Semi-Precision Power Wirewound Resistor Welwyn Components AS Series • 0.25 to 10 watts • Tolerance down to ±0.5% • 0.1 ohm to 175K ohms • Resistance wire TCR ±20 ppm/°C Electrical Data Type AS-1/4 Equivalent MIL-R-26 Style RW81 AS-1/2 AS-1 RW70U Power Rating (watts) 125°C 25°C Commercial Range (ohms) Min. Max. Non-Inductive Range (ohms) Min. Max. Available Resistance (ohms) 0.5%, 1% 3%, 5% 0.5 1 0.1 1.0K * * 1-1K 0.1-1K 0.5 1 0.1 6.0K * * 1-6K 0.1-6K 0.1-7.5K 1 2 0.1 7.5K 0.1 3.8K 1-7.5K 1 2 .05 2K * * 1-2K .05-2K 2 3 0.1 20K 0.5 10K 1-20K 0.1-20K AS-2B 3 4 0.1 24K 0.5 12K 1-24K 0.1-24K AS-2C 2 3 0.1 18K 0.2 7.5K 1-18K 0.1-18K AS-3 3 5 0.1 30K 0.5 15K 1-30K 0.1-30K 5 7 0.1 60K 0.8 30K 1-60K 0.1-60K 7 9 0.1 90K 1.0 45K 1-90K 0.1-90K 10 14 0.1 175K 3.0 50K 1-175K 0.1-175K AS-1C AS-2 RW-69V/ RW79U AS-5 RW74U/ RW67U AS-7 AS-10 RW68V/ RW78U Inductance of AS-1/2 is less than 1µH at 1MHz. To order non-inductive types, add the prefix ‘N’. Example: NAS-1, NAS-2C, etc. * Typical inductance of AS-1C <5ohms is <1µH. Lower values available upon request. Physical Data Dimensions (mm) Type A ±0.81 B (max) C (max) D (Lead Diameter) AS-1/4 6.4 2.4 7.9 0.5 AS-1/2 7.9 2.4 9.5 AS-1 9.3 3.2 10.9 0.5 0.64 AS-1C 6.5 2.9 7.7 0.64 0.8 AS-2 12.2 6.3 15.2 0.8 AS-2B 13.7 5.6 16.6 0.8 AS-2C 11.0 4.0 15.1 0.8 AS-3 17.5 7.2 20.6 1.0 AS-5 22.2 8.8 24.9 1.0 AS-7 31.8 8.8 35.0 1.0 AS-10 46.0 9.8 49.2 1.0 1.50 min. (38.1) A D 0.5 B C Please note lead length dimension change on the following two items only: AS-2B 33.0mm (min) AS-2C 33.0mm (min) Note: • Coating and marking is resistant to normal freon degreasing. Consult factory for special requirements. • AS marking available in Alpha Numeric or Colourbanding identification available. * Leads are solder plated. AS-1C leads are copper. All others are 40% conductivity copper sheathed steel. General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyn’s own data and is considered accurate at time of going to print. © Welwyn Components Limited · Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: [email protected] · Website: www.welwyn-tt.com A subsidiary of TT electronics plc Issue D · 03.06 91 Semi-Precision Power Wirewound Resistor Welwyn Components AS Series Temperature Rise @ 25°C Power Derating 275 200 AS-2A, 2C 175 AS-3, AS-5 AS-3, 2 150 Hot Spot Temperature (C) Percent of 125C Power Rating AS-7, 10 250 AS-1/4, 1/2, 1, 1C AS-2C AS-5, 10 125 AS-2B 100 AS-7 75 200 AS-2B AS-2A, 2C 150 AS-1/2 100 AS-1/4 50 25 0 25 75 125 175 225 0 275 40 80 120 Temperature Rise @ 125°C 200 Selected Pulse-Handling Capability @ 125°C 275 14 AS-7, 10 AS-2A 12 AS-3, AS-5 AS-2B AS-2 AS-2A, 2C AS-1/2 200 AS-1/4 Energy (watts-second) 250 Hot Spot Temperature (°C) 160 Percent of 25C Power Rating Ambient Temperature (C) AS-3 AS-2 10 8 AS-2B 6 AS-2C 4 AS-1 150 125 0 2 40 80 120 160 0 0.1 200 AS-1/2 AS-1/4 Percent of 125°C Power Rating 0.2 0.5 1 2 Resistance (ohms) 5 10 Environmental Testing at 25°C Max ∆R Test Condition Load Life 1000 hours 1.0% Moisture Resistance 1.0% Temperature Cycle 0.5% Short Time Overload 0.5% Low Temperature Operation 0.5% Solder Heat 0.25% Shock 0.5% Vibration 0.5% Packaging Parts are supplied taped and reeled. Standard quantity per reel. Standard Quantities Per Package AS 1/4, 1/2, 1C 2,000 AS 1, 2, 2B, 2C 1,000 AS 3 1,000 AS 5, 7, 10 © Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: [email protected] · Website: www.welwyn-tt.com 92 500 Issue D · 03.06 Semi-Precision Power Wirewound Resistor Welwyn Components AS Series Ordering Procedure Specify type reference, value and tolerance as shown in this example of AS1/4 1K0 5%: Type AS1/4 1K0 J Resistance value (IEC62 code) Tolerance (IEC62 code) F 1% G 2% J 5% © Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: [email protected] · Website: www.welwyn-tt.com Issue D · 03.06