Lille og handy “Table-Top” udgave af den populære LMG 600 serie.
Til præcision power måling på elektromotorer, transformere, frekvensomformere, halvledere, belysningselektronik, power supply, power electronics, EMC test mv. DualPath design for måling i power elektronik med høj frekvent indhold, for samtidig display af hele power spektrum og specifikt udvalgt spektrum. Stort udvalg i plug in sensorer med automatisk sensor genkendelse. Ingen ekstern sensor power supply.
* 1 målekanal for spænding og strøm (Galvanisk adskilt).
* Båndbredde DC – 10 MHz med målekanal A1.
* Gapless sampling op til 18 bit og cycle time <30 ms.
* Delay time mellem V og I indgang <3 ns, meget præcise målinger ved lille power faktor (PF) og/eller høje frekvenser.
* Dual Path Sampling med 1,2 MS/s og 150 kS/s.
* Nøjagtighed 0,01% + 0,02% af måleområdet med målekanal A1.
* Strømmåleområder 500 µA til 32 A.
* Spændingsmåleområder 3 mV til 1000 V.
* Med option I/O kort speed/drejningsmoment indgang, fri konfigurérbar for alle signaler (analog, frekvens som RS422, TTL eller HTL) via menu.
* Samtidig måling af V, I, P og harmoniske, vist numerisk i tabelform eller som grafiske kurver.
* Samtidig måling af narrow- og broadband værdier, med DualPath konstruktion.
* Samtidig capturing af fundamental frekvens og broadband RMS værdier for øjeblik detection af tab.
* Harmonisk og interharmonisk op til 400th og 2000th, iht. EN61000-4-7. af U, I, P, Q og S
* Signal filter, fri konfigurérbar frekvens, type og karakteristik. Synkronisering af op til 7 forskellige frekvenser samtidig.
* Flikker måling, interaction mellem grid og appliance iht. EN61000-4-15.
* Hukommelse og interface. Intern hukommelse for langtidsmålinger. USB3.0, Gbit-LAN, RS-232 og DVI / VGA.
* Touch skærm. 8,9″ WSVGA 1024 x 600.
* Remote control PC software.
* Dimensioner (B x H x D) 433 x 177 x 200 mm. Vægt 7,2 kg.
LMG611-A, 1-kanal power analysator, DualPath funktion, touch skærm, Gigabit-Ethernet, USB-A 3.0 (for data storage og perifere enheder), RS232 interface, scope og plot funktion, intern hukommelse for datalogning
Ring tlf. 75522020 eller send en mail info@blichfeld.dk
DualPath
In conventional power analyzers, a signal first undergoes analog conditioning. Then the output is optionally fed through an antialiasing filter (AAF) before it gets digitized by an A/D converter and awaits further processing. The decision for or against the AAF has to be taken before sampling, as this is when aliasing occurs. It cannot be undone later on. RMS values can be determined without risk of aliasing due to their statistical nature, all other measurements need to be handled with care. Due to the limitation to a single A/D converter, there are inherently some downsides to be factored in with conventional devices.
If the goal is to measure RMS power both over the entire bandwidth and at the fundamental frequency, unfiltered and filtered measurements could be alternated – in theory. In practice, it is of utmost difficulty to exactly reproduce the same operating point twice. Unless this can be guaranteed, all comparisons between results are void due to lack of repeatability. Besides, this procedure is extremely time-consuming. If one variant is skipped in order to save time, the results are inevitably error-prone. If the filter remains activated to avoid aliasing with the FFT, bandwidth gets sacrificed when measuring RMS values. Switching off the AAF voids the FFT. If it is carried out nevertheless, the quality of the results is questionable. An aliasing error of 50%, for instance, is easily detected, however a deviation of 0.5% could go unnoticed.
In the end, all of the aforementioned measurement methods are merely unsatisfactory compromises. This is why ZES ZIMMER has fundamentally redesigned signal processing and developed the DualPath architecture. The analog side is the same as in conventional measuring devices, however the subsequent digital processing has been revolutionized. Only power analyzers of the LMG600 series are equipped with two A/D converters in two independent signal paths for each current and voltage channel. One, for the filterless measurement of the wideband signal, and another, for the narrowband signal at the output of the antialiasing filter.
The parallel processing of the digitized sample values gives the user access to both measurements of the same signal, without risking aliasing effects. This unique procedure avoids all of the downsides of previous approaches and guarantees the most precise result in the shortest time possible.
The instruments of manufacturer Y are sampling with all filters removed, and allow you to apply digital filtering later on in order to isolate narrowband values – does this not achieve the same results as DualPath? No, it merely proves the Nyquist-Shannon theorem and the subject of aliasing have not been properly grasped. Frequency portions for whom the sampling rate is insufficient according to the theorem need to be removed prior to filtering, as they can no longer be identified after sampling. E.g. a signal at 50 Hz below the sampling rate would show up at 50 Hz after sampling. This signal, which has been created by undersampling, is indistinguishable from the original signal, since part of the original information has been wiped out due to the insufficient sampling rate.
ZES ZIMMER DualPath Frequency exampleThe green line represents a high-frequency (2 MHz) signal before sampling, the red dots show the result of undersampling – here with a rate slightly higher than the signal frequency (2.125 MHz). The erroneous sampling process, since too slow according to the Nyquist-Shannon theorem, creates a “phantom signal” at a frequency of (2.125 MHz – 2 MHz = 125 kHz), which is merely 1/16 of the original frequency and can no longer be distinguished from the genuine signal content around 125 kHz.
In that range, e.g. harmonics of a frequency converter’s switching frequency might appear, which would in turn be distorted by the “phantom signal”. The knowledge that part of the power measured around 125 kHz stems from the undersampled 2 MHz signal is irretrievably lost. The above values are merely examples, the erroneous frequency components might as well appear near the fundamental of the unit under test. Trying to identify these components after the fact and to remove them would be as futile as striving to identify blue objects on a color photography reduced to black and white – the information “color“ is irretrievably lost, the remaining information “brightness“ is by no means equivalent.
ZES ZIMMER Current Sensors, Clamps and Transformers
Den seneste Firmware er tilgængelig på forespørgsel.
ChangeLog fil kan sendes på forespørgsel.
Nyeste Softwareversion : Firmware version 3.123
Tidligere versioner:
New features:
– Test Suite: New pre-test to evaluate THC for IEC 61000-3-2 [RM#4359]
– LMG-Control: Multiple Versions can be installed in parallel [RM#5056]
New features:
– Test Suite: Add support for split-phase (Single-Phase 3-Wire) systems in standby tests [RM#4953]
– Script Editor: Possibility to start energy measurement on individual groups [RM#4305]
New features:
– Initial support for S2 power channels [RM#3008]
– Direct download of manual in help system [RM#4036]
– Test Suite: Improvement of the formatting of raw values in test report [RM#4095]
– Test Suite: Add support for RI 2415 [RM#2956]
– Test Suite: Added preview of IEC 61000-3-16 (1108/CD) [RM#2552]
– Test Suite: Allow saving to network drives [RM#3040]
– LMG-Control: Windows-Installer is now signed [RM#2395]
– SampleVision: add linear-y scaling option to spectrum [RM#2475]
Firmware version 3.051
New features:
– GUI: Validation of sufficient CAN-bus transmit bandwidth by softkey. [RM#2423]
– Test Suite: Add sampling-interval to the report for standby measurements. [RM#2300]
– Sample Vision: Prevent accidental gaps in recording. [RM#2332]
CAN bus som kommunikationssystem spiller en dominerende rolle i bl.a. automobilbranchen og vil fortsat være en afgørende faktor i fremtiden. Med stadigt voksende udvikling og innovation indenfor elektriske drev, stiger kravende til både dybdeanalyse og levering af data fra Power Analyzeren via CAN bus.
ZES ZIMMERs LMG600 serie, var den første Power Analyzer med Bi-Directional CAN Interface med op til 128 målte værdier på bussen. Fra og med “firmware version 3.021”, nu op til 256 – dvs. dobbelt så mange målte værdier kan nu blive sendt. Brugeren konfigurerer en CAN besked med op til 2 målte værdier så belastningen af CAN bussen ikke øges men effektiviteten af datatransmissionen øges. Dette er især en hjælp ved Multi-phase applikationer og ved transmission af mange udlæsninger, såsom: broadband current, voltage, power values, individual harmonics – men også motorrelevante udlæsninger, som: speed, torque, d-axis og q-axis components osv.