Resistors Cement Coated Cement Coated Welwyn Components Wirewound Resistors Wirewound Resistors W30 Series W30 Series Values down to 10m ohms Values down to 10m ohms Tolerance to 1% Tolerance to 1% Flameproof protection Flameproof protection Custom built to meet pulse requirements Custom built to meet pulse requirements Surface mount ZI-form option All Pb-free parts comply with EU Directive 2011/65/EU (RoHS2) Electrical Data W31 Notes Power rating at 25C watts 3.0 Power rating at 70C watts 2.5 Resistance range ohms 0R01 to 10K TCR (-55 to 155C) ppm/C See below Resistance tolerance % <R10: 5 >=R10: 1, 2, 5 Standard values E24 series preferred Other values to special order Thermal impedance C/watt 83 Ambient temperature range C -55 to 155 Limiting element voltage volts 100 TCR ppm/C R01: 1000 >R01 - R033: 500 >R033 - R091: 200 >R091 - 10R: 150 >10R: 100 Physical Data Maximum Dimensions (mm) and Weight (g) Type L max. D max. f min. d nom. Wt.nom. d D L W31 13 5.6 (note 1) 22.75 0.8 1.0 f < Note 1: 5.8 for values 0R1 Construction Marking A high quality ceramic substrate is assembled with W31 resistors are legend marked with type reference, interference fit end caps to which are welded the element resistance value and tolerance. Values are marked in accordance with IEC 62. to the body, providing an effective seal which is impervious to moisture, shock, vibration, fungus and salt spray. Solvent Resistance The body and marking are resistant to all normal industrial Terminations cleaning solvents suitable for printed circuits. Material Solder coated copper. Strength The terminations meet the requirements of Flammability IEC 68.2.21. The resistor coating will not burn under any condition of Solderability The terminations meet the requirements of applied temperature or component overload. IEC 115-1, Clause 4.17.3.2. General Note General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. BI Technologies IRC Welwyn TT Electronics reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyns own data and is considered accurate at time of going to print. A subsidiary of All information is subject to TT Electronics own data and is considered accurate at time of going to print. TT electronics plc www.ttelectronicsresistors.com 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 D 07.06 TT Electronics plc 10.16 99Cement Coated Cement Coated Wirewound Resistors Cement Coated Wirewound Resistors W30 Series Welwyn Components Wirewound Resistors W30 Series Welwyn Components W30 Series Performance Data Performance Data Maximum Typical Load: 1000 hrs 3 watts 25C R% 5.0 + .001 3.5 Maximum Typical 1000 hrs 2.5 watts 70C R% 5.0 + .001 3.5 Load: 1000 hrs 3 watts 25C R% 5.0 + .001 3.5 Dry heat: 1000 hrs at 200C R% 5.0 + .001 3.5 1000 hrs 2.5 watts 70C R% 5.0 + .001 3.5 Derating from room temperature see derating curve Dry heat: 1000 hrs at 200C R% 5.0 + .001 3.5 Short term overload 10 x rated power for 5 seconds R% 5.0 + .001 1.0 Derating from room temperature see derating curve ClimaticShort term overload 10 x rated power for 5 seconds RR%% 5.05.0 + + .001 .001 3.51.0 ClimaticClimatic category R% 5.0 + .001 55/200/56 3.5 Climatic category 55/200/56 Long term damp heat: 56 days R% 3.0 + .001 1.0 Long term damp heat: 56 days R% 3.0 + .001 1.0 Temperature rapid change R% 2.0 + .001 1.5 Temperature rapid change R% 2.0 + .001 1.5 Resistance to solder heat R% 5.0 + .001 2.0 Resistance to solder heat R% 5.0 + .001 2.0 Vibration and bump R% 5.0 + .001 2.0 Vibration and bump R% 5.0 + .001 2.0 Voltage proof volts 500 min Voltage proof volts 500 min Pulse handling Data available by request Pulse handling Data available by request W31 Series Derating Curve 130 W31 Series Derating Curve Application Notes 120130 110 Application Notes 120 The terminations should not be bent closer than 1.6mm from 100110 90100 The terminations should not be bent closer than 1.6mm from the body, and the recommended minimum bend radius is 8090 the body, and the recommended minimum bend radius is 1.2mm. 80 70 1.2mm. 70 60 60 50 Care must be taken when determining clearance between the 50 40 Care must be taken when determining clearance between the 40 resistor body and the P.C.B. or other components. Resistance 30 resistor body and the P.C.B. or other components. Resistance 30 20 is measured 6mm from body. 20 10 is measured 6mm from body. 10 0 20 40 60 80 100 120 140 160 180 200 220 240 260 2800 20 40 60 80 100 120 140 160 180 200 220 240 260 280 Temp Temp 10 Packaging 10 Packaging The standard method of packaging is taped in ammo packs. The standard method of packaging is taped in ammo packs. Can be provided on reels by request. Can be provided on reels by request. These products are also available in a range of lead forming options. These products are also available in a range of lead forming options. f f 1 2 f f 1 2 In particular, it is available in ZI-form SMD format packed in blister tape In particular, it is available in ZI-form SMD format packed in blister tape 6 63 6 see