Related Manuals for Keithley 3761
Summary of Contents for Keithley 3761
- Page 1 Model 3761 10-Channel Low Current Multiplexer Card User’s Manual 3761-900-01 Rev. B / January 2018 *P3761-900-01B* 3761-900-01B...
- Page 2 Keithley Instruments is strictly prohibited. These are the original instructions in English. All Keithley Instruments product names are trademarks or registered trademarks of Keithley Instruments. Other brand names are trademarks or registered trademarks of their respective holders.
- Page 3 Keithley products are designed for use with electrical signals that are measurement, control, and data I/O connections, with low transient overvoltages, and must not be directly connected to mains voltage or to voltage sources with high transient overvoltages.
- Page 4 (note that selected parts should be purchased only through Keithley to maintain accuracy and functionality of the product). If you are unsure about the applicability of a replacement component, call a Keithley office for information.
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Page 5: Table Of Contents
High impedance measurements ..................4-2 Typical applications ....................5-1 Introduction .......................... 5-1 Application considerations......................5-2 Direct measurement of capacitor leakage or insulation resistance ........5-2 Indirect measurement of capacitor leakage or insulation resistance ........5-4 Connecting multiple 3761 cards ................... 5-5 Index ........................... I-1... -
Page 6: Introduction
High-speed, low-leakage reed relays with actuation times as low as 1 ms let you use the 3761 to make accurate, low-current measurements. The 3706A supports up to six 3761 cards, for a maximum of 60 low-current channels in a single mainframe system. -
Page 7: System Switch / Multimeter Card Compatibility
The digital I/O port of the 3761 is not suitable for control of safety circuits and should not be used to control a safety interlock. Bypassing the interlock can result in personal injury or death from electric shock. -
Page 8: Contact Information
If you have any questions after you review the information in this documentation, please contact your local Keithley Instruments office, sales partner, or distributor. You can also call the corporate headquarters of Keithley Instruments (toll-free inside the U.S. and Canada only) at 1-800-935-5595, or from outside the U.S. -
Page 9: Installation And Connections
Web browser support ............... 2-3 Handling precautions Make sure to handle the 3761 carefully. Always grasp the multiplexer card by the side edges or covers. Do not touch board surfaces, components, or areas adjacent to electrical contacts. Contamination from foreign materials such as dirt, dust, and body oils can substantially lower leakage resistances, degrading card performance. -
Page 10: Card Connectors
Figure 2: Model 3761 card connectors While SMA connectors are not typically used in low-current applications, the connectors on the 3761 are compact, Teflon-insulated, and exhibit low-leakage characteristics. -
Page 11: Web Browser Support
Card edge (part of the card) Card Mounting screws (part of the card) Web browser support Web browser support for the 3761 10-Channel Low Current Multiplexer Card is not supported with the 3706A Switch System/DMM. 3761-900-01 Rev. B / January 2018... -
Page 12: General Operation
Follow these recommendations before and after applying power to the equipment: 1. Do not exceed the 3761 maximum allowable signal level as defined in the specifications. 2. Do not exceed the 3761 maximum common mode voltage of 30 V as defined in the specifications. -
Page 13: Current And Voltage Switching Applications
Model 3761 10-Channel Low Current Multiplexer Card User's Manual Current and voltage switching applications For current switching applications, each channel on the 3761 has a pair of single-pole single-throw (SPST), normally open (NO) relays. The relay pair switches signal HI between signal LO (analog ground) and output HI. - Page 14 You can also configure the 3761 for voltage switching. See the next figure for a schematic of the 3761 card configured for voltage mode.
- Page 15 Section 3: General operation Model 3761 10-Channel Low Current Multiplexer Card User's Manual You can use the following 3706A commands with the 3761 card for voltage and current mode applications. -- set slot numbers slot_3761 = 1 slot_not_3761 = 2 slot_empty = 3 -- 0=Amps-mode=default;...
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Page 16: Operation Considerations
High impedance measurements ..........4-2 Cables Shielded cables should be used with the 3761. The shield should be connected to circuit guard, analog LO. This helps prevent excessive radiation from the cables from interfering with any equipment. The cable rating must not exceed the maximum allowable signal levels as defined in the 3761 card specifications. -
Page 17: High Impedance Measurements
Model 3761 10-Channel Low Current Multiplexer Card User's Manual High impedance measurements Because of the high impedance circuits on the 3761, this card contains no user-serviceable components and should only be opened by a Tektronix factory service technician. 3761-900-01 Rev. B / January 2018... -
Page 18: Typical Applications
Low current or low voltage switching • The 3761 is field-installable in the 3706A scanner mainframe, and can be used in a variety of applications to switch low current levels. Typical applications include those where sourcing voltage and measuring current are required, such as: •... -
Page 19: Application Considerations
3761. In this test configuration, a picoammeter (IM) is connected to one of the two output connectors of the 3761 card, a shielded test fixture is used to contain the capacitors under test, and a 3762 is used to route the test and soak voltages for the capacitors under test. - Page 20 3762 closed when making the measurement. 4. When the test is complete, open the channels on the 3761 and 3762. The charge on the capacitor under test is released automatically through the discharge resistor.
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Page 21: Indirect Measurement Of Capacitor Leakage Or Insulation Resistance
Using the indirect method, the Model 3762 can be used to switch the soak voltage to each capacitor under test for specific capacitor soak times with the 3761 in current mode. When the capacitors are equal to charged and settled, the 3761 is switched to voltage mode and a new source voltage (V TEST ) is applied to the capacitors through the 3762. -
Page 22: Connecting Multiple 3761 Cards
Connecting multiple 3761 cards Two output connectors on each 3761 card let you add multiple cards to expand the size of the multiplexer by ten for each additional 3761. An additional relay isolates all circuitry on the card from the outputs when all channels are open and closes when any channel closes. - Page 23 Section 5: Typical applications Model 3761 10-Channel Low Current Multiplexer Card User's Manual Figure 8: 20-channel scanner system with two 3761 cards in ampere mode 3761-900-01 Rev. B / January 2018...
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Page 24: Index
Typical applications • 1-1, 5-1 Cables • 4-1 Unpack and inspect • 2-1 Card connectors • 2-2 Card installation • 2-2 Connecting multiple 3761 cards • 5-5 warranty • 1-2 contact information • 1-3 Web browser support • 2-3 Contact information • 1-3 Current and voltage switching applications •... - Page 25 All Keithley trademarks and trade names are the property of Keithley Instruments. All other trademarks and trade names are the property of their respective companies. Keithley Instruments Corporate Headquarters • 28775 Aurora Road • Cleveland, Ohio 44139 • 440-248-0400 • Fax: 440-248-6168 • 1-800-935-5595 • www.tek.com/keithley 3/17...