Type UT and UB Silicone Coated Power Resistors RIEDON Resistances from 0.005 to 260K Ohms Power Rating 0.1 to 18 Watts Resistance Tolerances to ± 0.01% Low TCR: ± 20 ppm/°C Standard MIL-R-26 / MIL-R-39007 Power Ratings Temperature Range: -55°C to +350°C ( V Rating ) Non-Inductive Windings Available Riedon offers two versions of these wirewound power resistors. The UT Series has excellent performance and reliability in a moderate package size. The UB Series provides higher power ratings in the same size, yet meets the performance, environmental, and life stability requirements of the UT package. SPECIFICATIONS Type Wattage Rating ( Watts ) U V Maximum Resistance ( Ohms ) Dimensions Length Diameter A ±0.062 B ±0.031 Lead Dia. Max. Working MIL-R-26 / AWG * Voltage MIL-R-39007 C ±0.002 ( Volts ) UT-1 0.1 0.25 500 0.150 0.078 25 8.5 UT-1/2A 0.4 0.5 2.5K 0.250 0.078 24 / 22 20 UT-1/2 0.75 0.9 7.5K 0.330 0.078 24 / 22 29 UT-1A 1.0 1.5 10K 0.406 0.094 24 / 22 52 UT-2 1.5 2.0 12.5K 0.350 0.156 22 / 20 60 UT-2A 2.5 3.0 22K 0.500 0.187 20 130 RW-69 UT-2B 3.0 3.75 22K 0.560 0.187 20 140 RW-79 / RWR-89 UT-2C 3.0 4.0 40K 0.500 0.250 20 / 18 138 UT-2D 3.0 3.5 30K 0.500 0.187 20 140 UT-2E 3.0 3.5 30K 0.500 0.200 20 140 UT-3 4.0 5.5 45K 0.625 0.250 20 / 18 210 UT-5 5.0 6.5 91K 0.875 0.312 18 360 UT-5A 5.0 6.5 65K 0.970 0.203 20 / 18 390 UT-6 5.0 6.5 95K 1.000 0.312 18 504 UT-7A 7.0 9.0 150K 1.375 0.375 18 650 UT-7B 7.0 9.0 100K 1.400 0.312 18 590 UT-7C 7.0 9.0 154K 1.220 0.312 18 620 UT-10 10.0 13.0 260K 1.780 0.375 18 850 RW-70 RW-74 / RWR-74 RW-67 RW-78 / RWR-78 * Lead Diameter: 18 AWG = 0.040, 20 AWG = 0.032, 22 AWG = 0.025, 24 AWG = 0.020, 25 AWG = 0.018 Riedon Inc. REV 3/03 300 Cypress Avenue Alhambra CA 91801 www.riedon.com (626) 284-9901 Fax: (626) 284-1704 Type UT and UB Silicone Coated Power Resistors RIEDON SPECIFICATIONS ( Continued ) Power Derating Curve Charateristic Maximum Hotspot Temp. Temperature Range U +250°C -55°C to +250°C V +350°C -55°C to +350°C Wattage Rating ( Watts ) U V Type Maximum Resistance ( Ohms ) Power Level % Power Ratings and Temperature Range: UT and UB Series have two power ratings, depending on operating temperature and stability requirements. Dimensions Length Diameter A ±0.062 B ±0.031 120 100 80 60 40 20 0 CH AR CH AR 0 V U 50 100 150 200 250 300 350 Ambient Temperature °C Lead Dia. Max. Working MIL-R-26 / AWG * Voltage MIL-R-39007 C ±0.002 ( Volts ) UB-1 1.0 1.5 3.4K 0.250 0.085 24 / 22 33 RW-81 / RWR-81 UB-2 1.5 2.0 7.5K 0.312 0.078 24 / 22 42 RWR-82 UB-3 2.0 3.0 10K 0.406 0.094 24 / 22 80 RW-80 / RWR-80 UB-5 4.0 5.0 25K 0.562 0.188 20 162 UB-5C 5.0 7.0 32K 0.500 0.218 18 194 UB-6 6.0 8.0 50K 0.625 0..250 18 258 UB-10 7.0 10.0 95K 0.875 0.312 18 425 UB-12 10.0 12.0 150K 1.200 0.312 18 607 UB-15 15 18 260K 1.780 0.375 18 1050 RW-84 * Lead Diameter: 18 AWG = 0.040, 20 AWG = 0.032, 22 AWG = 0.025, 24 AWG = 0.020, 25 AWG = 0.018 Tolerances Temperature Coefficient - Dielectric Strength - ± 0.01% to ± 10% ( 1% Standard ) 1 to 10W, ±50ppm/°C >10W, ± 20ppm/°C <1W, ( Call factory ) 500 VAC: UT-1, 1/2A, 1/2, 1A UB-1, 2, 3 1000 VAC: All others ConstructionControlled low tension windings on centerless ground ceramic cores. All welded terminations. Special high-temperature trivalent inorganic silicone material that will not support combustion and will withstand degreasing solvents and aqueous cleaning. Leads are tinned copper or copperweld and are solderable and weldable. Ordering information: Part Number - Resistance - Tolerance - TCR Example: UT-5 - 25K - 0.1 - 20 Note for non-indutive windings: Insert the Letter N ( example: UNT-3 ) Divide maximum resistance by two, Multiply working voltage by 0.707. Riedon Inc. REV 3/03 300 Cypress Avenue Alhambra CA 91801 www.riedon.com 1.00 Min A fC fB Environmental Performance ( MIL-STD 202 ) Condition Dielectric Load Life Storage Moisture Resistance Thermal Shock 5X Overload for 5 sec. Shock Vibration (626) 284-9901 DR ± 0.2% + 0.05W ± 0.5% + 0.05W ± 0.2% + 0.05W ± 0.2% + 0.05W ± 0.2% + 0.05W ± 0.2% + 0.05W ± 0.1% + 0.05W ± 0.1% + 0.05W Fax: (626) 284-1704