Resistors High Power MELF Resistors WRM-HP Series AEC-Q200 qualified High p ower up to 1W Tolerance down to 0.1% TCR d own to 15ppm/C High p ulse handling capabi lity AllAll partsparts araree Pb-Pb-frfreeee andand ccomplyomply withwith EUEU DirDirectivectivee 2011/65/EU2011/65/EU amendedamended bbyy (EU)(EU) 2015/8632015/863 (R(RoHS3)oHS3) Electrical Data WRM0204HP WRM0207HP Power rating at 70C watts 0.4 1 Resistance range ohms R10 1M0 Limiting element voltage volts 200 350 Maximum overload voltage volts 400 700 TCR ppm/C 15, 25, 50, 100 15, 25, 50, 100 Resistance tolerance % 0.1, 0.25, 0.5, 1, 5 Standard values E24 & E96 Thermal impedance C /W 200 140 Ambient temperature range C -55 to +155 10 Insulation resistance ohms >10 Voltage proof volts 284 497 Physical Data Dimensions (mm) and weight (g) 1 L D D1 K L Type Weight max max max min min WRM 0204HP 3.7 1.55 1.55 0.7 1.5 0.02 WRM 0207HP 6.1 2.4 2.4 1.2 2.9 0.08 Construction Terminations A metal film is deposited onto a high dissipation ceramic former to which Material Plated steel cap. tin plated terminating caps are fitted. Solderability The pure tin finish produces ageing free contacts on which low melting solders can be used. Dipped area shall be The resistor is adjusted to value by a helical cut in the film and the body is covered with a smooth and bright solder coating aerft protected by a lacquer coating. 3 seconds immersion at 215C. Marking Solvent Resistance Resistance values are colour coded with three or four bands, indicating The body protection and marking are resistant to all normal industrial value and multiplier. cleaning solvents suitable for printed circuit boards. General Note BI Technologies IRC Welwyn 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.ttelectronics.com/resistors TT Electronics plc 05.21High Power MELF Resistors WRM-HP Series TCR and Tolerance Range Tolerance (%) Type TCR (ppm/C) 5 1 0.5 0.25 0.1 100 0R1 1M0 50 0R2 1M0 1R0 1M0 10R 1M0 WRM0204HP 25 10R 1M0 15 10R 300K 100 0R1 1M0 50 0R2 1M0 1R0 1M0 10R 1M0 WRM0207HP 25 10R 1M0 15 10R 300K Performance Data Maximum Short time overload: 5s at lesser of 6.25 x rated power or 2 x LEV R% 0.15 Biased humidity: 1000hrs 85C/85%RH 10% of rated power R% 0.15 Surge test: IEC 60115-1, 10/700s at lesser of (P .R) & 2 x LEV R% 0.15 70 High temperature exposure: 1000hrs at 155C R% 0.3 Bending test: 2mm deflection for 60s R% 0.05 Resistance to soldering heat: 2605C for 10s R% 0.15 Temperature rapid change: 1000cycles -55/125C R% 0.2 Endurance: 1000hrs rated power at 70C (For endurance at 8000hrs multiply stability by 2, R% 0.25 for endurance at 225,000hrs multiply stability by 6) Mechanical shock: half-sine waveform, peak 100g, duration 6ms R% 0.1 Vibration: 5g for 20min, 12 cycles each of 3 orientations, 10-2000Hz R% 0.15 ESD: 2kV human body model R% 0.5 Solderability: 2455C for 3s >95% coverage Voltage proof: 1.42 x LEV No breakdown or flashover Pulse & Thermal Performance Single Pulse: 50 rectangular pulses applied at 60s intervals such that mean power is <10% of rated power. Maximum permitted change 1%. Continuous Pulses: Continuous rectangular pulses applied at intervals such that mean power is equal to the rated power. Maximum permitted change 1%. Single Pulse Continuous Pulses 1000 1000 100 100 0207 0207 10 10 0204 0204 1 1 0.0001 0.001 0.01 0.1 1 0.0001 0.001 0.01 0.1 1 Pulse Duration (s) Pulse Duration (s) General Note BI Technologies IRC Welwyn 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.ttelectronics.com/resistors TT Electronics plc 05.21 Peak Power (W) Peak Power (W)