RPH 100 Vishay Sfernice Power Resistor for Mounting onto a Heatsink Thick Film Technology FEATURES • High power rating • Low thermal radiation of the case RoHS COMPLIANT • Wide ohmic value range • Easy mounting • High overload capabilities • Reduced size and weight This new style has been developed as an extension to RCH range. Through the use of thick film technology, a non-inductive solution for power resistors is available which are rated up to 100 W at + 25 °C. The terminations position prevents any risk of an electrical arc to the heatsink. This resistor series can replace and offer advantages to standard wirewound devices. DIMENSIONS in millimeters RPH 100 V Connections 42,4 4 16,6 18,6 21,6 65,5 35 ø 4,2 26 37 46,7 ø 4,2 MECHANICAL SPECIFICATIONS Mechanical Protection Substrate Resistive Element End Connections Tightening Torque Connections Tightening Torque Heatsink Weight Insulated case Alumina on metallic base of nickel coated aluminum Cermet V connections: screws M4 x 6 1 Nm 3 Nm 60 g ELECTRICAL SPECIFICATIONS 0.092 Ω to 1 MΩ E24 series ± 1 % to ± 10 % Resistance Range Tolerances Power Rating: Continuous Momentary Temperature Coefficient Standard ENVIRONMENTAL SPECIFICATIONS Thermal Resistance Temperature Range Climatic Category www.vishay.com 24 RTH (j-c) 0.55 °C/W - 55 °C + 125 °C 55/125/56 Limiting Element Voltage Dielectric Strength MIL STD 202 Insulation Resistance Inductance For technical questions, contact [email protected] 100 W at 25 °C chassis mounted 0.45°C/W 10 W at 25 °C Free air 400 W at 25 °C for 5 seconds ± 300 ppm/°C < 1 Ω ± 150 ppm/°C > 1 Ω 1900 VRMS 5 kVRMS 1minute 10 mA Max > 106 MΩ < 0.1 µH Document Number: 50046 Revision 30-May-06 RPH 100 Power Resistor for Mounting onto a Heatsink Thick Film Technology Vishay Sfernice PERFORMANCE TESTS Short Time Overload CONDITIONS NF EN 140000 CEI 115_1 4 Pn/5 seconds NF EN 140000 CEI 68214 Test Na 5 cycles - 55 °C + 125 °C NF EN 140000 Pn at 25 °C 1000 hours MIL STD 202 Method 103 B Test D 56 days 95 % R.H. Rapid Temperature Change Load Life (chassis mounted 0.45°C/W) Humidity (steady state) TYPICAL DRIFTS < ± (0.25 % + 0.05 Ω) < ± (0.25 % + 0.05 Ω) < ± (0.5 % + 0.05 Ω) < ± (0.5 % + 0.05 Ω) RESISTANCE VALUE IN RELATION TO TOLERANCE AND TCR Ohmic Value Standard Tolerance Standard T.C.R. Tolerances On Request >1Ω ±5% ± 150 ppm/°C < 1Ω ±5% ± 300 ppm/°C ± 1 % - ± 2 % - ± 10 % CHOICE OF THE HEATSINK The user must choose according to the working conditions of the component (power, room temperature). Maximum working temperature must not exceed 125 °C. The dissipated power is simply calculated by the following ratios: P= ΔT (1) [RTH(j-c) + RTH (c-a)] P: expressed in W ΔT: difference between maximum working temperature and room temperature. RTH: (j-c): thermal resistance value measured between resistive layer and outer side of the resistor. It is the thermal resistance of the component: 0.55 °C/W. RTH: (c-a): thermal resistance value measured between outer side of the resistor and room temperature. It is the thermal resistance of the heatsink itself (type, shape) and the quality of the fastening device. Example: RTH: (c-a) for RPH 100 power rating 80 W at ambient temperature + 40 °C. Thermal resistance RTH (j-c): 0.55 °C/W Considering equation (1) we have: ΔT ≤ 125 °C - 40 °C ≤ 85 °C 85 RTH (j-c) + RTH (c-a) = ΔT = =1.06 °C/W 80 P RTH (c-a) ≤ 1.06 °C/W - 0.55 °C/W ≤ 0.51 °C/W RECOMMENDATIONS FOR MOUNTING ONTO A HEATSINK Surfaces in contact must be carefully cleaned. The heatsink must have an acceptable flatness: from 0.05 mm to 0.1 mm/100 mm. Roughness of the heatsink must be around 6.3 µm. In order to improve thermal conductivity, surfaces in contact (alumina, heatsink) should be coated with a silicone grease (type SI 340 from Rhône-Poulenc or Dow 340 from Dow Corning). The fastening of the resistor to the heatsink is under pressure control of four screws (not supplied). Tightening torque: 3 Nm In order to improve the dissipation, either forced-air cooling or liquid cooling may be used. Do not forget to respect an insulation value between two resistors (dielectric strength in dry air 1 kV/mm). Document Number: 50046 Revision 30-May-06 For technical questions, contact [email protected] www.vishay.com 25 RPH 100 Vishay Sfernice Power Resistor for Mounting onto a Heatsink Thick Film Technology OVERLOADS In any case the applied voltage must be lower than 2 Un. U maxi < 2 Un < 3800 V Short time overload: 4 Pn/5 seconds Accidental overload: The values indicated on the graph below are applicable to resistors in air or mounted onto a heatsink. ENERGY CURVE ENERGY IN JOULES 1000 100 10 1 0.1 1.10-7 1.10-6 1.10-5 1.10-4 1.10-3 1.10-2 1.10-1 1 OVERLOAD DURATION IN SECONDS POWER RATING CHART For resistor mounted onto a heatsink with thermal resistance of 0.45 °C/W. 100 % RATED POWER 80 60 40 20 0 Packaging Box of 5 units 0 20 40 60 80 100 120 140 AMBIENT TEMPERATURE IN DEGREES CELSIUS MARKING Series, style, ohmic value (in Ω), tolerance (in %), manufacturing date, SFERNICE trade mark. ORDERING INFORMATION RPH MODEL 100 100K 5% STYLE RESISTANCE VALUE TOLERANCE Optional ±1% ±2 % ±5% ± 10 % V XXX CONNECTIONS CUSTOM DESIGN V: screw M4 B05 e PACKAGING LEAD (Pb)-FREE Options on request TCR, shape, etc. SAP PART NUMBERING GUIDELINES RPH 100 V 10002 J B MODEL STYLE CONNECTIONS OHMIC VALUE TOLERANCE PACKAGING www.vishay.com 26 For technical questions, contact [email protected] Document Number: 50046 Revision 30-May-06 Legal Disclaimer Notice Vishay Notice Specifications of the products displayed herein are subject to change without notice. Vishay Intertechnology, Inc., or anyone on its behalf, assumes no responsibility or liability for any errors or inaccuracies. Information contained herein is intended to provide a product description only. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this document. Except as provided in Vishay's terms and conditions of sale for such products, Vishay assumes no liability whatsoever, and disclaims any express or implied warranty, relating to sale and/or use of Vishay products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright, or other intellectual property right. The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications. Customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Vishay for any damages resulting from such improper use or sale. Document Number: 91000 Revision: 08-Apr-05 www.vishay.com 1