Radial Ceramic Case Resistors Wirewound / Metal Oxide SQM Series 2 to 10 watts Resistance 0R1 to 200K High overload capability Flameproof case Small PCB footprint RoHS compliant Electrical Data SQM2 SQM3 SQM5 SQM7 SQM10 Power rating at 70C watts 2 3 5 7 10 Wirewound 0R1 - 27R 0R1 - 39R 0R1 - 47R 0R1 - 680R 0R1 - 910R Resistance range ohms Metal Oxide 30R 33K 43R 56K 51R 100K 750R - 200K 1K0 - 200K Limiting element voltage volts dc or ac rms 150 300 350 500 750 Thermal impedance C /watt 50 45 30 28 23 Isolation voltage volts 1000 TCR ppm/C <20R: 400, 20R: 350 Resistance Tolerance % 5 Standard Values E24 Ambient temperature range C -55 to +155C Physical Data (all dimensions in mm, weights in g) L P d W D Weight Type d 1.0 1.0 Nom. 1 .0 1 .0 0.05 SQM2 20 11.5 7.5 5 0.7 4.3 W P SQM3 25 12.5 8.5 5 0.7 5.6 51 SQM5 25 12.5 9 5 0.8 6.3 SQM7 38 12.5 9 5 0.8 10.7 D 51 L SQM10 50 12.5 9 5 0.8 13.4 Leads centered on SQM2, SQM3, SQM5 Leads offset as shown on SQM7, SQM10 Construction A high purity ceramic rod, with force fit end caps onto which is wound a wire element: or a deposited metal oxide film (depending on value). The element is fitted into a ceramic case with fireproof insulation cement. General Note Welwyn Components 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 TT electronics plc 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 05 . 08Radial Ceramic Case Resistors Wirewound / Metal Oxide SQM Series Termination Details: Material The 100% Sn finish copper lead wires are internally welded to the resistance element end caps. Solderability The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2 Strength The terminations meet the requirements of IEC 86.2.21 Marking: Type reference, resistance value and tolerance are legend marked onto the upper surface. Flammability: The resistor will not burn under any condition of applied temperature or overload. Solvent resistance: The body protection and marking are resistant to all normal industrial solvents suitable for printed circuits. Performance Data Maximum Load at rated power (1000hrs at 70C) R <100K, 5% 100K, 10% Derating from rated power at 70C See Graph Short term overload * R 5% +0.05 5% +0.05 Damp heat steady state (56 days, 40C, 90% RH) R Temperature rapid change (5 cycles -55C to +155C) R 2% +0.05 Resistance to solder heat R 1% +0.05 No evidence of flashover, mechanical damage, Voltage Proof (1kV for 60s) arcing or insulation breakdown Solderability Min. 95% coverage * Wirewound: the lower of 5x rated power, or 2.5x LEV for 5s Metal Oxide: the lower of 6.25x rated power, or 2.5x LEV for 5s Derating Curve P/Pr 100% 60% 0% -55 70 155 275 T (C) Ordering Procedure Example: SQM3 at 1.2 kilohms and 5% tolerance bulk packed in a box of 3000 pieces S Q M 3 1 K 2 J B 3 Type Value (use IEC62 code) Tolerance (use IEC62 code) J 5% Packing B3 SQM2, 3 3000 / box B2 Bulk SQM5 2000 / box Standard B1 SQM7, 10 1000 / box 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 05 . 08