HARS-LX_im 电路图.pdf

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1、 PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT TEL:(516)334-5959(800)899-8438FAX:(516)334-5988 534MainStreet,Westbury,NY11590 IET LABS, INC. HARS-LX SeRieS Laboratory Standard Decade Resistance Substituter User and Service Manual Copyright 2009 IET Labs, Inc. Visit for manual revision updates HARS-

2、LX im/April 2009 RadioFans.CN 收音机爱 好者资料库 PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT TEL:(516)334-5959(800)899-8438FAX:(516)334-5988 534MainStreet,Westbury,NY11590 IET LABS, INC. RadioFans.CN 收音机爱 好者资料库 WARRAntY We warrant that this product is free from defects in material and workmanship and, wh

3、en properly used, will performinaccordancewithapplicableIETspecifi cations.Ifwithinoneyearafteroriginalshipment,itisfound not to meet this standard, it will be repaired or, at the option of IET, replaced at no charge when returned to IET. Changes in this product not approved by IET or application of

4、 voltages or currents greater than those allowed bythespecifi cationsshallvoidthiswarranty.IETshallnotbeliableforanyindirect,special,orconsequential damages, even if notice has been given to the possibility of such damages. THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCL

5、UDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTIBILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. RadioFans.CN 收音机爱 好者资料库 WARninG OBSERVE ALL SAFETY RULES WHEN WORKING WITH HIGH VOLTAGES OR LINE VOLTAGES. Dangerous voltages may be present inside this instrument. Do not open the case Refer ser

6、vicing to qulifi ed personnel HIGH VOLTAGES MAY BE PRESENT AT THE TERMINALS OF THIS INSTRUMENT WHENEVER HAZARDOUS VOLTAGES ( 45 V) ARE USED, TAKE ALL MEASURES TO AVOID ACCIDENTAL CONTACT WITH ANY LIVE COMPONENTS. USE MAXIMUM INSULATION AND MINIMIZE THE USE OF BARE CONDUCTORS WHEN USING THIS INSTRUME

7、NT. Use extreme caution when working with bare conductors or bus bars. WHEN WORKING WITH HIGH VOLTAGES, POST WARNING SIGNS AND KEEP UNREQUIRED PERSONNEL SAFELY AWAY. CAUtion DO NOT APPLY ANY VOLTAGES OR CURRENTS TO THE TERMINALS OF THIS INSTRUMENT IN EXCESS OF THE MAXIMUM LIMITS INDICATED ON THE FRO

8、NT PANEL OR THE OPERATING GUIDE LABEL. Contents Chapter 1 Introduction .1 Chapter 2 Specifications .2 Model Information .3 Chapter 3 Installation .5 3.1 Initial Inspection . 5 3.2 Installation .5 3.3 Repackaging for Shipment . 5 3.4 Storage . 5 Chapter 4 Operation .6 4.1 Initial Inspection and Setup

9、 .6 4.2 Connection .6 4.2.1 General Considerations .6 4.3 Electrical Considerations .6 4.3.1 Thermal emf Considerations .6 4.4 Dial Setting .7 4.5 Power Considerations . 7 4.6 Environmental Conditions . 7 4.7 Switch Conditioning .7 4.8 Meter Shunt Applications . 8 4.9 Kelvin Bridge Applications . 8

10、Chapter 5 Maintenance .9 5.1 Maintainability and Reliability .9 5.2 Preventive Maintenance .9 5.3 Calibration .9 5.3.1 Calibration Interval .9 5.3.2 General Considerations .10 5.3.3 RequiredEquipment . 10 5.3.4 Calibration Procedure . 10 5.4 Adjustments. 11 5.4.1 Trimming Considerations .11 5.4.2 Tr

11、imming Procedure . 11 5.5 Replaceable Parts List .13 Figures and Tables Figure 1-1: HARS-LX Standard Decade Resistance Substituter .1 Figure 2-1: Typical Operating Guide Affixed to Unit .4 Figure 4-1: Kelvin Bridge Connections .8 Table 5-1: Trimming Potentiometers .12 Figure 5-1: Typical Trimmer Boa

12、rd .12 Table 5-2: Replaceable Parts List .13 Figure 5-2: HARS-LX Replaceable Parts .13 1 HARS-LX Series 1introduction Chapter 1 intRoDUCtion The Laboratory Standard (HARS-LX) Series of resistance decade substituters (Figure 1.1) is a fam- ily of instruments providing a very broad choice of high-perf

13、ormance resistance sources. Any number of decades from one to ten is available. The HARS-LX-8-0.01-RH is a direct replacement for the model RS925D. The HARS-LX substituter is a precision resistance source with excellent characteristics of accuracy, stability,temperaturecoefficient,andpowercoeffi- ci

14、ent. All these features serve to make it a laboratory resistance standard, exceeded in performance only by stand-alone standard resistors. Hermetically sealed wirewound resistors are used for 1 steps and over. These resistors are carefully conditioned under power and temperature in order to develop

15、the best stability characteristics. Actual experience has shown them to exhibit a storage sta- bility of better than 5 ppm/year, improving as they age. The low-resistance resistors are constructed with resistance wire with a minimum of copper resistance inseriestolimittemperaturecoefficienteffects.

16、Theunithasafixedminimumresistanceof10m. This is implemented by mechanically limiting the 10 m decade from going below the “1” position. In this manner, no zero resistance subtractions have to be made, and the accuracy given is for the absolute reading. The HARS-LX series employs completely enclosed

17、dust-tight very low contact resistance switches. They featuresolidsilveralloycontactsandquadruple- leaf silver alloy wipers which keep switch contact resistance to under 1 m per decade, and more im- portantly, keep switch contact resistance reproducible, insuring repeatable instrument performance. H

18、ighqualitygoldplatedtelluriumcopperbinding posts minimize the thermal emf effects which would artificiallyreflectachangeindcresistancemeasure- ments. All other conductors within the instrument, as well as the solder employed, contain no metals or junctions that contribute to thermal emf problems. Th

19、e HARS-LX is designed to allow very convenient maintenance of calibration over time. Most decades are calibratable without changing components or sol- deringresistors.Thedecadesforthe100through 100 k steps are calibrated with convenient trimmers. Trimming of the lower decades is also possible. With

20、a resolution as low as 1 m and a maximum available resistance of over 12.2 M, the HARS-LX Series may be employed for exacting precision mea- surementapplicationsrequiringhighaccuracyand stability. They can be used as components of dc and lowfrequencyacbridges,forcalibration,astransfer standards, and

21、 as RTD simulators. HARS-LX Laboratory Standard Figure 1-1: Decade Resistance Substituter 2 HARS-LX Series 2Specifications Chapter 2 SpeCifiCAtionS Forconveniencetotheuser,thepertinentspecifica- tions are given in a typical OPERATING GUIDE, liketheoneshowninFigure2.1,affixedtothecase of the instrume

22、nt. Resistor Type: Resistance wire for 0.1 steps and under; her- metically sealed, low inductance wirewound, for 1 steps and over; Minimum Resistance: 10 m 0.5 m; limited by the lowest settable position, “1”, of the 10 m/step decade. Range See Model information on next page. Resolution See Model inf

23、ormation on next page. Accuracy: (20 ppm + 0.5 m); at 23C, 4-terminal “true- ohm” measurement, 30-70% RH, absolute reading, no zero subtraction required, SI traceable. Stability: (20 ppm + 0.5 m)/year; 1010 . Resistance Temperature Coefficient: 20 ppm/C for 1 steps and under; 15 ppm/C for 10 steps;

24、3 ppm/C for 100 steps and over; +50 /C for wiring and switch resistance. Resistance Power Coefficient: 1 ppm/mW for 0.1 steps and under; 0.4 ppm/mW for 1 steps; 0.3 ppm/mW for 10 steps; 0.1 ppm/mW for 100 steps and over; +50 /W total for wiring and switch resistance. Breakdown Voltage: 1500 V peak t

25、o case. Operating Temperature: 0C to 55C. Storage Temperature: -40C to 70C. Switch Type: 11 position “0”-“10” (12 position, “0”-“11” for highest decade); multiple solid silver contacts; dust tight diallyl-phthalate body. To allow con- tinuous rotation, a blank position is added on most decades. Term

26、inals: Four, 5-way, gold-plated ,tellurium-copper bind- ing posts with low thermal emf and low resistance, for four terminal Kelvin measurements, plus one binding post connected to the case for shielding. Rear outputs are available as an option. Dimensions: Rack model: 48.3 cm W x 17.8 cm H x 19.7 c

27、m D (19.0” x 7.0” x 7.75”) Weight: 5.1 kg (13 lb) 3 HARS-LX Series 3Specifications MoDeL infoRMAtion HARS-LX-1-0.0010.0110.001 HARS-LX-1-0.010.110.01 HARS-LX-1-0.1110.1 HARS-LX-1-11011 HARS-LX-1-10100110 HARS-LX-1-1001k1100 HARS-LX-1-1K10k11k HARS-LX-1-10K100k110k HARS-LX-1-100K1M1100k HARS-LX-1-1M1

28、0M11M HARS-LX-2-0.0010.1120.001 HARS-LX-2-0.011.120.01 HARS-LX-2-0.11120.1 HARS-LX-2-111021 HARS-LX-2-101.1k210 HARS-LX-2-10011k2100 HARS-LX-2-1K110k21k HARS-LX-2-10K 1.1 M210k HARS-LX-2-100K 11 M2100k HARS-LX-3-0.0011.1130.001 HARS-LX-3-0.0111.130.01 HARS-LX-3-0.111130.1 HARS-LX-3-1 1.11 k 3 1 HARS

29、-LX-3-1011.1k310 HARS-LX-3-100111k3100 HARS-LX-3-1K 1.11 M 3 1 k HARS-LX-3-10K11.1M310k Modeltotal Resistance () no. of Decades Resolution () OPTIONS Model HARS-LX-4-0.00111.1140.001 HARS-LX-4-0.01111.140.01 HARS-LX-4-0.11.111k40.1 HARS-LX-4-1 11.11 k 4 1 HARS-LX-4-10111.1k410 HARS-LX-4-1001.111M410

30、0 HARS-LX-4-1K 11.11 M 4 1 k HARS-LX-5-0.001111.1150.001 HARS-LX-5-0.011.1111k50.01 HARS-LX-5-0.111.111k50.1 HARS-LX-5-1 111.11 k 5 1 HARS-LX-5-101.1111M510 HARS-LX-5-10011.111M5100 HARS-LX-6-0.0011.11111k60.001 HARS-LX-6-0.0111.1111k60.01 HARS-LX-6-0.111.111k60.1 HARS-LX-6-1 1.111 11 M 6 1 HARS-LX-

31、6-1011.1111M610 HARS-LX-7-0.001 11.11111k70.001 HARS-LX-7-0.01111.1111k70.01 HARS-LX-7-0.11.111111M70.1 HARS-LX-7-1 11.111 11 M 7 1 HARS-LX-8-0.001111.11111k80.001 HARS-LX-8-0.011.2111111M80.01 HARS-LX-8-0.11.211111M80.1 HARS-LX-9-0.0011.21111111M90.001 HARS-LX-9-K-RM1.21111111M90.001 HARS-LX-9-0.01

32、12.1111111M90.01 HARS-LX-10-0.001 12.111 111 11 M100.001 HARS-LX-11-0.001 121.111 111 11 M110.001 optionS: RH 10m rheostatforlowestdecades,20 resolution. Ro Rear output binding posts RM Rack-mountable case for standard 19” rack 4 HARS-LX Series 4Specifications Typical Operating Guide Affixed to Unit

33、Figure 2-1: 5 HARS-LX Series 5installation Chapter 3 installation initial inspection3.1 IET instruments receive a careful mechanical and electrical inspection before shipment. Upon receipt, verify that the contents are intact and as ordered. The instrument should then be given a visual and operation

34、al inspection. If any shipping damage is found, contact the carrier and IET Labs. If any operational problems are en- countered, contact IET Labs and refer to the warranty at the beginning of this manual. Save all original packing material for convenience in case shipping of the instrument should be

35、come necessary. installation3.2 For a rack mounted model, installation in a 19 inch rack may be made using the slots in the rack mount- ing ears. A mounting location that does not expose the unit to excessive heat is recommended. For bench modelsthereisnorequiredinstallation. Since this is a high ac

36、curacy instrument, it is rec- ommended that a space be provided that would not expose it to mechanical abuse and keep it maintained at laboratory standard temperatures near 23C. Repackaging for Shipment3.3 If the instrument is to be returned to IET Labs, contact the Service Department at the number

37、or address, shown on the front cover of this manual, to obtain a “Returned Material Authorization” (RMA) number and any special shipping instructions or assistance. Proceed as follows: Attach a tag to the instrument identifying the 1. owner and indicate the service or repair to be accomplished. Incl

38、ude the model number, the full serial number of the instrument, the RMA number, and shipping address. Wrap the instrument in heavy paper or 2. plastic. Protect the front panel and any other protru-3. sions with cardboard or foam padding. Place instrument in original container or 4. equallysubstantia

39、lheavycarton. Use packing material around all sides of 5. instrument. Seal with strong tape or bands.6. Mark shipping container “DELICATE 7. INSTRUMENT,” “FRAGILE,” etc. Storage3.4 If this instrument is to be stored for any lengthy period of time, it should be sealed in plastic and stored in a dry location. It should not be subjected to tem