OAR_D.qxd 8/9/04 4:15 PM Page 1 Open Air Sense Resistors Welwyn Components OAR Series * * * * 1, 3 and 5 watts 1% or 5% tolerance Resistance wire TCR 20 ppm/C Resistance values down to 0R005 ohms Electrical Data OAR-1 OAR-3 OAR-5 Power rating at 85C watts 1 3 5 Resistance range ohms 0R005* to 0.10 0R005 to 0.10 0R005 to 0.05 * Contact factory for values below 0R005 ohms Physical Data Dimensions (mm) Type A B C E F OAR-1 11.43 +1.020/-0.508 5.08 2.54 3.18 0.762 1.65 +0.254/-0.127 1.02 0.051 OAR-3 15.24 +1.020/-0.50 25.4 max. 3.18 0.762 1.65 +0.254/0.127 1.02 0.051 OAR-5 20.32 +1.020/-0.50 25.4 max. 3.18 0.762 1.65 +0.254/-0.127 1.02 0.051 On lower ranges stand-off may be eliminated B NOTE: Contact factory for: 1. Variations of `A' dimension 2. Different lead diameter C A F Test Point (Kelvin connection) E 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. A subsidiary of TT electronics plc (c) 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 * 08.04 101 OAR_D.qxd 8/9/04 4:15 PM Page 2 Open Air Sense Resistors Welwyn Components OAR Series Height Standards All Resistances are in ohms. All Tolerances are 2.54. Dimensions (mm) OAR-1 Resistance 0.005 - 0.100 Height 5.080 OAR-3 Resistance 0.005 0.010 0.015 0.020 0.025 0.030 0.040 0.050 0.070 0.080 0.10 Height 16.002 16.510 16.510 17.018 22.098 22.860 16.002 18.288 22.860 21.590 22.860 OAR-5 Resistance 0.005 0.010 0.015 0.020 0.025 Height 15.240 19.304 19.304 22.860 22.860 Performance Data Maximum change Load life: 1000 hrs at 25C R% 1 Moisture No Load 100 hrs R% 1 Temperature Cycle at -40C & +125C (1000 cyc): R% 1 Features * Welded Construction * Flameproof * Inductance less than 10 nanohenries * Solderable copper leads Applications * Current Sensing * Feedback * Low inductance * Surge and pulse Ordering Procedure Example: OAR3 at 10 milliohms and 5% tolerance in bulk pack OAR3- R01JI Type Value (use IEC62 code) Tolerance (use IEC62 code) F J 1% 5% Packing I Bulk Standard (c) 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 102 Issue D * 08.04