FLUKE 80K-40 Instruction 电路图.pdf

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1、Maintenance Performance Test Verify the probe accuracy by measuring a 25 kV dc 0.25% voltage source. When used with a compatible dc voltmeter, the probe should measure the source with 1% accuracy. No calibration adjustments are provided. Cleaning Use a soft cloth dampened in distilled water to clean

2、 the 80K-40. Never use solvents or abrasive cleaners. Make sure the 80K-40 is dry before reuse. LIMITED WARRANTY add 1% at 10C 30C to 45C. (For total measurement accuracy add accuracy specification of voltmeter being used.) 0 kV to 35 kV to 40 kV: 2%. Accuracy AC: 60 Hz, 5%. Safety: Meets IEC 1010-2

3、-031:1993, Type B, 40 kV dc or, peak ac, 28 kV rms ac, Overvoltage Category I (voltages derived from limited energy transformer). * The input impedance of Autoranging Fluke handheld digital multimeters varies as a function of range. The only range that deviates significantly from 10 M is the 3V (Mod

4、els 21, 23, 25, 27, 70, 73, 75, 77) or 4V (Models 10, 11, 12, 29, 79, 83, 85, 86, 87, 88) range where the impedance is 11.11 M. To enhance the measurement accuracy when using this range, apply a correction factor of 0.99, i.e. multiply the displayed reading by .99. This probe is intended for low ene

5、rgy applications such as CRT and similar circuits. Above 2000 meters altitude, and up to 5000 meters, derate linearly the working voltage from 40 kV peak to 28 kV peak, and derate linearly the transient overvoltage from 80 kV peak to 57 kV peak. Transient overvoltage refers to micro-second duration

6、impulses caused by lightning or load switching. See International Electrotechnical Commission Publication 664-1980, Clause 3.9 Table II, and Appendix A. Measurement Considerations Before attempting to use the 80K-40, the following paragraphs should be read and understood. Particular attention should

7、 be given to Operator Safety. PN 481978 January 1978, Rev.9, 3/97 1978, 1996, 1997 Fluke Corporation, All rights reserved. Printed in U.S.A. All product names are trademarks of their respective companies. RadioFans.CN 收音机爱 好者资料库 Operator SafetyW Indicates the operator must refer to an explanation in

8、 this manual. Indicates terminals at which lethal voltages may exist. Warning To avoid damage or electric shock: Use within ratings and under dry (no condensation) conditions. The 80K-40 user should be familiar with, and exercise, all possible high voltage safety practices. When making a measurement

9、, never make body contact with the probe tip or the red portion of the probe. Always hold the probe by its black handle. Before making a measurement, make sure that the tab side of the output connector is connected to the voltmeters low input terminal. The clip lead must be attached to earth ground.

10、 Voltmeter Compatibility Accuracy of the meter is not included in the accuracy of the probe, and must be added to the probe accuracy to determine system accuracy. The 80K-40 is mechanically compatible with any ac or dc voltmeter or multimeter capable of accepting a standard spaced, 0.75 (19mm) doubl

11、e, banana plug, having standard, .160 (4mm) plugs. The 80K-40 probe is electrically compatible with any ac or dc voltmeter or multimeter that has an input impedance of 10 M 1%. Voltmeters or multimeters with other input impedances require the use of an external shunt or a correction factor to obtain

12、 an accurate measurement. Higher impedance voltmeters or multimeters should be equipped with a shunt, and lower impedance voltmeters or multimeters should be assigned correction factors. Applicable formulas follow: a. The following formula is used to determine the value of an external shunt resistor

13、 (meter impedance 10 M): Rs Rm x 10 Rm10 = Where: Rs = Shunt resistance in M Rm = Voltmeter input impedance in M (10 M) Example: If RM = 20 M, Rs 20 x 10 20 10 = 200 10 = 2.0M= b. Use the following formula to calculate a correction factor (meter impedance 10 M): Cf 1.11 + Rm 1.11 x Rm = Where: Cf=Co

14、rrectionfactor (multiplier for meter reading) Rm = Voltmeter input impedance in M Example: If Rm = 1 M, Cf 1.11 + 1 1.11 x 1 = 2.11 1.11 =1.901= Therefore: A meter reading of 0.526 volts represents an input of: 0.526 x 1.901 = 1 or 1 kV. Circuit Loading The 80K-40 represents a 1000 M load to the cir

15、cuit being measured, or 1 A per 1 kV. Table 1 shows the circuit loading and input/output characteristics of the probe over its measurement range. Table 1. 80K-40 Circuit Loading and Input/Output Characteristics Input VoltageLoading CurrentOutput Voltage 10V 100V 1 kV 10 kV 20 kV 30 kV 40 kV 10 nA 10

16、0 nA 1A 10 A 20 A 30 A 40 A 10 mV 100 mV 1V 10V 20V 30V 40V Operation Use the following procedure to operate the 80K-40: 1. Select and energize a compatible voltmeter. 2. Equip the voltmeter with a suitable shunt, if required. 3. Select an appropriate voltage range (1 volt reading per 1000 volt inpu

17、t. See Table 1). 4. Connect the probes output leads to the voltmeter input terminals. 5. Connect the probes clip lead to ground. See OPERATOR SAFETY. 6. Connect probe tip to circuit being measured and observe voltmeter reading. Apply correction factor to reading when necessary. Theory Of Operation T

18、he 80K-40 High Voltage probe, is designed to extend the voltage measurement range of an ac/dc voltmeter up to 40,000 volts. Electrically, the probe is a passive attenuator as shown in Figure 1. Its high input impedance (1000 M), as well as its accuracy and stability characteristics are achieved thro

19、ugh the use of special thick film resistors. When the probe is connected to a voltmeter with a 10 M input resistance the probe becomes an accurate 1000:1 divider. Notice that the divider depends upon a ground lead to complete the low side of the circuit path. Therefore, this connection must always be secure before attempting a voltage measurement. Otherwise, instrument damage or a shock hazard will result. Probe Tip Ground Lead Replacement Resistor Kit PN 939335 10M 80K-40DC Voltmeter HI LO Figure 1. 80K-40 Simplified Circuit Diagram RadioFans.CN 收音机爱 好者资料库