Ultra Precision Wire-Wound Resistors Type UPW Series Characteristics Electrical Type UPW Series The resistive element is wire wound onto a moulded high temperature plastic bobbin with a central former. UPW15 0.125 Rated Power @ 125°C (W) Derate to zero at 145°C Resistance Range (Ohms) Min Max Tolerance (%) Code Letter Limiting Element Voltage (V) Temperature Coefficient (ppm/°C) Typ. Max. Operating Temperature Range (°C) Long Term Stability (Load) UPW25 0.25 R10 300K UPW50 0.5 R10 R10 1M0 1M0 0.005 0.01 0.02 0.05 0.1 0.2 0.5 1 E L P W B A D F 300 150 ± 3 (0°C to +85°C) ± 5 (-55°C to +125°C) ± 1 available on request -55 to +145 < 50 ppm @ 10,000 hrs < 100ppm @ 26,000 hrs < 0.2 µ V /°C 150 The direction of winding is reversed part way through the winding, giving UPW30 0.3 Thermal EMF R10 2M0 400 very low values of inductance. These Neohm resistors use bobbin assemblies with flattened lead ends, providing high resistance to pull, vibration and torsional forces during Dimensions Style A Style B handling, assembly and life. Key Features ■ Custom weld tabs and copper weld leads ensure a good mechanical and electrical connection between the element and the lead wires. Protection is given to the windings by means of a layer of silicone RTV rubber. This allows movement of the windings during temperature cycling due to loads and to varying ambient temperatures. Outer protection is given by means of a hot transfer moulded epoxy compound which ensures an airtight coating with no trapped air. Superior quality wire-wound resistors with very low selection tolerances and temperature coefficients down to 1 ppm. 3 case sizes are available. T/C, ratio and pair matching is available and customer specifications are welcome. These components exhibit high stability under load and severe environmental conditions. Type Style L ± 0.4 D ± 0.4 W ± 0.5 s ± 0.2 d nom UPW15 A 6.35 3.18 - - 0.64 UPW25 A 9.53 4.75 - - 0.64 UPW30 B 7.62 7.62 3.18 3.81 0.64 UPW50 A 12.7 6.35 - - 0.81 Derating Curve 100 1%, 0.5%, 0.2%, 0.1% 80 Percent Rated Power ■ 0.05% 60 0.02% 0.01% 40 20 0.005% 0 40 60 80 100 120 140 160 Ambient Temperature (°C) UPW Series resistors must be derated for tolerances below 0.1%. Use the graph to select tolerance versus operating temperature to determine the percentage rated power for operation. No derating is required for operation below 20 °C. Mounting The resistors are suitable for processing on automatic insertion equipment and cutting and bending machines. Literature No. 1773299 Issued: 04-05 Dimensions are shown for reference purposes only. Dimensions are in millimetres unless otherwise specified. Specifications subject to change. www.tycoelectronics.com passives.tycoelectronics.com Ultra Precision Wire-Wound Resistors Type UPW Series Marking The resistors are marked with the following information:- Manufacturer's name, type number, value and tolerance, four figure date code. Packaging UPW Series resistors are packed loose in boxes. Performance Characteristics The evaluation of the performance characteristics is carried out with reference to IEC specifications QC 400 000 and QC 400 100. TEST REF Long Term Tests ±(0.25% + 0.05 ohm) 4.23 Climatic sequence 4.24 Damp heat, steady state 4.25.1 Endurance at 70 °C 4.25.3 Endurance at 145 °C TEST REF Short Term Tests ±(0.1% + 0.01 ohm) 4.13 Overload 4.16 Robustness of terminations 4.18 Resistance to soldering heat 4.19 Rapid change of temperature 4.22 Vibration All resistance values are measured at a distance of 9.53mm (0.375 inch) from the end cap. How to Order Orders for these components should include the following information:Type, tolerance code letter and value e.g. UPW30 L 1K15 Literature No. 1773299 Issued: 04-05 Dimensions are shown for reference purposes only. Dimensions are in millimetres unless otherwise specified. Specifications subject to change. www.tycoelectronics.com passives.tycoelectronics.com