MO1S

MO-S_C.qxd 7/22/04 2:19 PM Page 1 Power Metal Oxide Film Resistors MO-S Series Welwyn Components • • • Small size for power rating Can replace carbon composition in many pulse handling applications Flameproof protection Electrical Data Power rating at 70°C Restance range Limiting element voltage TCR Isolation voltage Resistance tolerance Standard values Thermal impedance Ambient temperature range watts ohms volts ppm/°C volts % °C/watt °C MO1/2S 0.5 10R - 50K 250 350 MO1S 1.0 MO2S 2.0 10R - 100K 350 350 500 5, 10 E24 preferred 80 -55 to +155 MO3S 3.0 MO5S 5.0 10R - 100K 500 700 140 110 60 35 Physical Data Dimensions (mm) and Weight (g) pcb mounting centres 10.0 12.5 15.0 20.0 30.0 Min bend radius 0.6 1.2 1.2 1.2 1.2 Wt. nom. 0.3 0.5 0.9 1.1 4.3 Type L max. MO1/2S 6.2 MO1S 9.0 MO2S 12.5 MO3S 14.5 MO5S 25.0 D max. 2.5 3.6 4.2 5.3 8.5 f min. 21.0 19.6 17.8 23.8 27.6 d nom. 0.6 0.8 0.8 0.8 0.8 d D L f Construction The tin oxide resistance element is deposited onto a high purity ceramic rod. End caps are force fitted and termination wires are welded to the end caps. The element is adjusted to the required resistance value by a helical cut; finally a cement protection is applied to the resistor body prior to marking with indelible ink. Marking MO1/2S, MO1S, MO2S and MO3S resistors are colour coded with four bands. IEC 62 colours are used. For larger sizes type reference, resistance value and tolerance are legend marked. The resistance value marking conforms to lEC 62. Solvent Resistance The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. Terminations Material Resistor sizes up to and including the MO3S use solder coated copper terminations. MO4S and MO5S use solder coated steel cored terminations. The terminations meet the requirements of IEC 68.2.21. Flammability The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload. Strength Solderability The terminations meet the requirements of IEC 115-1, Clause 4.17.3.2. 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 data and is considered accurate at time of going to print. A subsidiary of TT electronics plc Issue C · 07.04 © Welwyn Components Limited · Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email :info@welwyn-tt.com · Website: www.welwyn-tt.com 149 MO-S_C.qxd 7/22/04 2:19 PM Page 2 Power Metal Oxide Film Resistors MO-S Series Welwyn Components Performance Data Maximum Load at rated power: 1000 hrs at 70°c Shelf life: 12 months at room temperature Derating Climatic Climatic category Temperature rapid change Resistance to solder heat ∆R% ∆R% ∆R% ∆R% ∆R% 5 2 See derating curve 1 40/125/56 0.5 0.5 Application Notes % of Rated Power at 70°C MO-S Series Derating Curve 100 90 80 70 60 50 40 30 20 10 0 60 80 100 120 140 160 180 200 220 240 1. If the resistors are to dissipate full rated power, it is recommended that the terminations should not be soldered closer than 4mm from the body. 2. Due to operating temperature limitations imposed by some pcb materials, derating may be necessary. An estimate of the temperature rise to be expected can be calculated using the thermal impedance figures given under Electrical Data. 3. MO-S resistors can also be supplied pre-formed. See lead form section for details. Ambient Temp Figure 1 Packaging Our standard packaging for MO1/2S, MO1S, MO2S and MO3S is taped and ammo packed, MO5S is taped and reeled. The critical dimensions are shown in Figure 1. The component wires will not protrude beyond the outside edge of the tapes. Pre-formed resistors are supplied loose packed in plastic bags or boxes. Alternative packaging available by request. 6 c f1 b f2 6 Body Location f1 – f2 ≤ 1.4 mm Type b c MO1/2S 52 5 MO1S 52 5 MO2S 52 5 MO3S 67 10 MO5S 85 10 Standard Quantities Per Package Type Reel Ammo pack MO1/2S 5000 5000 MO1S 2500 2500 MO2S 2500 1500 MO3S 1000 1000 MO5S 700 n/a © Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com 150 Issue C · 07.04