Aluminium Housed Wirewound Resistors Aluminium Housed Wirewound Resistors WH Series · High power dissipation up to 300W Series construction ·WH All welded ·• Suitable for severe environments High power dissipation up to 300W ·• Designed forconstruction excellent thermal conductivity to heatsink All welded ·• Spade terminal option Suitable for severe environments ·• RoHS compliant Designed for excellent thermal conductivity to heatsink • • Spade terminal option RoHS compliant Electrical Data Power rating at 25°C Resistance range watts ohms TCR (-55° to 200°C) ppm/°C Resistance tolerance Low value limits Isolation voltage WH5 10 0R01 to 10K WH10 15 0R01 to 20K <10R: ±75 % ohms volts WH25 25 2 0R01 to 44K ≥10R to <100R: ±50 TCR (-55° to 200°C) Resistance tolerance Low value limits Isolation voltage 1R at 1% 1500 0R5 at 2% 1500 AA 10 0R05 to 3K4 ppm/°C % ohms volts Notes On standard heatsink ≥100R: ±25 1(F), 2(G), 5(J) and 10(K) 0R05 at 5% 3000 Note 1: For load at full rating mount on aluminium heatsink 30.5 cm x 30.5 cm x 1.5 mm CECC 40203-006 Requirements * watts Power rating at 25°C Resistance range ohms WH50 50 1, 2 0R015 to 120K BA 15 0R05 to 15K WH50 0R015 at 10% DC or AC peak Note 2: WH25T & WH50T are additionally rated at 15A CA 25 0R05 to 33K ≥5R to ≤10R: ± 100 1000 0R01 at 10% 3000 DA 40 0R05 to 82K Notes On standard heatsink >10R: ±50 1(F), 2(G), and 5(J) 1R at 1% 0R5 at 2% 0R05 at 5% 1000 2000 2000 DC or AC peak * This table indicates the CECC specification requirements which are met or exceeded by the corresponding WH series products. Limiting element voltage Standard values Thermal impedance volts 150 °C/watt 16.0 Ambient temperature range °C Power rating at 25°C Resistance range watts ohms TCR (-55° to 200°C) ppm/°C Resistance tolerance Low value limits Isolation voltage Limiting element voltage Standard values Thermal impedance % ohms volts volts °C/watt Ambient temperature range °C 250 500 E24 preferred range 10.0 6.0 1250 3.5 DC or AC rms Other values to order On standard heatsink -55 to 200 WH100 100 0R01 to 70K WH200 200 0R01 to 50K WH300 300 0R01 to 68K Notes On standard heatsink ≤1K0: ±100 >1K0: ±25 Standard 5(J) and 10(K). also available : 1(F) and 2(G) Typically ≥0R05: ±5% ≤0R047: ±10% 6360 7070 7070 1900 1900 2500 E24 preferred range 1 0.7 0.6 DC or AC peak DC or AC rms Other values to order On standard heatsink -55 to 200 General Note General Note Components reserves right to make changes in without productnotice specification TTWelwyn electronics reserves the right to makethe changes in product specification or liability. without notice or liability. information is subject to Welwyn’s data and is accurate considered accurate time of print. AllAll information is subject to TT electronics’ ownown datatest and is considered at time of going at to print. Welwyn Components Limited www.bitechnologies.com www.irctt.com www.welwyn-tt.com Electronics ©Welwyn TT electronics plcPark, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 822181 Fax: 01670 829465 Web: www.welwyn-tt.com 07. 12 Aluminium Housed Aluminium Housed Wirewound Resistors Wirewound Resistors WH Series Physical Data Dimensions (mm) & Weight (g) WH5, 10, 25 & 50 A Type Max WH5 30 WH10 36.5 15.9 14.3 1.9 21 11 2.4 21.0 5.2 WH25 51 19.8 18.3 2.8 28 15 3.3 29.0 7.2 WH50 72.5 21.4 39.7 2.8 30 16 3.3 51.0 7.9 2.6 1 2 WH100, 200 & 300 A Max 47.5 WH100 B C E F G H L M N Dt Wt. ±0.3 ±0.3 Min Max Max 12.4 11.3 1.9 17 9 Dia ±0.2 Max ±0.5 Max Min Nom 2.4 17.0 4.3 1.8 2.5 3.6 2.2 2.9 5.6 2.6 4.3 13 5.1 29 B Max 88 C Max 24.1 D Max 27.3 E Max 65.2 F ±0.3 35 G ±0.3 37 H Max 11.8 J Max 15.4 K Max 3.7 L 3 Nom 4.4 M Max - Dt Min 7.0 Wt. Nom 115 10.4 5.5 5.1 103.4 15 475 12.4 5.5 6.6 141.4 15 700 WH200 72.5 145.7 41.8 45.5 89.7 70 57.2 20.5 WH300 72.5 184.4 41.8 45.5 127.7 104 59 20.5 Note 1: Amax for WH25T is 71.3 WH5, 10, 25 & 50 Note 2: Amax for WH50T is 95.5 Note 3: WH100: ±0.25, WH200 & 300: ±0.45 WH100 WH200 & 300 Spade terminal on WH25T & WH50T Nominal dims in mm Construction Cap and lead assemblies are fitted to a high purity ceramic substrate. The resistive element is wound onto the substrate and welded to the caps. The wound rod is then moulded and fitted into aluminium housing to give optimum stability and reliability. End face tracking distance = Dt Marking The resistors are legend marked with type reference, resistance value and tolerance which will withstand all accepted industrial cleaning fluids. Values are marked in accordance with IEC 62 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 test data and is considered accurate at time of print. General Note Welwyn Components Limited TT electronics reserves the right Bedlington, to make changes in product specification notice or liability. Welwyn Electronics Park, Northumberland, NE22without 7AA, England. Tel: 01670 All information is subject to TT electronics’ own data and is considered accurate at time of going to print. 822181 Fax: 01670 829465 Web: www.welwyn-tt.com www.bitechnologies.com www.irctt.com www.welwyn-tt.com © TT electronics plc 07. 12 Aluminium Housed Aluminium Housed Wirewound Resistors Wirewound Resistors WH Series Terminations WH5-100 Material Strength WH25T & 50T 6.35mm (¼“) spade terminal Pb-free solder dipped, copper clad steel The terminations meet the requirements of IEC 68.2.21 The terminations meet the requirements of IEC 115-1, clause 4.17.3.2 Solderability Performance Data Load at commercial rating: 1000hrs at 25°C Load at CECC rating: 1000hrs at 25°C Dry heat: 1000hrs at 200°C Derating from 25°C Short-term overload Climatic sequence Climatic category Long-term damp heat Temperature rapid change Resistance to solder heat Vibration and bump Noise (in decade of frequency) Insulation resistance Pulse and overload performance ∆R% ∆R% ∆R% ∆R% ∆R% ∆R% ∆R% ∆R% ∆R% µV/V ohms WH200 & 300 Material M6 threaded steel terminal with a set of four nuts and washers Strength Termination robustness 50N max Tightening torque 5Nm max WH5, 10, 25 & 50 WH100, 200 & 300 CECC 40203-006 Actual Maximum Requirements Maximum Typical 1 1 0.4 2 1 1 0.4 N/A 1 1 0.4 2 Zero at 200°C, see derating graph 1 1 0.2 1 1 0.4 55/200/56 1 0.5 0.2 0.25 0.25 0.1 0.25 0.25 0.25 0.05 WH100: 0.5 0.25 0.25 0.025 Not specified 0 0 0 1G min 10G min Not specified See graphs Note: A 0.05 ohm addition is to be added to the performance of all resistors < 10 ohms. 10000 Pulse and Overload Performance 10 WH25-300 WH5&10 1000 Energy (joules) Multiple of Rated Power For short durations of ≤0.1s the energy graph should be used. For longer durations the overload graph applies. 100 WH300 WH200 WH100 10 WH50 WH25 1 WH5-50 1 0.1 1 10 Overload Duration (s) WH10 WH100-300 100 1000 WH5 0.1 0.01 0.1 1 10 100 1000 10000 100000 Value (ohms) Application Notes After soldering, care should be taken to ensure that there are no flux residues on the end faces of the moulding compound, otherwise insulation resistance will be reduced. The minimum surface tracking distances from termination to casing are shown in the Physical Data tables as dimension Dt. It is recommended that the resistor base should be coated thinly with heatsink compound before mounting to obtain the stated operating characteristics. The heatsink compound increases thermal conductivity to the heatsink. 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 test data and is considered accurate at time of print. General Note Welwyn Components Limited TT electronics reserves the right to make changes in product specification without notice or liability. Welwyn Electronics Park, Bedlington, Northumberland, NE22 7AA, England. Tel: 01670 All information is subject to TT electronics’ own data and is considered accurate at time of going to print. 822181 Fax: 01670 829465 Web: www.welwyn-tt.com www.bitechnologies.com www.irctt.com www.welwyn-tt.com © TT electronics plc 07. 12 Aluminium Housed Aluminium Housed Wirewound Resistors Wirewound Resistors WH Series The standard aluminium heatsinks are defined in the table below. If smaller heatsinks are used then derating should 2 be applied as indicated in the graph below. If no heatsink is employed, use the ratings for 1cm . Type (CECC) Thickness (mm) WH5 (AA) 1 WH10 (BA) 1 WH25 (CA) 1 WH50 (DA) 1 WH50 @ 50W 1.5 WH100 3 WH200 3 WH300 3 Area (cm²) 410 410 544 544 930 1000 3800 5800 Derating for ambient temperature Proportion of Pr (%) 1 20 1 00 80 Derating for reduced heatsink dimensions 1000 WH300 25°C WH300 70°C WH200 25°C WH200 70°C Ma xim um Dis sipa tion (W) Reference heatsink dimensions 100 WH100 25°C WH100 70°C WH50 25°C DA 25°C DA 70°C WH25/CA 25°C WH25/CA 70°C WH10/BA 25°C WH10/BA 70°C WH5/AA 25°C 10 WH5/AA 70°C 60 40 20 0 0 10 0 1 20 0 1 10 A m b ie n t T e m p e ra tu r e (°C ) 100 1000 10000 2 Heatsink Surface Area (cm ) Packaging WH5, 10, 25, 50 &100 resistors are packed in plastic bags and boxed. WH200 & 300 are individually boxed. Ordering Procedure Example: WH25 with spade terminals at 100 ohms with a 5% tolerance: WH25T–100RJI Type Termination Standard Spade terminal T Value (use IEC62 code) Tolerance (use IEC62 code) F G 1% 2% J K 5% 10% Packing I WH5, 10, 25, 50 WH100, 200, 300 Bulk 10/box 1/box Standard The following options apply to WH5, 10, 25 & 50 only: For CECC released product state on order the CECC number and style. Example: WH25-3K3JI CECC40203-006 CA For SnPb finish instead of Pb-free replace the packing suffix with PB. Example: WH25-3K3JPB General Note TT electronics reserves the right to make changes in product specification without notice or liability. All information is subject to TT electronics’ own data and is considered accurate at time of going to print. www.bitechnologies.com www.irctt.com www.welwyn-tt.com © TT electronics plc 07. 12