Patent US6112159A successfully refreshed from Google Patents.
US6112159A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Robust electrical utility meter
Assignee: Landis and Gyr LLC
•
Filing: 1997-06-24
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Granted: 2000-08-29
•
Expires: 2017-06-24
Abstract
Abstract The present invention includes an electrical utility meter operable to measure power consumption. The method detects and compensates for one or more wiring errors that affects the power consumption measurement of the electrical utility meter. The method includes the steps of: obtaining measured phase angle data for a plurality of phases in a polyphase electrical system; periodically performing one or more diagnostic tests using the measured phase angle data to determine whether a wiring error is present, automatically adjusting the operation of the electrical utility meter to effect a compensation for the wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter. The meter is operable to detect and compensate for wiring errors including polarity errors and cross phasing errors. According to another method of the present invention, the meter is operable to determine automatically the service type to which it is connected.
Inventors
- 👤 Randall K. Bond
- 👤 Gordon G. Burns
- 👤 Robert E. Slaven
- 👤 Christopher L. Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:36
CPC Classifications
G; G01; G01R; G01R21/00; G01R21/133; G01R21/1333; G01R22/00; G01R31/00; G01R31/50; G01R31/66; G06; G06Q; G06Q50/00; G06Q50/06
Claims Analysis
Total Claims: 64
Claim 1
Independent Claim
109 words
In an electrical utility meter, the electrical utility meter operable to measure power consumption, a method of detecting and compensating for a wiring error that affects the power consumption measurement of the electrical utility meter, the method comprising: a) obtaining measured phase angle data for a plurality of phases in a polyphase electrical system; b) periodically performing one or more diagnostic tests using the measured phase angle data to determine whether a wiring error is present; and c) automatically adjusting the operation of the electrical utility meter to effect a compensation for the wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter.
Claim 2
Dependent Claim
109 words
In an electrical utility meter, the electrical utility meter operable to measure power consumption, a method of detecting and compensating for a wiring error that affects the power consumption measurement of the electrical utility meter, the method comprising: a) obtaining measured phase angle data for a plurality of phases in a polyphase electrical system; b) periodically performing one or more diagnostic tests using the measured phase angle data to determine whether a wiring error is present; and c) automatically adjusting the operation of the electrical utility meter to effect a compensation for the wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter.
Claim 3
Dependent Claim
83 words
The method of claim 1 wherein step a) further comprises obtaining measured voltage phase angle data, wherein step b) further comprises periodically performing one or more diagnostic tests using the measured voltage phase angle data to determine whether a voltage polarity error is present, said voltage polarity error comprising at least one phase voltage being approximately 180° out of phase, and wherein step c) further comprises automatically adjusting the operation of the utility meter by effecting a compensation for the voltage polarity error.
Claim 4
Dependent Claim
80 words
The method of claim 1 wherein step a) further comprises obtaining measured current phase angle data and measured voltage phase angle data, wherein step b) further comprises periodically performing one or more diagnostic tests using the measured voltage phase angle data and measured current phase angle data to determine whether a cross phase error is present, and wherein step c) further comprises automatically adjusting the operation of the electrical utility meter to effect a compensation for the cross phase error.
Claim 5
Dependent Claim
68 words
The method of claim 1 wherein step a) further comprises obtaining measured current phase angle data, wherein step b) further comprises periodically performing one or more diagnostic tests using the measured current phase angle data to determine whether a current polarity error is present, and wherein step c) further comprises automatically adjusting the operation of the electrical utility meter to effect a compensation for the current polarity error.
Claim 6
Dependent Claim
107 words
The method of claim 1 wherein step a) further comprises obtaining measured voltage magnitude and phase angle data and measured current magnitude and phase angle data, step b) further comprises periodically performing one or more diagnostic tests using the measured voltage magnitude and phase angle data and the measured current phase angle data to determine whether one of a plurality of wiring errors is present and further identifying the wiring error from the plurality of wiring errors if a wiring error is present, and wherein step c) further comprises automatically adjusting the operation of the electrical utility meter to effect a compensation for the identified wiring error.
Claim 7
Dependent Claim
66 words
The method of claim 1 wherein step a) further includes obtaining measured voltage magnitude data, step b) further comprises periodically performing one or more diagnostic tests using the measured voltage magnitude data to determine whether a missing voltage error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the missing voltage error.
Claim 8
Dependent Claim
37 words
The method of claim 1 wherein the controller is further operable to periodically perform one or more diagnostic tests by obtaining expected values from a memory and comparing the measured phase angle data to the expected values.
Claim 9
Dependent Claim
29 words
The method of claim 1 further comprising a step d) of determining a present service type corresponding to the polyphase electrical system from a plurality of possible service types.
Claim 10
Dependent Claim
69 words
The method of claim 7 wherein step a) further comprises obtaining measured voltage magnitude data, and wherein the method further comprises: d) obtaining the expected values for one or more of the plurality of possible service types from the memory; and e) comparing the expected values for one or more of the plurality of possible service types to the measured voltage magnitude data and the measured phase angle data.
Claim 11
Dependent Claim
94 words
The method of claim 1 wherein step a) further comprises: receiving voltage and current measurement signals for a plurality of phases in a polyphase electrical system; employing an analog to digital converter to generate digital measurement signals using said voltage and current measurement signal, said digital measurement signals including digital voltage measurement signals and digital current measurement signals for each phase of the polyphase electrical system, and generating measured data using the digital measurement signals, said measured data comprising measured voltage magnitude and phase angle data and measured current magnitude and phase angle data.
Claim 12
Dependent Claim
50 words
The method of claim 10 wherein the digital measurement signals each comprise a sampled waveform including one or more samples, and wherein step a) further comprises generating watts data by multiplying digital voltage measurement signal samples by digital current measurement signal samples for each phase of the polyphase electrical system.
Claim 13
Dependent Claim
32 words
The method of claim 1 wherein step a) further comprises generating measured voltage magnitude data by performing a root-mean-square calculation on a plurality of digital voltage measurement signal samples for each phase.
Claim 14
Dependent Claim
32 words
The method of claim 11 wherein step a) further comprises generating measured current magnitude data by performing a root-mean-square calculation on a plurality of digital current measurement signal samples for each phase.
Claim 15
Dependent Claim
36 words
The method of claim 11 wherein step a) further comprises generating measured voltage phase angle data using the zero crossings of the digital voltage measurement signals for the plurality of phases in the polyphase electrical system.
Claim 16
Dependent Claim
69 words
The method of claim 11 wherein step b) further comprises periodically performing one or more diagnostic tests using the measured data to determine whether a voltage polarity error is present, said voltage polarity error comprising at least one phase voltage being approximately 180° out of phase, and wherein controller is further operable to adjust the operation of the utility meter by effecting a compensation for the voltage polarity error.
Claim 17
Dependent Claim
45 words
The method of claim 15 wherein step c) further comprises effecting the compensation for the voltage polarity error by causing the digital signal processor to multiply the digital voltage measurement signal samples corresponding to at least one phase of the polyphase electrical system by -1.
Claim 18
Dependent Claim
100 words
The method of claim 11 wherein step b) further comprises performing one or more diagnostic tests using the measured data to determine whether a cross phase error is present, said cross phase error comprising a digital current measurement signal for a first phase to correspond to a second phase of the polyphase electrical system, and a digital current measurement signal for the second phase to correspond to a first phase of the polyphase electrical system, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the cross phase error.
Claim 19
Dependent Claim
75 words
The method of claim 17 wherein step c) further comprises effecting the compensation for the cross phase error by causing the digital signal processor to generate watts data by multiplying the digital current measurement signal samples of the first phase by the digital voltage measurement signal samples of the second phase and by multiplying the digital voltage measurement signal samples of the first phase by the digital current measurement signal samples of the second phase.
Claim 20
Dependent Claim
54 words
The method of claim 11 wherein step b) further comprises performing one or more diagnostic tests using the measured data to determine whether a current polarity error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the current polarity error.
Claim 21
Dependent Claim
45 words
The method of claim 19 wherein step c) further comprises effecting the compensation for the current polarity error by causing the digital signal processor to multiply the current voltage measurement signal samples corresponding to at least one phase of the polyphase electrical system by -1.
Claim 22
Dependent Claim
138 words
In an electrical utility meter, the electrical utility meter operable to measure power consumption, a method of detecting and identifying a wiring error that affects the power consumption measurement of the electrical utility meter, the method comprising: a) obtaining measured data for a plurality of phases in a polyphase electrical system, said measured data comprising measured voltage magnitude and phase angle data and measured current magnitude and phase angle data; b) automatically identifying the present electrical service type based on the measured voltage magnitude and phase angle data; and c) periodically performing one or more diagnostic tests using at least a portion of the measured data and the present electrical service type to determine whether a wiring error is present and to identify the wiring error from a plurality of wiring errors if a wiring error is detected.
Claim 23
Dependent Claim
138 words
In an electrical utility meter, the electrical utility meter operable to measure power consumption, a method of detecting and identifying a wiring error that affects the power consumption measurement of the electrical utility meter, the method comprising: a) obtaining measured data for a plurality of phases in a polyphase electrical system, said measured data comprising measured voltage magnitude and phase angle data and measured current magnitude and phase angle data; b) automatically identifying the present electrical service type based on the measured voltage magnitude and phase angle data; and c) periodically performing one or more diagnostic tests using at least a portion of the measured data and the present electrical service type to determine whether a wiring error is present and to identify the wiring error from a plurality of wiring errors if a wiring error is detected.
Claim 24
Dependent Claim
42 words
The method of claim 21 further comprising a step: d) automatically adjusting the operation of the electrical utility meter to effect a compensation for the identified wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter.
Claim 25
Dependent Claim
26 words
The method of claim 21 further comprising a step: d) displaying information on a meter display that provides an indication corresponding to the identified wiring error.
Claim 26
Dependent Claim
152 words
An arrangement for use in an electrical utility meter, the electrical utility meter operable to be connected to one or more electrical service types, the arrangement operable to detect and compensate for a wiring error, the arrangement comprising: a) a conversion circuit for generating a power consumption measurement and for generating measured phase angle data for a plurality of phases in a polyphase electrical system; b) a memory; and c) a controller operably connected to said memory and said conversion circuit, the processor operable to receive measured phase angle data for a plurality of phases in a polyphase electrical system, periodically perform one or more diagnostic tests using the measured phase angle data to determine whether a wiring error is present, and automatically adjust the operation of the conversion circuit to effect a compensation for the wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter.
Claim 27
Dependent Claim
152 words
An arrangement for use in an electrical utility meter, the electrical utility meter operable to be connected to one or more electrical service types, the arrangement operable to detect and compensate for a wiring error, the arrangement comprising: a) a conversion circuit for generating a power consumption measurement and for generating measured phase angle data for a plurality of phases in a polyphase electrical system; b) a memory; and c) a controller operably connected to said memory and said conversion circuit, the processor operable to receive measured phase angle data for a plurality of phases in a polyphase electrical system, periodically perform one or more diagnostic tests using the measured phase angle data to determine whether a wiring error is present, and automatically adjust the operation of the conversion circuit to effect a compensation for the wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter.
Claim 28
Dependent Claim
46 words
The arrangement of claim 24 wherein said polyphase electrical system includes a plurality of phase voltages and a plurality of phase currents, and wherein the conversion circuit is operable to generate measured phase angle data using zero crossings of each of the plurality of phase voltages.
Claim 29
Dependent Claim
56 words
The arrangement of claim 24 wherein said polyphase electrical system includes a plurality of phase voltages and a plurality of phase currents, and wherein the conversion circuit is operable to generate watts data and VAR data, and wherein the measurement circuit is operable to generate measured phase angle data using the watts data and VAR data.
Claim 30
Dependent Claim
73 words
The arrangement of claim 24 wherein the controller is further operable to periodically performing one or more diagnostic tests using the measured phase angle data to determine whether a voltage polarity error is present, said voltage polarity error comprising at least one phase voltage being approximately 180° out of phase, and wherein controller is further operable to adjust the operation of the utility meter by effecting a compensation for the voltage polarity error.
Claim 31
Dependent Claim
58 words
The arrangement of claim 24 wherein the controller is further operable to perform one or more diagnostic tests using the measured phase angle data to determine whether a cross phase error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the cross phase error.
Claim 32
Dependent Claim
58 words
The arrangement of claim 24 wherein the controller is further operable to perform one or more diagnostic tests using the measured phase angle data to determine whether a current polarity error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the current polarity error.
Claim 33
Dependent Claim
35 words
The arrangement of claim 24 wherein the conversion circuit is further operable to generate measured phase voltage magnitude data and measured phase current magnitude data for a plurality of phases in a polyphase electrical system.
Claim 34
Dependent Claim
125 words
The arrangement of claim 30 wherein the conversion circuit is further operable to obtain measured voltage magnitude and phase angle data and measured current magnitude and phase angle data, and wherein the controller is further operable to receive the measured voltage magnitude and phase angle data and measured current magnitude and phase angle data, periodically perform one or more diagnostic tests using the measured voltage magnitude and phase angle data and the measured current magnitude and phase angle data to determine whether one of a plurality of wiring errors is present, identify the wiring error from the plurality of wiring errors if a wiring error is present, and adjust the operation of the electrical utility meter to effect a compensation for the identified wiring error.
Claim 35
Dependent Claim
166 words
An arrangement for use in an electrical utility meter, the electrical utility meter operable to be connected to one or more electrical service types, the arrangement operable to detect and compensate for a wiring error, the arrangement comprising: a) a conversion circuit for generating a power consumption measurement and for generating measured data, said measured data including measured voltage magnitude and phase angle data and measured current magnitude and phase angle data for a plurality of phases in a polyphase electrical system; b) a memory; and c) a controller operably connected to said memory and said conversion circuit, the processor operable to receive said measured data for a plurality of phases in a polyphase electrical system, periodically perform one or more diagnostic tests using the measured data to determine whether a wiring error is present, and automatically adjust the operation of the conversion circuit to effect a compensation for the wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter.
Claim 36
Dependent Claim
166 words
An arrangement for use in an electrical utility meter, the electrical utility meter operable to be connected to one or more electrical service types, the arrangement operable to detect and compensate for a wiring error, the arrangement comprising: a) a conversion circuit for generating a power consumption measurement and for generating measured data, said measured data including measured voltage magnitude and phase angle data and measured current magnitude and phase angle data for a plurality of phases in a polyphase electrical system; b) a memory; and c) a controller operably connected to said memory and said conversion circuit, the processor operable to receive said measured data for a plurality of phases in a polyphase electrical system, periodically perform one or more diagnostic tests using the measured data to determine whether a wiring error is present, and automatically adjust the operation of the conversion circuit to effect a compensation for the wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter.
Claim 37
Dependent Claim
71 words
The arrangement of claim 32 wherein the controller is further operable to periodically performing one or more diagnostic tests using the measured data to determine whether a voltage polarity error is present, said voltage polarity error comprising at least one phase voltage being approximately 180° out of phase, and wherein controller is further operable to adjust the operation of the utility meter by effecting a compensation for the voltage polarity error.
Claim 38
Dependent Claim
56 words
The arrangement of claim 32 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a cross phase error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the cross phase error.
Claim 39
Dependent Claim
56 words
The arrangement of claim 32 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a current polarity error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the current polarity error.
Claim 40
Dependent Claim
56 words
The arrangement of claim 32 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a missing voltage error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the missing voltage error.
Claim 41
Dependent Claim
35 words
The arrangement of claim 32 wherein the controller is further operable to periodically perform one or more diagnostic tests by obtaining expected values from the memory and comparing the measured data to the expected values.
Claim 42
Dependent Claim
29 words
The arrangement of claim 32 wherein the controller is further operable to determine a service type corresponding to the polyphase electrical system from a plurality of possible service types.
Claim 43
Dependent Claim
75 words
The arrangement of claim 38 wherein the memory contains expected values corresponding to the plurality of possible service types and the controller is further operable to determine the service type corresponding to the polyphase electrical system by obtaining the expected values for one or more of the plurality of possible service types from the memory and comparing the expected values for one or more of the plurality of possible service types to the measured data.
Claim 44
Dependent Claim
83 words
The arrangement of claim 32 wherein the conversion circuit includes at least one analog to digital ("A/D") converter operable to receive voltage and current measurement signals for a plurality of phases in a polyphase electrical system and generate digital measurement signals, said digital measurement signals including digital voltage measurement signals and digital current measurement signals for each phase of the polyphase electrical system, and wherein the conversion circuit further includes means for receiving the digital measurement signals and generating the measured data therefrom.
Claim 45
Dependent Claim
44 words
The arrangement of claim 40 wherein the digital measurement signals each comprise a sampled waveform including one or more samples, and wherein the conversion circuit generates watts data by multiplying digital voltage measurement signal samples by digital current measurement signal samples for each phase.
Claim 46
Dependent Claim
42 words
The arrangement of claim 41 wherein the means for receiving digital measurement signals and generating measured data is operable to generate measured voltage magnitude data by performing a root-mean-square calculation on a plurality of digital voltage measurement signal samples for each phase.
Claim 47
Dependent Claim
42 words
The arrangement of claim 42 wherein the means for receiving digital measurement signals and generating measured data is operable to generate measured current magnitude data by performing a root-mean-square calculation on a plurality of digital current measurement signal samples for each phase.
Claim 48
Dependent Claim
46 words
The arrangement of claim 41 wherein the means for receiving digital measurement signals and generating measured data is operable to generate measured voltage phase angle data using the zero crossings of the digital voltage measurement signals for the plurality of phases in the polyphase electrical system.
Claim 49
Dependent Claim
71 words
The arrangement of claim 41 wherein the controller is further operable to periodically performing one or more diagnostic tests using the measured data to determine whether a voltage polarity error is present, said voltage polarity error comprising at least one phase voltage being approximately 180° out of phase, and wherein controller is further operable to adjust the operation of the utility meter by effecting a compensation for the voltage polarity error.
Claim 50
Dependent Claim
53 words
The arrangement of claim 45 wherein the controller is operable to effect the compensation for the voltage polarity error by causing the means for receiving digital measurement signals and generating measured data to multiply the digital voltage measurement signal samples corresponding to at least one phase of the polyphase electrical system by -1.
Claim 51
Dependent Claim
102 words
The arrangement of claim 41 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a cross phase error is present, said cross phase error comprising a digital current measurement signal for a first phase to correspond to a second phase of the polyphase electrical system, and a digital current measurement signal for the second phase to correspond to a first phase of the polyphase electrical system, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the cross phase error.
Claim 52
Dependent Claim
84 words
The arrangement of claim 47 wherein the controller is further operable to effect the compensation for the cross phase error by causing the means for receiving digital measurement signals and generating measured data to generate watts data by multiplying the digital current measurement signal samples of the first phase by the digital voltage measurement signal samples of the second phase and by multiplying the digital voltage measurement signal samples of the first phase by the digital current measurement signal samples of the second phase.
Claim 53
Dependent Claim
56 words
The arrangement of claim 41 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a current polarity error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the current polarity error.
Claim 54
Dependent Claim
53 words
The arrangement of claim 49 wherein the controller is operable to effect the compensation for the current polarity error by causing the means for receiving digital measurement signals and generating measured data to multiply the current voltage measurement signal samples corresponding to at least one phase of the polyphase electrical system by -1.
Claim 55
Dependent Claim
56 words
The arrangement of claim 41 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a missing voltage error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the missing voltage error.
Claim 56
Dependent Claim
166 words
An arrangement for use in an electrical utility meter, the electrical utility meter operable to be connected to one or more electrical service types, the arrangement comprising: a) a conversion circuit for generating a power consumption measurement and for generating measured data, said measured data including voltage magnitude and phase angle data and current magnitude and phase angle data for a plurality of phases in a polyphase electrical system; b) a memory; and c) a controller operably connected to said memory and said conversion circuit, the processor operable to receive measured data for a plurality of phases in a polyphase electrical system, identify a present electrical service type based on the measured voltage magnitude and phase angle data; and perform one or more diagnostic tests using at least a portion of the measured data and the present electrical service type to determine whether a wiring error is present and to identify the wiring error from a plurality of wiring errors if a wiring error is detected.
Claim 57
Dependent Claim
166 words
An arrangement for use in an electrical utility meter, the electrical utility meter operable to be connected to one or more electrical service types, the arrangement comprising: a) a conversion circuit for generating a power consumption measurement and for generating measured data, said measured data including voltage magnitude and phase angle data and current magnitude and phase angle data for a plurality of phases in a polyphase electrical system; b) a memory; and c) a controller operably connected to said memory and said conversion circuit, the processor operable to receive measured data for a plurality of phases in a polyphase electrical system, identify a present electrical service type based on the measured voltage magnitude and phase angle data; and perform one or more diagnostic tests using at least a portion of the measured data and the present electrical service type to determine whether a wiring error is present and to identify the wiring error from a plurality of wiring errors if a wiring error is detected.
Claim 58
Dependent Claim
44 words
The arrangement of claim 52 wherein the controller is further operable to: automatically adjust the operation of the electrical utility meter to effect a compensation for the identified wiring error, said compensation increasing an accuracy of power consumption measurement of the electrical utility meter.
Claim 59
Dependent Claim
26 words
The arrangement of claim 52 further comprising a display connected to the controller for displaying information that provides an indication corresponding to the identified wiring error.
Claim 60
Dependent Claim
71 words
The arrangement of claim 52 wherein the controller is further operable to periodically performing one or more diagnostic tests using the measured data to determine whether a voltage polarity error is present, said voltage polarity error comprising at least one phase voltage being approximately 180° out of phase, and wherein controller is further operable to adjust the operation of the utility meter by effecting a compensation for the voltage polarity error.
Claim 61
Dependent Claim
56 words
The arrangement of claim 52 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a cross phase error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the cross phase error.
Claim 62
Dependent Claim
56 words
The arrangement of claim 52 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a current polarity error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the current polarity error.
Claim 63
Dependent Claim
56 words
The arrangement of claim 52 wherein the controller is further operable to perform one or more diagnostic tests using the measured data to determine whether a missing voltage error is present, and wherein the controller is further operable to adjust the operation of the electrical utility meter to effect a compensation for the missing voltage error.
Claim 64
Dependent Claim
35 words
The arrangement of claim 52 wherein the controller is further operable to periodically perform one or more diagnostic tests by obtaining expected values from the memory and comparing the measured data to the expected values.
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