High Voltage Thick Film Resistor F Series • • • • • • • ������������������ ��������������������� ���������� Termination variants Wide resistance range Good resistance stability Working voltage up to 28KV Sets available with matched characteristics Good ratio matching over wide voltage range Series connection of resistors by screw terminals ���������� �������������������� Electrical Data Power Rating @ 20°C (watts) Resistance Range (ohms) F43 0.7 F44 1.3 IRC Type Limiting Element Voltage (volts) TCR (±ppm/°C) Resistance Tolerance (%) (values>1G: TCR is 250ppm/°C) (measured at 100 volts dc) In Air In Oil 2M to 100G 4K 8K -2000 2, 5, 10 2M to 150G 14K 28K -2000 2, 5, 10 CONSTRUCTION: The Cermatox® sintered oxide based resistive thick film is fired onto the surface of a high quality ceramic onto which turned brass end caps are pressed. A helical cut is made into the film to adjust its ohmic value and finally a sleeve is fitted to provide mechanical protection and electrical insulation. Resistors for use in oil or SF6 can be supplied with a lacquer protection instead of the sleeve. TERMINATIONS: Three styles of termination are available to permit resistors to be screwed together in a series chain, with the end members having axial wires for soldering. Values (any value to special order) EIA 2% values preferred Thermal Impedance (°C/watt) Operating Temperature Range (°C) 44 -55 to 100 33 -55 to 100 Screw Terminations: Styles D and KU. See illustration. Material: Turned brass. Screw Thread: All caps are tapped UNF-10 x 4.2 deep. UNF10 is 32 TPI, 60° thread angle 4.72±0.07 mm outside diameter, 3.83 mm core diameter. Coupling Stud: All KU & TU resistors are supplied with 8 mm long screwed brass studs. MARKING: Type reference, resistance value, tolerance and data code are legend marked. Wire Terminations: Styles D and KU. See illustration. Material: Solder-coated copper wire. SOLVENT RESISTANCE: The lacquer and protective sleeve provide excellent resistance to all normal industrial cleaning solvents suitable for printed circuits. General Note IRC reserves the right to make changes in product specification without notice or liability. All information is subject to IRC’s own data and is considered accurate at time of going to print. Wire and Film Technologies Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com A subsidiary of TT electronics plc F Series Issue October 2008 Sheet 1 of 3 High Voltage Thick Film Resistor Environmental Data Typical Load @ Rated Power (1000 hrs @ 20°C) ∆R% Shelf Life (12 months @ room temperature) ∆R% Derating From Rated Power @ 20°C Noise (µV/V in decade of frequency) Voltage Coefficient of Resistance (ppm/volt) 1 0.5 zero at 100°C <2.5 <25 APPLICATION NOTES: Due to the high voltage which can appear between the end cap and any adjacent metal part, resistors should be mounted at an adequate distance from other conductors. For some high voltage applications it is required to immerse the components in oil or gas to reduce the effects or corona and surface tracking. A special lacquer is available, suitable for immersion in transformer oil or SF6. When resistors are required to be plotted, the preferred encapsulant is a silicone compound. Resistors may be screwed together as a stick to provide an assembly which will be capable of withstanding any desired voltage, providing no individual resistor is subjected to a greater stress or power dissipation than is recommended in this data sheet. For voltage dividers with a low resistance section below the medium available value of an F43 resistor, it is entirely suitable to use an RC Series resistor, available down to 1 ohm. Physical Data L F44D d dia. D L L F44TU F44KU Dimensions (Inches and (mm)) L max D max T min d nom PCB mounting centers Min Bend Radius Weight nom (g) F43D 1.00 (25.4) 0.330 (8.4) 1.260 (32.0) 0.331 (0.8) 1.252 (31.8) 0.047 (1.2) 3.1 F44D 2.0 (50.8) 0.330 (8.4) 1.260 (32.0) 0.331 (0.8) 2.252 (57.2) 0.047 (1.2) 5.6 F43KU 1.19 (30.2) 0.335 (8.5) 1.260 (32.0) 0.331 (0.8) F44KU 2.09 (53.2) 0.335 (8.5) 7.4 F43TU 1.28 (32.6) 0.335 (8.5) 5.8 2.19 (55.6) 0.335 (8.5) 8.2 IRC Type F44TU Wire and Film Technologies Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com 3.9 F Series Issue October 2008 Sheet 2 of 3 High Voltage Thick Film Resistor MATCHED SETS: Matched sets can be supplied for use as voltage dividers. These may be screwed together to form sticks and, by selecting the KU type of termination, a wire connection can be provided at each end of the stick. Inquiries are welcome for special resistors and sets when resistor length, operating voltage or resistance values is outside the catalog range. Ordering Data Specify type, reference, etc. as indicated in this example of type F44KU, 6.8Ω, 2% resistor. Sample Part No. F44 KU 6806 G 50 BLK IRC Type Termination Value Tolerance G = ±2%, J = ±5%, K = 10% Temperature Coefficient Packaging Bulk = 25 pieces per box Wire and Film Technologies Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com F Series Issue October 2008 Sheet 3 of 3