PRODUCT BULLETIN WILLOW TECHNOLOGIES LTD. SHAWLANDS COURT, NEWCHAPEL ROAD LINGFIELD, SURREY, RH7 6BL, ENGLAND Tel. + 44 (0) 1342 835234 Fax. + 44 (0) 1342 834306 E-mail [email protected] Website http://www.willow.co.uk WW-SERIES FLAMEPROOF WIREWOUND RESISTORS 1 TO 10 WATT 0.1% THRU 10% TOLERANCE SILICONE COATED HIGH PURITY CERAMIC CORE STAINLESS STEEL END CAPS TINNED COPPER-CLAD STEEL LEADS WELDED CONSTRUCTION PACKAGED TAPE & REEL OR BULK AVAILABLE IN NON-INDUCTIVE STYLE MEETS REQUIREMENTS FOR MIL-R-26 1.375" Min. Specifications PRP Style U V WW1/2 .75 1.0 0.1 WW1 1.0 1.5 WW2 2.0 WW3 Wattage Voltage Resistance Range U V to 5.23K 32 44 0.1 to 5.0K 44 54 2.6 .02 to 7.2K 65 77 3.0 3.6 .01 to 9.5K 130 147 WW4 4.0 5.0 0.1 to 14.0K 210 250 WW5 5.0 6.5 .01 to 42.0K 360 410 WW7 7.0 8.0 0.1 to 63.0K 490 530 10.0 11.0 0.1 to 92.0K 632 700 WW10 L D Dimensional Correlation d Dimensions DIMENSIONS Inches PRP Style L D WW1/2 .266 ± .015 .095 ± .015 .025 * WW1 .400 ± .030 .100 ± .030 .025 * .460 ± .030 .175 ± .030 .032 Lead Dia. (d) in. mm WW2 .015 .020 .025 .030 .032 .060 .095 0.38 0.5 0.64 0.76 0.81 1.52 2.41 WW3 .490 ± .030 .210 ± .030 .032 WW4 .550 ± .030 .220 ± .030 .032 WW5 .910 ± .030 .295 ± .030 .032 WW7 1.250 ± .060 .295 ± .030 .032 WW10 1.750 ± .060 .295 ± .030 .032 .100 .175 .210 .220 .266 .295 .400 .460 .490 .550 .910 1.25 1.75 2.54 4.45 5.33 5.59 6.76 7.49 10.2 11.7 12.4 14.0 23.1 31.8 44.5 * ALSO AVAILABLE IN .020 Temperature TC20 = ±20PPM/°C, 10 ohm and above. TC50 = ±50PPM/°C, 1 ohm - 9.9 ohm. TC90 = ±90PPM/°C, below 1 ohm. How to Order Sample Part Number WW1 TC20 7.5K ±1% S S = Standard Options N = Non-Inductive Resistance Tolerance Resistance Value Temperature Coefficient Type DEDICATION TO EXCELLENCE Subject to change without notice Continued on reverse side ENVIRONMENTAL SPECIFICATIONS CHARACTERISTIC U ± .5% + .05 Ω ± .2% + .05 Ω ± .2% + .05 Ω ± .2% + .05 Ω ± .1% + .05 Ω ± .2% + .05 Ω ± .5% + .05 Ω ± .1% + .05 Ω ± .1% + .05 Ω ± .1% + .05 Ω LOAD LIFE MOISTURE RESISTANCE THERMAL SHOCK SHORT TIME OVERLOAD DIELECTRIC STRENGTH LOW TEMP. STORAGE HIGH TEMP. EXPOSURE TERMINAL STRENGTH SHOCK VIBRATION V ± 3.0% + .05 Ω ± .2% + .05 Ω ± .2% + .05 Ω ± .5% + .05 Ω ± .1% + .05 Ω ± .2% + .05 Ω ± .5% + .05 Ω ± .1% + .05 Ω ± .1% + .05 Ω ± .1% + .05 Ω Derating Curve 100 LOAD % 80 CHAR. V 60 CHAR. U 40 20 0 25 50 75 100 125 150 175 200 225 250 AMBIENT TEMP (°C) WW Series resistors have an operating temperature of -55°C to +350°C. They must be derated for use at high ambient temperatures as shown above. Resistors with characteristic V are available in 3%, 5% and 10% only. Subject to change without notice 275 300 325 350