Ultra-High Value Precision Resistor 3810 Series Glass to metal seal • Low Voltage Glass Envelope • Hermetically sealed 14 • Resistance range up to 100T ohms (10 ohms) • Designed for low current (pica ampere level) measurements Flexible connecting coil • Leakage current minimised by hermetic sealing and guard ring Solder coated leads Electrical Data IRC Type 3810 Resistance Range (ohms) Limiting Element Voltage (volts) 100M to 1T 500 3811 100M to 1T 1000 3812 1T to 100M 1000 TCR Resistance (20°C - 70°C) Tolerance ppm/°C (%) Values Operating Temperature Range (°C) 10, 20 -500 to -3500 1, 2, 5, 10 EIA 2% values preferred 2, 5, 10 CONSTRUCTION: The Cermetox resistive film is fired onto a high quality ceramic substrate; brass end caps are force fitted to the substrate which is then adjusted to value with a hellical cut in the film; the leads are mechanically locked into the end caps and the assembly sealed into the glass envelope. All close tolerance units utilize two resistors connected in series within the glass envelope. High value units, type 3812, are part filled with silicone oil. the guard band is described, with application notes, in a Product Information sheet, available on request. -40 to 100 Voltage Coefficient of Resistance (measured at voltages of 100 & 500 volts) ppm/volt 100MΩ 1TΩ 100TΩ -20 -160 -10 -80 -150 -10 -80 -150 MARKING: Type reference, TCR code, resistance value and tolerance code are legend marked. Resistance value marking conforms to IEC 62. SOLVENT RESISTANCE: The glass envelope is coated with silicone and should not be subjected to solvents or their vapors. (See application notes.) PACKAGING: Each resistor is individually packed in a polythene envelope together with a card carrying measurement details and serial number. (See application notes.) TERMINATIONS: Solder-coated dumet-wire. Performance Data Typical Load at Rated Voltage (1000 hrs at 20°C) ∆R% Shelf Life (12 months at room temperature) ∆R% Resistance To Solder Heat 1 0.5 <0.1 Capacitance pF Inductance ∆R% Low inductance versions available in the range 100M to 1T 3810 3811 0.4 0.2 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 3810 Series Issue July 2008 Sheet 1 of 2 Ultra-High Value Precision Resistor APPLICATION NOTES: Each resistor is packed with a card stating nominal resistance value at 100 V applied, selection tolerance, date and serial number. Although the glass envelope is an excellent insulant and would be adequate in a dry atmosphere, the condensation which occurs in a normal atmospherewill provide a shunt resistance which will modify the very high resistance value. To minimize this effect all units are coated with silicone, and it is essential that this coating is not damaged; any handling should be by the terminations. For the same reason solvents should not be used in a damp atmosphere. If moisture develops on the body the resistor should be dried for 30 minutes at 70°C and allowed to cool for a further 30 minutes in a dry atmosphere. To avoid damage to the seal between terminations and glass, the leads must be fully supported inside the point of bending during any preforming operation. Guard Band: For details of how to use the guard band, fitted to resistors of 100GΩ and over, ask for Product Information Sheet No. 32. Non-standard Versions: Units without the glass envelope but with laquer protection are available, but will have a limited electrical performance. Measured values at a voltage other than 100V may be recorded. For non-standard items contact factory. Physical Data L T d dia. D dia. S Dimensions (Inches and (mm)) Type L max D max T min d nom S min Weight nom (g) 3810 0.984 (25.0) 0.236 (6) 1.181 (30) 0.024 (0.6) 1.220 (31) 1.5 3811 1.689 (42.9) 0.236 (6) 1.181 (30) 0.024 (0.6) 1.929 (49) 2.2 3812 1.890 (48.0) 0.236 (6) 1.181 (30) 0.024 (0.6) 2.126 (54) 2.5 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 8900 Series Issue July 2008 Sheet 2 of 2