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Computer-Based
Instruments
NI 4050 User Manual
Digital Multimeter Card for PCMCIA
NI 4050 User Manual
March 2000 Edition
Part Number 321427C-01
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Worldwide Technical Support and Product Information www.ni.com National Instruments Corporate Headquarters 11500 North Mopac Expressway Austin, Texas 78759-3504 USA Tel: 512 794 0100 Worldwide Offices Australia 03 9879 5166, Austria 0662 45 79 90 0, Belgium 02 757 00 20, Brazil 011 284 5011, Canada (Calgary) 403 274 9391, Canada (Ontario) 905 785 0085, Canada (Québec) 514 694 8521, China 0755 3904939, Denmark 45 76 26 00, Finland 09 725 725 11, France 01 48 14 24 24, Germany 089 741 31 30, Gr
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Important Information Warranty The NI 4050 is warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor. The media on which you receive National Instruments software are warranted not to fail to execute programming instructions, du
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Compliance FCC/Canada Radio Frequency Interference Compliance* Determining FCC Class The Federal Communications Commission (FCC) has rules to protect wireless communications from interference. The FCC places digital electronics into two classes. These classes are known as Class A (for use in industrial- commercial locations only) or Class B (for use in residential or commercial locations). Depending on where it is operated, this product could be subject to restrictions in the FCC rules. (In
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• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. • Consult the dealer or an experienced radio/TV technician for help. Canadian Department of Communications This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations. Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada. European Union - Compliance to EEC Directives Reade
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Conventions The following conventions are used in this manual: » The » symbol leads you through nested menu items and dialog box options to a final action. The sequence File»Page Setup»Options directs you to pull down the File menu, select the Page Setup item, and select Options from the last dialog box. This icon denotes a note, which alerts you to important information. This icon denotes a caution, which advises you of precautions to take to avoid injury, data loss, or a system crash. bold
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Contents Chapter 1 Taking Measurements with the NI 4050 Cable and Probes ...........................................................................................................1-1 Introduction to the VirtualBench-DMM Soft Front Panel.............................................1-3 Use the Soft Front Panel ................................................................................................1-5 Measure DC and AC Voltage................................................................
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Contents Appendix A Specifications Appendix B Technical Support Resources Glossary Index Figures Figure 1-1. Installing the NI 4050 and Cables......................................................... 1-2 Figure 1-2. NI-DMM Soft Front Panel.................................................................... 1-3 Figure 1-3. Digits of Precision................................................................................. 1-5 Figure 1-4. Connecting Probes for Voltage Measurement .................
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1 Taking Measurements with the NI 4050 Thank you for buying a National Instruments 4050 digital multimeter card. A system based on the NI 4050 offers the flexibility, performance, and size that makes it ideal for service, repair, and manufacturing as well as for use in industrial and laboratory environments. The NI 4050, used in conjunction with your computer, is a versatile, cost-effective platform for high-resolution measurements. For the most current versions of manuals and example prog
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Chapter 1 Taking Measurements with the NI 4050 Portable Computer PCMCIA Slot NI 4050 Accessory Cable Probes Figure 1-1. Installing the NI 4050 and Cables The test probes connect to the NI 4050 accessory cable via shrouded banana jacks. The shrouds around the banana jacks prevent you from contacting potentially hazardous voltages connected to the test probes. You can also connect the cable to standard, unshrouded banana jack probes or accessories; however, use unshrouded probes or accessorie
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Chapter 1 Taking Measurements with the NI 4050 Introduction to the VirtualBench-DMM Soft Front Panel The following sections explain how to make connections to your NI 4050 and take simple measurements using the VirtualBench-DMM, as shown in Figure 1-2. To launch the soft front panel, select Start»Programs» National Instruments DMM»Soft Front Panel. Figure 1-2. NI-DMM Soft Front Panel The following text describes the options available on the soft front panel. Refer to Help»Online Reference lo
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Chapter 1 Taking Measurements with the NI 4050 The Function selector allows you select a measurement mode. Select Edit»Settings and click on the tabs for Current and Resistance or Temperature to control the data type acquired by VirtualBench-DMM. DC volts measures the DC component of a voltage signal. AC volts measures the AC component of a voltage signal. DC current measures the DC component of a current source. AC current measures the AC component of a current source. 2-wire measures resista
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Chapter 1 Taking Measurements with the NI 4050 % selects the percentage calculation. VirtualBench-DMM expresses the displayed reading as a percent deviation from the reference value entered in the Math Settings. Refer to Help»Online Reference, Math Settings topic for more information about dB, dBm, mX+B, and percentage calculations. The log button enables data logging. To configure the datalog file and log interval, select Edit»Settings. Refer to Help»Online Reference, Logging Measurements
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Chapter 1 Taking Measurements with the NI 4050 The NI 4050 is protected against damage from voltages within ±250 VDC or 250 V in all ranges. You should never apply voltages rms above these levels to the inputs. HI HI DC Voltage AC Voltage 250 V 250 V + MAX. MAX. Source Source – LO LO Figure 1-4. Connecting Probes for Voltage Measurement 2. Select the mode you will measure: •DC Volts •AC Volts 3. Select the range for your measurement or autoranging: • DC Volts—± 20 mV, ± 200 mV, ± 2 V, ± 25 V,
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Chapter 1 Taking Measurements with the NI 4050 HI 250 V Resistor MAX. LO Figure 1-5. Connections for Resistance Measurement 2. Select 2-wire resistance mode. 3. Select the range for your measurement—200 Ω, 2 kΩ, 20 kΩ, 200 kΩ, 2 MΩ, 200 MΩ, or autorange. The value indicator indicates the resistance measured. See the 2-Wire Resistance Measurements section of Chapter 2, NI 4050 Operation, for more information on 2-wire resistance measurements. Measuring the Voltage Drop Across a Diode The NI 4
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Chapter 1 Taking Measurements with the NI 4050 2. Select diode mode. 3. Select the range for your measurement. Only the 2 V range is available for diode measurement. The value indicator will indicate the voltage drop measured. If the display indicates 2.200 VDC, the diode is either reverse biased or defective. See the Diode Measurements section of Chapter 2, NI 4050 Operation, for more information on diode measurements. Measure Current You can use the NI 4050 to measure current with an optio
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Chapter 1 Taking Measurements with the NI 4050 Measure Temperature You can measure temperature using common temperature transducers such as resistive temperature devices (RTD) and thermistors. You can measure transducers in the 2-wire resistance mode, as shown in Figure 1-8. Although the soft front panel does not support temperature measurements, you can convert and scale the transducer value to temperature programmatically through software. Note The NI 4050 for PCMCIA does not support 4-wi
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2 NI 4050 Operation This chapter contains safety instructions, measurement fundamentals and concerns, and scanning information. Safety Instructions Cautions To avoid personal injury or damage to electronic equipment, observe the following: Do not operate this instrument in an explosive atmosphere or where there may be flammable gases or fumes. Equipment described in this document must be used in an Installation Category II environment per IEC 664. This category requires local level supply ma
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Chapter 2 NI 4050 Operation Measurement Fundamentals Warm Up The required warm-up time for the NI 4050 is 30 minutes. This warm-up time is important because measurements made with the NI 4050 multimeter can change with temperature. This change is called a thermal drift and affects your accuracy. To minimize the effects of thermal drift and ensure the specified accuracies, take all measurements after the NI 4050 has had a chance to fully warm up. Depending on your environment, the NI 4050 c
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Chapter 2 NI 4050 Operation Input Ranges The NI 4050 has five input ranges available for measuring DC voltages. These ranges are ±20 mV, ±200 mV, ±2.0 V, ±25V, and ±250 V. Each range has a 10% overrange, except for the 250 V range. The 250 V and 25 V input ranges have a 1 MΩ input impedance; the 2 V, 200 mV, and 20 mV ranges have an input impedance greater than 1 GΩ. Take these values into consideration when measuring high-impedance sources. When the NI 4050 is powered off, the 250 V and 2