend Type L max D max f min d nom centres Radius Wt. nom d RC55 7.2 2.5 30 0.6 10.2 0.6 0.24 D L f RC65 10.0 3.7 30 0.6 12.7 0.6 0.40 RC70 15.5 5.5 30 0.8 18.4 1.2 1.15 Marking Construction Type reference, TCR code, resistance value and A metal film is deposited onto a high quality ceramic former. tolerance code. Nickel-plated steel caps are force fitted to the former and termination wires are welded to the caps. The resistance values conform to IEC 62. The resistor is adjusted to value by a helical cut in the film Solvent Resistance and the body is protected with a specially formulated epoxy The body protection and marking are resistant to all normal coating. industrial cleaning solvents suitable for printed circuits. 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. Performance Data CECC 40101-004 CECC 40101-804 *Actual Performance Requirements Requirements Maximum Typical Load at commercial rating: 1000 hours at 70C R% 0.3 0.1 Load at CECC rating: 1000 hours at 70C R% 0.5 0.5 0.3 0.05 Dry heat: 1000 hours at 155C R% 0.5 0.5 **1.0 0.15 Shelf life: 12 months at room temperature R% Not specified Not specified 0.1 0.03 Derating from rated power at 70C Zero at 155C 50% at 125C Short term overload R% 0.1 0.1 0.1 0.02 Climatic R% 0.5 0.5 0.3 0.1 Climatic category 55/155/56 55/125/56 55/155/56 Long term damp heat R% 0.5 0.5 0.5 0.1 Temperature rapid change R% 0.1 0.1 **0.2 0.05 Resistance to solder heat R% 0.1 0.1 0.06 0.03 Vibration and bump R% 0.1 0.1 0.06 0.02 Noise (in a decade of frequency) V/V Not specified Not specified 1.0 0.1 Voltage coefficient of resistance ppm/V Not specified Not specified <1 Note: *An 0.01 ohm addition to be added to the performance claims of all resistors <10R. ** All products within the specified approved range meet CECC requirements. Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info welwyn-tt.com Website: www.welwyn-tt.com Issue B 03.02 174