Embedded Files
LMG641 - Power Analysis²
LMG641 - Power Analysis²
One-shot Results for Narrowband, Full Spectrum and Harmonics
Features:
Measurement Channels
♦ Outstanding accuracy of 0.015% of measured value + 0.01% of range
♦ Full dynamic range of 500 µA to 32 A / 3 mV to 1000 V per channel available in single instrument
♦ Power measurements from standby to full load (max. 32 A) without mechanical changes
♦ Analog bandwidth DC up to 10 MHz
♦ Modular configuration with 1 to 4 power measurement channels (alternatively 3 channels + 1 I/O card)
♦ Gapless sampling up to 18 bit and a cycle time of 30 ms
♦ Delay time between V and I input < 3ns, very precise measurements at small power factors (PF) and/or high frequencies
Features
♦ Simultaneous measurement of narrow- and broadband values through innovative DualPath architecture
♦ Simultaneous capturing of fundamental frequency and broadband RMS values for instantaneous detection of losses, resp. high-frequency components
♦ Harmonics and interharmonics up to 2000. order, as required by EN61000-4-7
♦ With optional I/O card speed/torque inputs freely configurable for all signal types (analogue, frequency as RS422,TTL or HTL) via menu
♦ Flexible scripting tool for custom applications
♦ Simultaneous measurement of V, I, P values and harmonics, presentation in tabular or graphical form
♦ Signal filters freely configurable by frequency, type and characteristics
♦ Synchronization to up to 4 different frequencies simultaneously
♦ Flicker measurement, interactions between grid and appliance according to EN61000-4-15
User-Interface
♦ Large and clearly arranged touchscreen GUI for intuitive handling
♦ All instrument features displayed, identical look-and-feel for local and remote operation for quick and easy familiarization
Memory and Interfaces
♦ Internal storage of long-term measurements even with shortest cycle-time thanks to integrated mass storage device
♦ Excellent connectivity via USB3.0, Gbit-LAN, RS-232 and DVI
Miscellaneous
♦ Convenient "plug-and-measure" through automated sensor detection
♦ no external sensor power supply required
♦ 12 months guaranteed calibration interval for minimal service cost and optimal availability
♦ Calibration certificate included free-of-charge in first delivery
♦ 24 months warranty
Features
Features
Flexibility
Synchronization
Synchronize simultaneously on up to seven different frequencies
DualPath
Simultaneous measurement in two bandwidths thanks DualPath - no compromises, no doubt
In Power meters of traditional construction, a signal first passes through an analog processing, the output values are digitized by an A / D converter and then processed. The resulting signal may then either measured over the full range, or treated with anti-aliasing filters, e.g., to serve as the basis for an FFT or other digital filtering. By restriction to an A / D converter, one has to taken certain disadvantages into account. If measured with a filter, in order to avoid aliasing in the FFT, the broadband values are lost. When the filter is disengaged, strictly speaking, the FFT has to be omitted. If the FFT is performed without anti-aliasing filter for measurement over the full bandwidth, the quality of the calculated values is questionable. For example, an aliasing error of 50% would of course be easily detected, a deviation of 0.5% could remain unnoticed. Finally, it can be switched back and forth between measurements with and without filters. The validity of these results is, however, also doubtful, as would be expected of a temporal invariability of the signal, which is hardly ever the case in reality. Moreover, this method is extremely time consuming.
Ultimately, the shown measurement methods are unsatisfactory compromises. For this reason, ZES ZIMMER has radically redesigned the signal conditioning and developed the DualPath architecture. The analog side corresponds to the conventional instruments, the subsequent digital processing, however, was revolutionized. The power analyzers of the LMG600 Series are the first power meters featuring two A / D converters in each of the two independent signal paths for current and voltage channel. A filter for the contact measurement of the broadband signal, and another for the narrowband signal at the output of anti-aliasing filter. By means of parallel processing of the digitized samples, the user has access to both measurements of the same signal without the risk of aliasing. This unique process eliminates all the disadvantages of previous approaches and guarantees accurate results in the shortest time.
A/B/C/S-Channels
For every application the right channel type:
S-Channel:0.025 % accuracy, up to 10 MHz, DC-optimized, up to 1000 VAC/1500 VDC
A-Channel: 0.025 % accuracy, up to 10 MHz, up to 1000 VAC
B-Channel: 0.07 % accuracy, up to 500 kHz, up to 100 0VAC
C-Channel: 0.04 % accuracy, up to 10 kHz, up to 1000 VAC
Plug ’n’ Measure
Custom Menu
The GUI you always wanted…
… in less than 20 minutes
Display only what you really need in a way that helps you most to achieve the task at hand - as easy as 1-2-3:
Arrange all relevant results on a single screen
Mix graphical and numerical data to compose meaningful views
Combine results from different channels and groups
Enrich measured data with derived values
Add your individual corporate touch by the use of logos and other graphical elements
Interfaces
Star-Delta
Conversion from phase to phase in the phase voltages and determination of the active power
For a 3-phase 3-wire system only the phase voltages U12, U23, U31 and the phase currents I1, I2, I3 are amenable to measurement. With the help of star-delta conversionline, voltages can be determined in the inaccessible phase voltages, converted into the associated active powers. In analogy, the phase currents can be converted into the "chained" currents. From the values thus calculated, all other variables, e.g. harmonics, are derived. Distortions and asymmetries of power and consumers are considered correctly. The use of an external artificial neutral point is thus superfluous, but such can be connected, if required, at any time, in case the associated disadvantages (e.g. increased power dissipation) are accepted.
Calibration
12 months guaranteed calibration for low maintenance cost and optimum equipment availability
Free calibration protocol included at first delivery
Warranty
All ZES ZIMMER power meters of the LMG series, the current sensors of PCT series and the voltage sensors of the HST series are carefully tested, adjusted and calibrated prior to shipment and are subject to strict quality controls.
ZES ZIMMER guarantees for a period of 24 months from first delivery that these products are free from defects in material or workmanship.
Harmonics
Harmonics and inter-harmonics up to the 1000th order in the GUI and up to the 2000th order via the innterface, in accordance with standards as per EN61000-4-7
Process signals
Process Signal Interface (PSI)
(optional) speed / torque sensor inputs via the menu on all signal types
freely configurable (analog, frequency and RS422, TTL or HTL)
Flexible Filter
Signal filter freely adjustable according to frequency, type and characteristics
Remote control
LMG Remote
The LMG Remote PC software allows to easily control the LMG671 remotely from a Windows PC. Since this software mimicks the measuring device itself down to the last detail, the LMG671 can be operated as usual, even from the PC - no rethinking required, no familiarization time.
Continuity
Complete data collection
In the wake of stricter monitoring of consumption and efficiency of electrical appliances, new standards and procedures (eg SPECpower_ssj2008, IEC 62301) will continuously be created to enable an objective comparison of the different manufacturers. Whether it is workstations, servers or appliances, is irrelevant to the principle: The long-term evaluation of the power consumption has always to take all relevant operating conditions into account. The differences between minimum load - e.g., Idle mode, - and full load can thereby be of considerable magnitude, which requires a very sophisticated means of measurement (see also Application Note No. 102, "Measurement of standby power and energy efficiency."). The measurements must be carried out over several hours and may not show any gaps. By selecting a sufficiently large measurement range, range changes and the inevitably resulting data losses can be avoided. The fundamental precision LMG600 also ensures an accurate measurement at the lower limit of a range.
Exact signal transit time
Exact measurements thanks to minimal runtime differences
The fast switching semiconductors used to improve the efficiency of modern frequency converters cause extremely steep voltage edges. The resulting capacitive currents affect the bearings and the motor insulation - this can lead to premature failure.
Motor filter (e.g. du / dt filter) attenuate the voltage gradient, but generate themselves power dissipation due to the settling of the filters' frequencies (typically > 100 kHz). The high bandwidth and the small time difference between the current and voltage of the LMG600 enable highly accurate power loss measurements on the filters at these frequencies, and longitudinal measurements with small cos φ. This also applies to power measurements at high bandwidths up to 10 MHz. This requires that the current and voltage channels must be designed for minimum delay differences; in the LMG600 it is less than 3 ns; this corresponds to 50 Hz at an angle error <1 μrad. The instrument is therefore ideally suited for the power loss measurement at small phase angles for transformers, inductors, capacitors and ultrasonic sensors. No options or adjustments are necessary, as the devices will fully meet this measurement task already in the default setting when shipped. For measurements on circuits of highest performance, typically current and voltage transducers are employed. The phase angle of the converter can be corrected via the runtime menu and thus the measurement accuracy can be improved.
Page updated
Google Sites
Report abuse