High Voltage Low Inductance Thick film Resistors Welwyn Components HVL Series • • • • • • Working voltage up to 48kV Low inductance Resistance up to 4G Low temperature coefficient of resistance Low voltage coefficient Sets of resistors with matched characteristics Electrical Data HVL 43 HVL 44 HVL 45 Power rating at 70°C watts 1.5 3.5 5.0 Resistance range ohms 1K to 1G 1K to 2G 1K to 4G volts 4K 14K 24K In air 8K 28K 48K In oil Limiting element voltage TCR (20°C to 70°C) ppm/°C Resistance tolerance % Values Thermal impedance °C/watt Notes 25, 50, 100 Values >1G: TCR is 250ppm/°C 1, 2, 5 Closer tolerances over restricted range E24 preferred values Any value to special order 31 Ambient temperature range 27 20 -55 to 155 Physical Data Dimensions (mm) and Weight (g) L max. D max. f min. d nom. PCB mounting centres HVL 43 25.4 8.0 30 0.8 31.8 1.2 3.1 HVL 44 50.8 8.0 30 0.8 57.2 1.2 5.6 HVL 45 84.2 8.0 30 0.8 87.2 1.2 5.6 Type Min. bend radius Wt. nom. d D L f Construction Marking A ruthenium oxide based resistive film is fired onto a high quality ceramic former. Cap and lead assemblies are force fitted to the former. The resistor is adjusted to value and the body is protected with a silicone coating. Type reference, resistance value, tolerance and date code are legend marked. The resistance value conforms to IEC 62. Terminations Material Solder coated copper wire. Strength The terminations meet the requirements of IEC 68.2.21. Solvent Resistance The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. Solderability The terminations meet the requirements of IEC 115-1, Clause 4.17.3.2. 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 © 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 B · 03.02 197 High Voltage Low Inductance Thick film Resistors Welwyn Components HVL Series Performance Data Maximum Typical Load at rated power: 1000 hours at 70°C ∆R% 1 0.3 Shelf life: 12 months at room temperature ∆R% 0.3 0.1 Noise (in a decade of frequency) µV/V 5 <2.5 Voltage coefficient of resistance ppm/volt 5 <1 Derating from rated power at 70°C Zero at 155°C Matched Sets Resistors in a set can be supplied for use as precision voltage dividers matched for tolerance and TCR down to 0.5% and 10ppm/°C. ENQUIRIES ARE WELCOMED FOR SPECIAL RESISTORS AND SETS Application Notes Mounting Packaging Due to the high voltage which can appear between the end cap and any adjacent metal part, resistors should be mounted at an adequate distance from other conductors. Resistors are supplied packed in boxes. For some high voltage applications it is required to immerse the components in oil or gas to reduce the effects of corona and surface tracking. The protective coating is suitable for these applications. Standard Quantities Per Box All Types 10 or 20 per box The axial termination should not be bent closer than twice the diameter of the terminal wire from the body of the resistor. When the resistors are required to be plotted, the preferred encapsulant is a silicone compound. For voltage dividers with a low resistance section below the minimum available value of 1k ohms, it is normal practice to use a Welwyn resistor, RC Series, obtainable down to 1ohm. © 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 198 Issue B · 03.02