Resistors Resistors UL Recognised UL Recognised Wirewound Resistors Wirewound Resistors ULW Series ULW Series UL1412 recognised fusible resistor * UL1412 recognised fusible resistor * Failsafe mains fusing at 120 / 240Vrms Failsafe mains fusing at 120 / 240Vrms Inrush and surge withstanding Inrush and surge withstanding UL94-V0 flamepr oof coating UL94-V0 flameproof coating Surface mount ZI-form option Surface mount ZI-form option * UL file number E234469. * UL file number E234469. All Pb-All Pb-frfreeee parts c parts comply omply with EU Dirwith EU Directivective e 2011/65/EU amended b2011/65/EU amended by y (EU) 2015/863 (R(EU) 2015/863 (RoHS3)oHS3) All Pb-free parts comply with EU Directive 2011/65/EU (RoHS2) Electrical Data ULW2 / ULWP2R ULW3 ULW4 ULW5 Power rating at 25C watts 2 3 4 5 5 second overload rating at 25C watts 10 15 20 25 Inrush / surge performance See Pulse Performance graphs Resistance range ohms 1R0 to 100R TCR ppm/C 200 Isolation voltage volts 250 350 500 Resistance tolerance % 5 UL recognised standard values ohms Any value in the range 1R0 to 100R is recognised. E24 preferred Thermal impedance C/watt 110 82 62 54 Ambient temperature range C -55 to +155 Note - no limiting element voltage applies maximum continuous voltage is (P.R) Physical Data Dimensions (mm) and weight (g) PCB Min Wt. Type L Max D Max f min d nom mount bend Nom centres radius ULW2 9.0 3.8 19.8 12.7 0.5 d ULW3 14.5 5.8 24.6 20.3 1.1 D 0.8 1.2 L f ULW4 13 5.6 22.8 18.9 1.0 ULW5 16.5 7.2 23.6 22.9 1.8 Construction A high purity ceramic rod is assembled with interference fit end caps to which are welded the terminations. The surge withstanding resistive element is wound on the rod and welded to the caps. Flameproof fusible cement coating is applied prior to marking with indelible ink. The components are then leadformed if required and packed. Marking ULW2, ULWP2R & ULW3 resistors are marked with five colour bands. The first four indicate value and tolerance in conformance with IEC62. The fifth yellow band denotes defined fusibility. ULW4 and ULW5 resistors are legend marked with type, value and tolerance. General Note General Note BI Technologies IRC Welwyn BI Technologies IRC Welwyn TT Electronics 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 TT Electronics own data and is considered accurate at time of going to print. All information is subject to TT Electronics own data and is considered accurate at time of going to print. www.ttelectronics.com/resistors www.ttelectronics.com/resistors TT Electronics plc TT Electronics plc 12.19 09.17UL Recognised Resistors Wirewound Resistors UL Recognised Wirewound Resistors ULW Series ULW Series Terminations 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 Solvent Resistance The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. Flammability The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload. Performance Data Maximum* Typical Load at rated power (1000 hours 25C) R% 5 3 Short term overload (5 x Pr for 5 seconds) R% 5 1 Pulse (see Pulse Performance graphs) R% 5 2 Climatic R% 5 2 Long term damp heat (56 days) R% 5 1 Climatic category 55/200/56 Temperature rapid change R% 5 1 Dry heat (1000 hours 200C) R% 5 3 Vibration R% 5 1 Robustness & solder heat R% 5 1 * Addition of 0.01 applies Thermal Performance Derating Curve Body Temperature Rise 300 100 ULW3 ULW4 250 ULW2 / ULWP2R 80 200 60 ULW5 150 40 100 20 50 0 0 0 50 100 150 200 250 300 0 1 2 3 4 5 Ambient Temperature (C) Power (W) General Note BI Technologies IRC Welwyn General Note BI Technologies IRC Welwyn TT Electronics 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 TT Electronics own data and is considered accurate at time of going to print. All information is subject to TT Electronics own data and is considered accurate at time of going to print. www.ttelectronics.com/resistors www.ttelectronics.com/resistors TT Electronics plc TT Electronics plc 09.17 12.19 Proportion of Rated Power (%) Temperature Rise (C)