Resistors Compact Flameproof Power Compact Flameproof Power Welwyn Components Wirewound Resistors Wirewound Resistors WP-S Series WP-S Series s Small size for power rating s Enhanced pulse handling capability Small size for power rating s Flameproof protection Enhan ced pulse handling capability Flameproof protection s SMD Z-form available Surface mount ZI-form option s RoHS compliant with Pb-free terminations RoHS compliant with Pb-free terminations All Pb-free parts comply with EU Directive 2011/65/EU (RoHS2) Electrical Data WP1S WP2S WP25S WP3S WP4S WP5S Power rating at 25 C watts 1 2 2.5 3 4 5 5s overload rating at 25C watts 5 10 12.5 15 20 25 Short pulse performance See Pulse Performance graphs Resistance range ohms R068 to 430R R05 to 900R R05 to 900R R01 to 2K2 R01 to 10K R015 to 6K8 Limiting element voltage volts 50 50 75 100 100 150 TCR ppm/C <1R: 350 1R: 200 Isolation Voltage volts 250 350 500 Resistance Tolerance % <20R: 5 20R: 1, 2, 5 <R10: 5 <20R: 5 R10: 1, 2, 5 20R: 1, 2, 5 Standard Values E24 preferred Thermal Impedance C/watt 140 110 90 82 62 54 Ambient temperature range C -55 to +155 Physical Data Dimensions (mm) & Weight (g) D Type L max D max f min d nom PCB Min Wt. mount bend nom centres radius WP1S 6.2 2.8 21.20 0.6 10.20 0.6 0.22 WP2S 9.0 3.6 19.80 12.70 0.50 WP25S 12.5 4.5 17.80 18.40 0.50 1.2 0.8 WP3S 14.5 5.2 24.5(Note 1) 5 20.30 1.10 L f d WP4S 13 5.6 22.7(Note 2) 5 18.90 1.00 (Note 3) WP5S 16.5 7.0 23.55 22.86 1.75 Note 1: 5.4 for values 0R1 Note 2: 5.8 for values 0R1 Note 3: 7.2 for values 0R1 Construction A high purity ceramic substrate is assembled with interference fit end caps to which are welded the terminations. The resistive element is wound on the substrate and welded to the caps. Flameproof silicone cement coating is applied prior to marking with indelible ink. The components are then leadformed if required and packed. GeneralGeneral Not Notee BI Technologies IRC Welwyn Welwyn Components reserves the right to make changes in product specification without notice or liability. TT Electronics reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyns own data and is considered accurate at time of going to print. A subsidiary of All information is subject to TT Electronics own data and is considered accurate at time of going to print. Compact Flameproof Power Compact Flameproof Power Compact Flameproof Power Compact Flameproof Power Wirewound Resistors Compact Flameproof Power Wirewound Resistors Wirewound Resistors Wirewound Resistors Welwyn Components WP-S Series Wirewound Resistors Welwyn Components WP-S Series Welwyn Components WP-S Series WP-S Series Welwyn Components WP-S Series Terminations Terminations Terminations Material: Hot tin dipped copper wire Terminations Material: Hot tin dipped copper wire Strength: The terminations meet the requirements of IEC 68.2.21 Material: Hot tin dipped copper wire Material: Hot tin dipped copper wire Strength: The terminations meet the requirements of IEC 68.2.21 Solderability: The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 Strength: The terminations meet the requirements of IEC 68.2.21 Strength: The terminations meet the requirements of IEC 68.2.21 Solderability: The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 Solderability: The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 Solderability: The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 Marking Marking Marking Marking WP1S, WP2S, WP25S and WP3S resistors R10 and above are marked with four or five colour bands in conformance with IEC62. WP1S, WP2S, WP25S and WP3S resistors R10 and above are marked with four or five colour bands in conformance with IEC62. Values below R10 are marked with three bands (two digits indicating value in milliohms, and tolerance) there is no multiplier WP1S, WP2S, WP25S and WP3S resistors R10 and above are marked with four or five colour bands in conformance with IEC62. WP1S, WP2S, WP25S and WP3S resistors R10 and above are marked with four or five colour bands in conformance with IEC62. Values below R10 are marked with three bands (two digits indicating value in milliohms, and tolerance) there is no multiplier band. WP4S and WP5S resistors are legend marked with type reference, resistance value and tolerance. Values below R10 are marked with three bands (two digits indicating value in milliohms, and tolerance) there is no multiplier Values below R10 are marked with three bands (two digits indicating value in milliohms, and tolerance) there is no multiplier band. WP4S and WP5S resistors are legend marked with type reference, resistance value and tolerance. band. band. WP4S and WP5SWP4S and WP5S resistors resistors a raer elegend legend marked marked with with type type refe reference,rence, resistance resistance value value and and tolerance. tolerance. Solvent Resistance Solvent Resistance Solvent Resistance Solvent Resistance The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. Flammability Flammability Flammability Flammability The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload. The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload. The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload. The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload. Performance Data Performance Data Performance Data Performance Data Maximum Typical Change Maximum Typical Change Maximum Typical Change Load at rated power: 1000hrs 25C R% 5 +0.001 3 Maximum Typical Change Load at rated power: 1000hrs 25C R% 5 +0.001 3 Load at rated power: 1000hrs 25C R% 5 +0.001 3 Dry heat: 1000hrs 200C R% 5 +0.001 3 Load at rated power: 1000hrs 25C R% 5 +0.001 3 Dry heat: 1000hrs 200C R% 5 +0.001 3 Dry heat: 1000hrs 200C R% 5 +0.001 3 Short term overload (5 x Pr for 5s) R% 5 +0.001 1 Dry heat: 1000hrs 200C R% 5 +0.001 3 Short term overload (5 x Pr for 5s) R% 5 +0.001 1 Short term overload (5 x Pr for 5s) R% 5 +0.001 1 Derating from rated power 25C Zero at 280C Short term overload (5 x Pr for 5s) R% 5 +0.001 1 Derating from rated power 25C Zero at 280C Derating from rated power 25C Zero at 280C Climatic R% 5 +0.001 2 Derating from rated power 25C Zero at 280C Climatic R% 5 +0.001 2 Climatic R% 5 +0.001 2 ClimaticClimatic categorycategory 55/200/5655/200/56 Climatic R% 5 +0.001 2 Climatic category 55/200/56 TRCTRC && VVibrationibration RR%% 55 +0.001+0.001 11 Climatic category 55/200/56 TRC & Vibration R% 5 +0.001 1 Robustness & solder heat R% 5 +0.001 1 Robustness & solder heat R% 5 +0.001 1 TRC & Vibration R% 5 +0.001 1 Robustness & solder heat R% 5 +0.001 1 Long term damp heat (56 days) R% 5 +0.001 1 Long term damp heat (56 days) R% 5 +0.001 1 Robustness & solder heat R% 5 +0.001 1 Long term damp heat (56 days) R% 5 +0.001 1 Long term damp heat (56 days) R% 5 +0.001 1 Pulse Performance Pulse Performance Pulse Performance Pulse Performance The pulse energy capacity limits in the graph below relate to pulses below 100ms duration, low mean power dissipation and at The pulse energy capacity limits in the graph below relate to pulses below 100ms duration, low mean power dissipation and at 25C. The pulse energy capacity limits in the graph below relate to pulses below 100ms duration, low mean power dissipation and at 25C. The pulse energy capacity limits in the graph below relate to pulses below 100ms duration, low mean power dissipation and at WP-S Short Pulse Energy Capacity 25C. WP-S Short Pulse Energy Capacity 25C. WP-S Short Pulse Energy Capacity 100 WP-S Short Pulse Energy Capacity 100 100 100 10 10 10 10 WP5S WP4S WP5S 1 WP4S WP5S WP3S WP5S WP25S 1 WP4S WP4S WP3S 1 WP2S WP25S 1 WP3S WP1S WP25S WP3S WP2S WP25S 0.1 WP2S WP1S WP2S 10000 0.1 1 10 100 1000 0.1 WP1S WP1S 0.1 Value (ohms) 10000 0.1 0.1 1 10 100 1000 10000 0.1 1 10 100 1000 10000 0.1 1 10 100 1000 Value (ohms) Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK GenerTelephone:al Not +44e (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info welwyn-tt.comValue (ohms) Website: www.welwyn-tt.com 08.10 Value (ohms) BI Technologies IRC Welwyn TT Electronics reserves the right to make changes in product specification without notice or liability. Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK All information is subject to TT Electronics own data and is considered accurate at time of going to print. 08.10 Telephone: +44 (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info welwyn-tt.com Website: www.welwyn-tt.com Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK