1. Rockwell Automation Newark Safety and Product Training Maggie Stumpfl 2012

2. Agenda Electrical Measurement Safety Measurement Basics DMM’s and Accessories (233 and Clamps) Process Tools (789) Oscilloscopes (190-204) Fluke Website and Support

3. Electrical Measurement Safety Arc Flash –What is Arc Flash? –How does Arc Flash happen? –Has anyone experienced Arc Flash? Fluke Safety Video

4. Electric Shock How much current is lethal? –For a 150 pound human: At 10mA muscular paralysis occurs At 30mA respiratory paralysis occurs Between 75 and 250mA for exposure exceeding 5 seconds the heart can no longer function. Higher currents stop the heart faster. What voltage is required to generate these currents? –The resistance under the skin from hand-to-hand is about 1000 Ω 30 Volts will cause 30mA to flow –Your skin protects you up to about 600V where the resistance of skin ceases to exist If the skin is wet or cut resistance drops dramatically

5. Measurement Categories The level and energy of voltage impulses is dependent on the location. The closer the location is to the power source, the higher the available fault current, the higher the category. IEC 61010 defines four locations or categories: CAT IV“Origin of installation” Utility level and any outside cable run CAT IIIDistribution wiring, including “mains” bus, feeders and branch circuits; permanently installed loads CAT IIReceptacle outlet circuit, plug-in loads CAT IProtected electronic circuits

6. Category Locations

7. Electrical Measurement Basics

8. Instrument Specifications –Digits: 3 ½, 4 ½, etc. Example: 3 1/2: starting from the least significant digit, 3 “full” digits from 0-9, 1 “half” digit at less than 9. Ex: 1999 –Counts: 3200, 4000, 5000, etc. 3200 count display reads 0-3199 6000 count display reads 0-5999 –233 and 789 are 3 ½ digit meters 233 – 6000 counts 789 – 4000 counts 5000 Counts 3 ½ Digits

9. Electrical Measurement Basics –Resolution The smallest change in the measured value that can be observed –Resolution is a function of range and counts »Example: The 233 DMM has a resolution of 0.001V on the 6 Volt range. Range 6.0V Resolution = = = 0.001V Counts 6000 To maximize resolution choose the lowest possible range

10. Electrical Measurement Basics Accuracy –Closeness with which an instrument reading approaches the true value –Expressed as a percentage of reading + number of counts Reading error Range error –Example: Model 233 DMM DC Voltage Accuracy = +/- (0.25% + 2) Reading 1.000 Volt on the 6.0 Volt Range Accuracy would be Accuracy = +/- (0.25% * 1.0V) + (2 * 0.001V) = +/- (0.0025V) + (0.002V) = +/- (0.0045V) True value is between 0.9955V and 1.0045V

11. Electrical Measurement Basics Averaging Meters vs. True RMS Meters –Imagine this simple circuit: –The voltage across the resistor will look like this: V avg, the average voltage is 5.0 Volts –The current through the resistor will look like this: I avg, the average current is 0.5 Amps –The power dissipated will look like this: P avg, the average power is 5 Watts –Power = I*V, but I avg * V avg = 2.5 Watts ≠ P avg, Why?

12. Electrical Measurement Basics

13. Measuring True RMS is important –Measurement with an averaging meter can yield incorrect results. Averaging meters will report the correct AC value only when measuring a perfect sine wave –Any distortion in the sine wave will result in an incorrect reading with an Averaging Meter True-rms Correct Average Correct 10 % High 40 % low 5-30 % low Input Signal Response to sine wave Response to square wave Response to single phase diode rectifier Response to 3 phase diode rectifier

14. Electrical Measurement Basics What causes non-sinusoidal waveforms? –Harmonics: multiples of the waveform fundamental frequency E.g., a third harmonic of 60Hz is 180Hz –Switching-mode power supplies (PC’s, office equipment) –Light switch dimmers and electronic ballasts –Variable Speed Drives Always use a True RMS Meter Time Domain Frequency Domain

15. Electrical Measurement Basics Crest Factor –What is Crest Factor? CF = Peak / RMS Value CF for ideal sine wave = 1.414 –Crest factor is an indication of harmonics For current or voltage measurements, the higher the CF, the greater the waveform distortion. CF spec is important for accurate measurements. It is only specified for true-RMS products. C.F. = 1.43 C.F. = 2.39 C.F. = 4.68

16. Common Mode Rejection Ratio CMRR specifies how well an instrument rejects signals that appear at both the high and low input terminal –Specified in dB (20*Log(Applied/Observed)) –Example: The 233 DMM DCV CMMR is 100dB 20*Log(Applied/Observed) = 100dB Log(Applied/Observed) = 5 Applied/Observed = 10 5 = 100,000 –So if 100V is applied to both the hi and low terminal of the 233 a measured value of 100V/100,000 = 1mV could be observed

17. Normal Mode Rejection Ratio NMRR is a measure of how well the instrument can reject noise between the low and high input terminals –This is a DC Volts specification only –DMM’s are typically built to reject 50 and 60 Hz signals while in DC Mode –The 233 DMM NMMR specification is 60dB at 50 or 60 Hz –60dB equates to a ratio of 1000 This means the 233 rejects all but 1/1000 th of any 60 Hz noise between the input terminals

18. DMM’s and Accessories 233 Remote Display True RMS Multimeter i2000 flex AC Current Clamp i1010 AC/DC Current Clamp

19. 233 DMM CAT Rating All Fluke CAT Rated Products will be indicated at the input terminals 233 DMM CAT III 1000 V CAT IV 600V

20. 233 DMM Measurement Functions AC Volts/Hz DC Volts Secondary Function AC/DC 600mV Range Resistance/Continuity Power Off Hazardous Voltage Indicator Capacitor/Diode Temperature AC Amps/Hz DC Amps

21. 233 DMM Voltage Measurements How does a DMM measure voltage? –A DMM uses a dual slope integrating Analog to Digital Convertor (ADC) –The DMM applies the unknown signal to a capacitor for an exact amount of time –The DMM then discharges the capacitor –The amount of time taken to fully discharge the capacitor is proportional to the measured voltage DMM’s use a Microprocessor with a very accurate clock

22. Voltage Measurement Considerations Input Impedance –What is the input impedance (resistance) of a voltmeter? An ideal voltmeter has infinite input impedance –Real voltmeters have specified input impedances The 233 has an input impedance of 10 MΩ when measuring DC Volts –Why is this important…measurement error: 10 MΩ DMM 10 MΩ 12 Volts What will this DMM read?

23. Voltage Measurement Considerations 10 MΩ DMM 10 MΩ 12 Volts 10 MΩ

24. 233 DMM Frequency Measurements 5 Hz to 50 kHz for VAC and VDC 45 Hz to 5kHz for AC Amps

25. 233 Resistance and Continuity Functions How do DMM’s measure Resistance? –The meter supplies voltage to the circuit (233 Open Circuit Voltage is 2.7 Volts DC) –Presence of external voltage in circuit being measured causes meaningless readings and can damage a meter without overload protection –How it works: Measured V1 across a precision R1 is compared to measured V2 across an unknown Rx –233 Resistance Measurement Range is from 0.1 to 40 MΩ Continuity Function –Performs Resistance measurement also produces audible beep when a close circuit is sensed

26. 233 Capacitance and Diode Functions

27. 233 Temperature Measurement Measures temperature using a Type-K Thermocouple –A Thermocouple is a device consisting of two different metal alloys that produce a voltage proportional to temperature –Multiple Type-K probes available –233 Temperature range -40 ºC to + 400 ºC –RANGE button allows switching between Fahrenheit and Celsius scales

28. 233 Current Measurements 233 can measure current directly but the circuit must be broken and must use proper inputs Current Clamps are more commonly used –Current Clamp Advantage: Do not need to break the circuit –Current Clamp Disadvantages: Less Accurate Current must be calculated Phase shift (models that produce voltage)

29. Type of Current Clamps Current Transformer –Only functions with AC signals –Acts like the secondary winding of a transformer –Needs no external power –Produces current (scales current: 1mA/A, 10mA/A, etc.) or voltage (scales voltage: 1mV/A, 10mV/A, etc.) Hall Effect Sensor –Measures AC or DC by sensing magnetic field –Requires external power –Produces voltage (scales voltage: 1mV/A, 10mV/A, etc.) Flexible Current Transformer –Only functions on AC signals –Requires external power –Produces voltage (scales voltage: 1mV/A, 10mV/A, etc.)

30. Other 233 DMM Features Hazardous Voltage Indicator Illuminates when voltages exceed 30V or the meter is in a voltage overload condition Backlight Button RANGE Button Allows switching between auto and manual ranging and selecting ranges MIN MAX Button Captures Minimum, Maximum and Average and allows switching between values HOLD Button Allows measured value to be retained on display

31. 233 Batteries and Fuse Batteries –2 AA in remote head –3 AAA in base –Two low battery indicators (one for head, one for base) Fuse Replacement

32. 233 Remote Display Optical communication when attached to Base –Conserves battery life 2.4 Ghz ISM Band when detached –10 meter range

33. Process Tools (789) 789 is a full featured DMM Differences from the 233 –No Remote Display –No capacitance measurement –No temperature measurement –AutoHold Holds until a new stable reading is available –Has REL capability Allows for measurement of an offset value that will be subtracted from measured value

34. 4-20 mA Loops 4-20 mA Loops are used to control processes and equipment Transmitters receive input from sensors and regulate the current between 4-20mA Controllers interpret the 4-20mA signal and control equipment and processes Why 4-20 mA? –If the controller reads 0 mA then it recognizes a hardware failure –Current will remain constant even when flowing over very long distances 24 Volt Loop Power 24 Volt Loop Power

35. Testing 4-20 mA Loops Using Loop Power the 789 can replace 24 Volt power supply 24 Volt Loop Power

36. Testing 4-20 mA Loops Using Source the 789 can source 4-20 mA signals to the controller directly 24 Volt Loop Power

37. Testing 4-20 mA Loops Using Simulate the 789 can simulate the transmitter 24 Volt Loop Power 24 Volt Loop Power

38. Testing 4-20 mA Loops In addition to being a powerful DMM, the 789 can –Measure 4-20 mA signals –Source 4-20 mA signals –Simulate 4-20 mA signals –Measure 24 V loop voltage –Supply 24 V loop voltage The 789 performs many functions…

39. 789 Batteries and Fuse 4 AA Batteries Low Battery Indicator

40. Fluke 190-204 Oscilloscope 4 Isolated Channels 200 Mhz Bandwidth CAT III 1000 CAT IV 600 Rated 2.5 GS/s sample rate Connect-and-View™ IP-51 Rated

41. Oscilloscopes Electrical Signals are measured in three domains X axis, time (Seconds) Y axis, Amplitude (Volts, dB) Z axis, Frequency (Hertz) 110.56 Vac Volts time A multimeter precisely measures a signals amplitude An osciloscope displays a signal amplitude change over time A spectrum analyzer displays a signal power level (amplitude) with respect to frequency dB Frequency

42. What is a multimeter? A Multimeter accurately displays discreet Volts, Ohms and Amp measurements. A typical multimeter uses an integrating ADC to convert an unknown voltage –An integrating capacitor is charged for a precise time span, then discharged. –The discharge time is proportionate to the unknown signal charging the integrator. –The longer the integration time, the higher the resolution, therefore more accurate the measurement becomes. Accuracies as low as 10’s of parts per million (0.001 %) can be achieved Time in Seconds Amplitude in Volts

43. What is an Oscilloscope? An Oscilloscope graphically plots signals over time –The oscilloscope using high speed A to D conversion, samples the unknown input as fast as possible then graphically plots the unknown samples over time “A picture is worth a thousand words!” Amplitude in Volts Time in Seconds

44. DMM or Oscilloscope? A multimeter, presents a single precise measured value An oscilloscope presents a graphical representation of a signal change over time. –To obtain precise measurements, the typical DMM converts the unknown input at a rate of 5 or 10 times per second –To accurately represent a signal change over time, an oscilloscope can sample the unknown input up to 2.5 billion times per second (or faster)

45. Digital Storage Oscilloscope Input Coupling AC or DC Amplitude Control Attenuation Amplification Channel Isolation Up to 1000 Volt isolation Available on some scopes A to D Conversion Real time Up to 2.5 GSa/s System Control Sample Storage Measure functions Graphics processing User interface Ch A 2.5 GSa/s A/D Lf Hf Optional Ch Isolation Micro Processor Memory Triggering Edge Edge Delay Pulse Width N-Cycle

46. Input Coupling Input coupling determines what is passed on to the signal conditioning circuit –AC, Passes AC component only –DC, Passes both AC and DC components of the signal Gnd Ref Applied Input Resultant Output DC Coupling AC Coupling AC & DC Signal Components AC Signal Component, DC is blocked by capacitor Gnd Ref

47. Display Amplitude Control Controls the vertical span of the displayed signal, adjusted in volts per vertical display division –mV increases sensitivity –V decreases sensitivity mV V Gnd Ref Vertical Sensitivity (V/Div) Amplitude display range Pressing mV increases vertical sensitivity Pressing V deceases vertical sensitivity

48. Analog to Digital Conversion 1 2 3 4 5 6....... 1000 Horizontal Time base (s/Div) Sampling clock interval time Horizontal resolution mS/Div The unknown signal is applied to the analog to digital converter (A/D). –The A/D process divides the signal into segments at specified time intervals. –At each time interval the voltage of the signal is determined and stored into memory S/Div A to D Conversion Storage Memory Gnd Ref

49. Sample Rate & Memory A digital storage oscilloscope contains a fixed amount of memory points –The more memory, the higher the cost and the longer it takes to fill up over a complete acquisition cycle –The fewer memory points the lower the resolution, the displayed signal time span and frequency bandwidth The sample rate will increase or decrease relative to the amount of memory and maximum sample rate It will automatically adjust the sample rate from its maximum at the fastest time base setting (nano seconds/div) to a slower sample rate at the slower time base settings (example, milli seconds/div) Memory Depth time Cost Sample Rate Time base ns Min S gS

50. Digital Oscilloscope Aliasing If the acquisition rate is much slower than the frequency of the measured signal Aliasing can occur Aliasing displays incorrect signals Actual Signal Signal observed when Aliasing occurs

51. A/D – Glitch Detection Glitch Detect –At slow time base settings/ sampling intervals the A/D can miss glitches –Over sampling captures min and max sample points, preventing aliasing and displaying glitches Digitized Signal Actual Signal Over Sampling Glitch Detect The Min & Max samples displayed in each column Displayed Max Sample Displayed Min Sample Display Pixels

52. Oscilloscope Bandwidth Frequency 1 Frequency 2 Frequency 3 Bandwidth, determines the highest signal frequency the oscilloscope can accurately reproduce –The maximum frequency is usually determined by measuring the point at which the amplitude decreases as frequency increases by no more than -3 db’s (30% change) –Bandwidth is also dependent on sampling rate Test Signal Volume Perceived Volume

53. Triggering Triggering, synchronizes the waveform display process every time the waveform is refreshed or displayed. 1 2 3 4 Composite image of “Un- Triggered” scope T Triggered, resulting in stable display Acquisition cycles

54. Triggering Techniques Oscilloscopes use several techniques to trigger on unknown signals –Edge, a specific voltage level set relative to either a rising or falling edge. –Pulse Width, specifies both a specific voltage level relative to an edge, plus a time interval between the rise and falling edges (or visa versa). –Automatic Connect&View: As implied, connect then view, as simple as that! Eliminates need to continuously adjust the scope vertical sensitivity, horizontal time and trigger settings V level time V/Div Time/Div Trigger

55. Oscilloscope Isolation The ScopeMeter input connectors are insulated to prevent against exposure to electrical voltages The input power adapter is isolated from earth ground, allowing for floating measurements A typical bench oscilloscope uses metal BNC connectors and metal chassis components, potentially exposing the user to hazardous voltages. To protect against electric shock the bench oscilloscope is connected directly to earth ground via wall outlet. Isolated adapter DC Out AC to DC Power Adapter, specially designed to meet CAT II 1000V/ CAT III 600V Safety rating Ref ARef B

56. Channel Isolation Bench oscilloscope with exposed metal BNC connectors and common input references, for safety reasons are tied to earth ground Fluke 190 series portable oscilloscope with insulated BNC input connectors isolated from earth ground with isolated input references CH A Signal Input CH B Signal Input CH A Referen ce Input CH B Referen ce Input CAT II 1000 V/ CAT III 600V Isolation Common reference tied to earth ground CH A Signal Input CH B Signal Input The Fluke ScopeMeter test tools provide a safe means to measure floating differential voltages

57. Using the 190-204 Oscilloscope Input Connections –BNC Connectors are 300V CAT IV –Fluke 10:1 Probes provide 1000V CAT III 600V CAT IV

58. Using the 190-204 Oscilloscope Resetting the 190-204 to factory settings

59. Using the 190-204 Oscilloscope Hiding Labels and Key Illumination meaning

60. Using the 190-204 Oscilloscope Probe Settings

61. Using the 190-204 Oscilloscope Selecting Input Channels

62. Using the 190-204 Oscilloscope Connect-and-View™

63. Using the 190-204 Oscilloscope Automatic Measurements

64. Using the 190-204 Oscilloscope Average, Persistance, and Glitch Capture

65. Using the 190-204 Oscilloscope Displaying Glitches and suppressing High Frequency Noise

66. Using the 190-204 Oscilloscope Acquisition Rate

67. Using the 190-204 Oscilloscope AC/DC Coupling

68. Using the 190-204 Oscilloscope Bandwidth and Noisy Waveforms

69. Using the 190-204 Oscilloscope Mathematics (FFT)

70. Using the 190-204 Oscilloscope Reference Trace

71. Using the 190-204 Oscilloscope Meter Mode

72. Using the 190-204 Oscilloscope Trend Plot Meter

73. Using the 190-204 Oscilloscope ZOOM Button

74. Using the 190-204 Oscilloscope CURSOR Button

75. Using the 190-204 Oscilloscope Record Waveforms in Deep Memory

76. Using the 190-204 Oscilloscope Scope Record in Single Sweep Mode

77. Using the 190-204 Oscilloscope REPLAY Button

78. Using the 190-204 Oscilloscope Trigger Level

79. Using the 190-204 Oscilloscope Saving and Recalling

80. Using the 190-204 Oscilloscope FlukeView Scope Software Demonstration

81. Fluke Support Fluke Website and Support

82. Conclusion Questions?