KEI 7708 User 电路图.pdf

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1、Model 770840-Channel Differential Multiplexer with Automatic CJC Users Guide PA-744 Rev. C / 8-03 A G R E A T E RM E A S U R E O F C O N F I D E N C E RadioFans.CN 收音机爱 好者资料库 WARRANTY Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a period of

2、 1 year from date of shipment. Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batteries, diskettes, and documentation. During the warranty period, we will, at our option, either repair or replace any product that proves to

3、be defective. To exercise this warranty, write or call your local Keithley representative, or contact Keithley headquarters in Cleveland, Ohio. You will be given prompt assistance and return instructions. Send the product, transportation prepaid, to the indicated service facility. Repairs will be ma

4、de and the product returned, transportation prepaid. Repaired or replaced products are warranted for the balance of the original warranty period, or at least 90 days. LIMITATION OF WARRANTY This warranty does not apply to defects resulting from product modifi cation without Keithleys express written

5、 consent, or misuse of any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leakage, or problems arising from normal wear or failure to follow instructions. THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, I

6、NCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. THE REMEDIES PRO- VIDED HEREIN ARE BUYERS SOLE AND EXCLUSIVE REMEDIES. NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES

7、ARISING OUT OF THE USE OF ITS INSTRUMENTS AND SOFTWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF SUCH DAMAGES. SUCH EXCLUDED DAMAGES SHALL INCLUDE, BUT ARE NOT LIM- ITED TO: COSTS OF REMOVAL AND INSTALLATION, LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY

8、 PERSON, OR DAMAGE TO PROPERTY. Keithley Instruments, Inc. 28775 Aurora Road Cleveland, Ohio 44139 440-248-0400 Fax: 440-248-6168 1-888-KEITHLEY (534-8453) Sales Offi ces: BELGIUM: Bergensesteenweg 709 B-1600 Sint-Pieters-Leeuw 02-363 00 40 Fax: 02-363 00 64 CHINA: Yuan Chen Xin Building, Room 705 1

9、2 Yumin Road, Dewai, Madian Beijing 100029 8610-82251886 Fax: 8610-82251892 FINLAND: Halsuantie 2 00420 Helsinki, Finland 09-53 06 65 60 Fax: 09-53 06 65 65 FRANCE: 3, alle des Garays 91127 Palaiseau Cdex 01-64 53 20 20 Fax: 01-60 11 77 26 GERMANY: Landsberger Strasse 65 82110 Germering 089-84 93 07

10、-40 Fax: 089-84 93 07-34 GREAT BRITAIN: Unit 2 Commerce Park, Brunel Road Theale, Berkshire RG7 4AB 0118 -929 75 00 Fax: 0118- 929 75 19 INDIA: 1/5, Eagles Street Langford Town Bangalore 560 025 080 212 80-27 Fax: 080 212 80 05 ITALY: Viale San Gimignano, 38 20146 Milano 02-48 39 16 01 Fax: 02-48 30

11、 22 74 JAPAN: New Pier Takeshiba North Tower 13F 11-1, Kaigan 1-chome Minato-ku, Tokyo 105-0022 81-3-5733-7555 Fax: 81-3-5733-7556 KOREA: 2FL., URI Building 2-14 Yangjae-Dong Seocho-Gu, Seoul 137-888 82-2-574-7778 Fax: 82-2-574-7838 NETHERLANDS: Postbus 559 4200 AN Gorinchem 0183-63 53 33 Fax: 0183-

12、63 08 21 SWEDEN: c/o Regus Business Centre Frosundaviks All 15, 4tr 16970 Solna 08-50 90 46 00 Fax: 08-655 26 10 TAIWAN: 13F-3, NO. 6, Lane 99, Pu-Ding Road, Hsinchu, Taiwan, ROC. 886-3-572-9077 Fax: 886-3-572-9031 5/03 RadioFans.CN 收音机爱 好者资料库 Safety Precautions The following safety precautions shou

13、ld be observed before using this product and any associated instrumentation. Although some in- struments and accessories would normally be used with non-haz- ardous voltages, there are situations where hazardous conditions may be present. This product is intended for use by qualifi ed personnel who

14、recog- nize shock hazards and are familiar with the safety precautions re- quired to avoid possible injury. Read and follow all installation, operation, and maintenance information carefully before using the product. Refer to the manual for complete product specifi cations. If the product is used in

15、 a manner not specifi ed, the protection pro- vided by the product may be impaired. The types of product users are: Responsible body is the individual or group responsible for the use and maintenance of equipment, for ensuring that the equipment is operated within its specifi cations and operating l

16、imits, and for en- suring that operators are adequately trained. Operators use the product for its intended function. They must be trained in electrical safety procedures and proper use of the instru- ment. They must be protected from electric shock and contact with hazardous live circuits. Maintena

17、nce personnel perform routine procedures on the product to keep it operating properly, for example, setting the line voltage or replacing consumable materials. Maintenance procedures are de- scribed in the manual. The procedures explicitly state if the operator may perform them. Otherwise, they shou

18、ld be performed only by service personnel. Service personnel are trained to work on live circuits, and perform safe installations and repairs of products. Only properly trained ser- vice personnel may perform installation and service procedures. Keithley products are designed for use with electrical

19、 signals that are rated Measurement Category I and Measurement Category II, as described in the International Electrotechnical Commission (IEC) Standard IEC 60664. Most measurement, control, and data I/O sig- nals are Measurement Category I and must not be directly connect- ed to mains voltage or to

20、 voltage sources with high transient over- voltages. Measurement Category II connections require protection for high transient over-voltages often associated with local AC mains connections. Assume all measurement, control, and data I/O connections are for connection to Category I sources unless oth

21、er- wise marked or described in the Manual. Exercise extreme caution when a shock hazard is present. Lethal voltage may be present on cable connector jacks or test fi xtures. The American National Standards Institute (ANSI) states that a shock hazard exists when voltage levels greater than 30V RMS,

22、42.4V peak, or 60VDC are present. A good safety practice is to expect that hazardous voltage is present in any unknown circuit before measuring. Operators of this product must be protected from electric shock at all times. The responsible body must ensure that operators are pre- vented access and/or

23、 insulated from every connection point. In some cases, connections must be exposed to potential human con- tact. Product operators in these circumstances must be trained to protect themselves from the risk of electric shock. If the circuit is capable of operating at or above 1000 volts, no conductiv

24、e part of the circuit may be exposed. Do not connect switching cards directly to unlimited power circuits. They are intended to be used with impedance limited sources. NEVER connect switching cards directly to AC mains. When con- necting sources to switching cards, install protective devices to lim-

25、 it fault current and voltage to the card. Before operating an instrument, make sure the line cord is connect- ed to a properly grounded power receptacle. Inspect the connecting cables, test leads, and jumpers for possible wear, cracks, or breaks before each use. When installing equipment where acce

26、ss to the main power cord is restricted, such as rack mounting, a separate main input power dis- connect device must be provided, in close proximity to the equip- ment and within easy reach of the operator. For maximum safety, do not touch the product, test cables, or any other instruments while pow

27、er is applied to the circuit under test. ALWAYS remove power from the entire test system and discharge any capacitors before: connecting or disconnecting cables or jump- ers, installing or removing switching cards, or making internal changes, such as installing or removing jumpers. Do not touch any

28、object that could provide a current path to the com- mon side of the circuit under test or power line (earth) ground. Always make measurements with dry hands while standing on a dry, insulated surface capable of withstanding the voltage being measured. The instrument and accessories must be used in

29、accordance with its specifi cations and operating instructions or the safety of the equip- ment may be impaired. Do not exceed the maximum signal levels of the instruments and ac- cessories, as defi ned in the specifi cations and operating informa- tion, and as shown on the instrument or test fi xtu

30、re panels, or switching card. When fuses are used in a product, replace with same type and rating for continued protection against fi re hazard. Chassis connections must only be used as shield connections for measuring circuits, NOT as safety earth ground connections. If you are using a test fi xtur

31、e, keep the lid closed while power is ap- plied to the device under test. Safe operation requires the use of a lid interlock. 5/03 RadioFans.CN 收音机爱 好者资料库 If a screw is present, connect it to safety earth ground using the wire recommended in the user documentation. The symbol on an instrument indica

32、tes that the user should re- fer to the operating instructions located in the manual. The symbol on an instrument shows that it can source or mea- sure 1000 volts or more, including the combined effect of normal and common mode voltages. Use standard safety precautions to avoid personal contact with

33、 these voltages. The symbol indicates a connection terminal to the equipment frame. The WARNING heading in a manual explains dangers that might result in personal injury or death. Always read the associated infor- mation very carefully before performing the indicated procedure. The CAUTION heading i

34、n a manual explains hazards that could damage the instrument. Such damage may invalidate the warranty. Instrumentation and accessories shall not be connected to humans. Before performing any maintenance, disconnect the line cord and all test cables. To maintain protection from electric shock and fi

35、re, replacement components in mains circuits, including the power transformer, test leads, and input jacks, must be purchased from Keithley Instru- ments. Standard fuses, with applicable national safety approvals, may be used if the rating and type are the same. Other components that are not safety

36、related may be purchased from other suppliers as long as they are equivalent to the original component. (Note that se- lected parts should be purchased only through Keithley Instruments to maintain accuracy and functionality of the product.) If you are unsure about the applicability of a replacement

37、 component, call a Keithley Instruments offi ce for information. To clean an instrument, use a damp cloth or mild, water based cleaner. Clean the exterior of the instrument only. Do not apply cleaner directly to the instrument or allow liquids to enter or spill on the instrument. Products that consi

38、st of a circuit board with no case or chassis (e.g., data acquisition board for installation into a computer) should never require cleaning if handled according to in- structions. If the board becomes contaminated and operation is af- fected, the board should be returned to the factory for proper cl

39、eaning/servicing. ! PA-744 Rev. C / 8-03 Model 7708 40-Channel Differential Multiplexer with Automatic CJC Users Guide Keithley Instruments, Inc. 28775 Aurora Road Cleveland, Ohio 44139 (440) 248-0400 Fax: (440) 248-6168 Introduction The Model 7708 is a 40-channel differential multiplexer card with

40、the following features: DC and AC voltage measurement 2-wire or 4-wire measurement (automatically pairs switches for four wire measurements n + 20) Temperature applications (RTD, thermistor, thermocouple) Built-in cold junction reference Screw terminal connections Designed specifi cally for use with

41、 Keithleys Model 2700, 2701, and 2750 system DMMs. NOTE All references to the Model 27xx apply to the Models 2700, 2701, and 2750. WARNING Before operating the Model 27xx with an accessory card, verify that the card is properly installed and the mounting screws are tightly fastened. If the mounting

42、screws are not properly connected, an electrical shock hazard may be present. TopicPage Introduction Specifi cations. 2 Operating instructions. 2 Card confi guration Description. 3 Card connections. 4 Wiring procedure . 6 Typical connections . 7 Connection log. 9 Performance verifi cation Verifi cation test requirements . 10 Test considerations. 11 Verifi cation limits. 11 Recommended test equipment. 12 Performance verifi cation procedures . 13 Calibration Recommended test equipment. 23 Exte