4-Channel Power Meter LMG450
Universal Meter for Motors, Power Electronics
and Energy Analysis
Best
Accuracy
0.1%
LMG450 e 01.07
LMG450
General
The four-channel LMG450 power
meter is another advanced
product from ZES ZIMMER
LMG series of precision power
meters, tried and tested and
with great acceptance in the
market. It is designed as a universal meter for the entire field
of power electronics and network analysis. It can be used in
practically all power electronics
applications, in development
and test systems, in quality assurance and maintenance.
It is fully frequency inverter
compatible.
Of course, it can also be used
for measurements in motors,
transformers, conventional and
switched power supply units.
It is also suitable for mains
analysis measurements.
Easy operation thanks to
colour graphics display and
hotkeys for important
measured values
Status bar
Various value tables can be
called on the colour graphics
display at the press of a key,
either with six values in large
letters, which can also be read
at a glance from a greater
Channel 1 with 11 measuring values Range setting and scaling
distance, with twelve values
or with up to 40 values e.g. in
range setting or in harmonics
table. The graphics display
allows scope and plot functions
for waveform and timing diagrams, as well as xy diagrams or
bar charts for the harmonics.
The status bar at the top of
each display menu shows the
input level of the four voltage
and the four current inputs – an
important item of information
for the quality of the measurement.
The display also indicates what
groups, A and B, the input
channels are switched to and
which signals the groups are
synchronised to.
Measurement inputs
Scope function for waveform of sampling values Plot function of calculated values
The direct measurement inputs
for voltage and current have a
very wide dynamic range:
Eight voltage ranges from 6V to
600V, and six ranges for current
from 0.6A to 16A.
A further voltage input (six
LMG450 – rear view
ranges from 0.12V to 4V),
designed for isolating current
sensors, extends the current
measuring range almost indefinitely. With the help of the
special current clamps supplied
by ZES ZIMMER and designed
for the LMG450, current can be
measured during running operations, without interrupting the
current path.
Compensated current clamp
Part No. L45-Z06
A special current measuring device is the
compensated current clamp by ZES ZIMMER.
It features electronic compensation of amplitude
and delay errors. Even at low current levels of
1A to 40A, measurement is exact in the frequency
range from 5Hz to 20kHz. Due to its high dynamic
common-mode rejection, this current clamp is also
very suitable for carrying out measurements at the
frequency inverter output.
Various methods of applying current to be measured
4mm safety sockets
Direct measurement
0.6 ... 16A (6 Ranges)
DC ... 20 kHz
600V CAT III
Compensated current clamp L45-Z06
PSU200/400/600/700
Precision current transducer
1A ... 700Apeak
DC ... 20kHz
(300kHz, bandwidth of sensor
is limited by LMG450)
Standard current clamps
with current outputs >0.5A
100A ... 3000A
45Hz ... 3kHz
Compensated
ZES current clamps
1.2A ... 40A (6 Ranges)
5Hz ... 20kHz
Magneto-resistive
current transducer modules
5A ... 50A
DC ... 20KHz
4 independent power measuring channels
The current and voltage paths
of the four power measuring
channels are all isolated from
each other and from earth.
This allows a high degree of
measuring freedom in many
different power measurement
applications.
The adjacent table shows vari-
High power batterie
chargers (3Ø -> DC)
ous types of wirings for grouped
and individual measurement
channels. The table also assigns
application examples for the
respective types of wiring.
Rectifier section of
inverters (3Ø -> DC)
inverters (DC -> 3Ø)
Power measurement channels
1 and 4 can each be synchronised to their input signals
(fundamental waves etc.)
independent of each other.
Channels 1 and 4 are then the
Power supplies with
1Ø Transformers with
synchronisation references for
the other channels contained in
groups A and B.
3Ø laods with auxiliary
This is a very useful method for
carrying out efficiency measurements for equipment where the
input and output have different
frequencies, for example a
3-phase frequency inverter with
single-phase mains supply.
Wiring settings in () are featured
by option „Star-Delta Conversion“
Standard current clamps with
voltage/current (<0.5A)
outputs
10A ... 200A
45Hz ... 3kHz
Hall effect transducers
5A ... 200A
DC ... 20kHz
HD15 sockets
for external sensors
DC/AC current clamps with
voltage output
e.g. for oscilloscopes
10A ... 200A
DC ... 20kHz
Ch 1 Ch 2 Ch 3 Ch 4
4Ø 4W / 4Ø 5W
1Ø 2W 1Ø 2W 1Ø 2W 1Ø 2W
3Ø 3W / 3Ø 4W / 4Ø 4W 1Ø 2W
3Ø 3W (Aron) 3Ø 3W (Aron)
3Ø 3W (Aron) 1Ø 2W 1Ø 2W
Device Measured Value Ch 1 Ch 2 Ch 3 Ch 4
4Ø motors Power of all windings Phase 1 Phase 2 Phase 3 Phase 4 4+0
Output section of
1Ø -> 3Ø inverter
Low power motor
drives
multiple outputs
multiple output
windings
supplies
3Ø -> 3Ø inverter
High power motor
drives
3Ø -> 1Ø
AC power source
Input and output
power, efficiency
Input power,
rectifier efficiency
Output power,
chopper efficiency
Input and output
power, efficiency
Input and output
power, efficiency
Input and output
power, efficiency
Complete input power Phase 1 Phase 2 Phase 3
Input and output
power, efficiency
Input-, output- and
DC-Bus power,
efficiency
Phase 1 Phase 2 Phase 3 DC-Out
Phase 1 Phase 2 Phase 3 DC-Bus
AC-Out 1 AC-Out 2 AC-Out 3 DC-Bus
AC-Out 1 AC-Out 2 AC-Out 3 Phase 1
DC-Out 1 DC-Out 2 DC-Out 3 Phase 1 3 +1
AC-Out 1 AC-Out 2 AC-Out 3 AC-In 3+1
Aux. AC
or DC
AC-In 1 AC-In 2 AC-Out 1 AC-Out 2
AC-In 1 AC-In 2 DC-Bus AC-Out
Appropriate setting
Group A Group B
of wiring
3+1
(UD I* -> U* I*)
3+1
(UD I* -> U* I*)
3+1
(UD I* -> UD ID)
3+1
(UD I* -> U* I*)
3+1
(UD I* -> UD ID)
2+2
(UD I* -> UD ID)
2+2
(UD I* -> U* I*)
V
U
4
A
A
I
3
I
4
U
2
A
A
I
1
I
2
V
U
1
V
Aircraft
electrical
system
V
U
3
3Ø
f=400Hz
3Ø
f=60Hz
˜
˜
˜
3
f=var
1
f=50Hz
L
N
V
U
4
A
I
4
A
V
U
1
V
U
2
V
U
3
A
I
1
A
I
2
I
3
Motor
Measurement on two systems
with different frequencies
In wiring A:1+2 B:3+4, the
ARON circuit is two times used.
The block diagram shows that
60Hz -> 400Hz
only one LMG450 is needed for
complete measurement.
Generally frequency converters
for speed variable drives or
frequency conversion have no
neutral on input or output.
1
Setting of global parameters,
e.g. wiring (see table at
previous page)
2
Configuration of measuring
inputs and sychronisation
source for group A
The following block diagram
applies wiring A:1+2+3 B:4 and
is typical for a low power speed
50Hz -> f=variable
variable drive. This example is
used to explain the settings
and displays of the LMG450.
1
The screenshots were made with
the free software BMP2PC from
ZES ZIMMER.
2
3
Configuration of measuring
inputs and synchronisation
source (same as picture ,
2
but for group B)
4
Measuring ranges, autorange
or manual, setting of scaling
factors for external CT’s or
VT’s (group A)
4
5
Measuring ranges, autorange
3
or manual, setting of scaling
factors for external CT’s or
VT’s (group B)
6
Display of different plugged
external current sensor
devices from ZES ZIMMER,
here the bottom one is in use
(enabled)
5 6
Scope of power (yellow),
7
current (red) and voltage
(green) of the frequency
converter single phase input
8
Scope display of the low
pass filtered 3Ø output, the
chopper frequency is no more
contained because of being
outside the filtered range
Large display with
9
six important values of the
frequency converter input,
measured in group B
10
Phase values and summing
values of the frequency
converter 3Ø output gives a
quick overview (group A)
11
Efficiency, slip, speed and
other interesting values
calculated by user defined
formulas
12
The formula editor provides
the individual calculations
shown in picture
11
7
9 10
8
13
Vector display of 3Ø systems
immediately checks the phase
sequence and shows phase
interchanges
14
Plot display works like a strip
chart recorder and can plot
all measured or formula
calculated values
15
Harmonic analysis conform to
CE standards
(precompliance tests)
16
Frequency spectrum for
current, voltage (as bar chart),
with CE-limits, linear or
logarithmic
11
13
12
14
15
16
3
f=var
1
f=50Hz
L
N
V
U
4
A
I
4
A
V
U
1
I
3
Motor
A
I
1
V
U
3
V
U
2
A
I
2
All necessary functions
in the basic device:
- Printer interface
- RS232 interface
- Formula editor
- Harmonics analysis for
CE pre-compliance
All necessary functions are
included in the basic device at
reasonable price.
Printer and RS232 interfaces,
formula editor, harmonics
analysis of current and voltage
for pre-compliance tests in
accordance with EN61000-3-2.
Options
- Star-Delta Conversion
Part No. L45-O6
Formula editor: the window shows the available mathematical
formulae, functions and logical conditions
50Hz -> f=variable, instrument for motor measurement in I∗ U∆ wiring
For detailed test and evaluation of 3Ø motors the electrical
quantities for each winding
phase is needed. In some cases
you have access to the motor
terminal block with start and
end of all three windings. Then
you can measure all what you
need. But in most cases the
motor has only three terminals
and the internal star point or
the delta winding as to measure
its current is not accessible.
Also far away from the motor
you have only the three wires.
With the option star-delta conversion you have the capability
to calculate the not accessible
values (e.g. voltages, currents,
power, harmonics). This intelli-
Program example for the monitoring of overvoltage and
undervoltage
gent solution with an additional
DSP works well at all waveforms
and every unbalance of mains
and load. Simply connect the
voltage paths in delta and click
the current clamps around the
wires. Select the internal connection of your load and press
the „Link“ softkey.
Calculation of the real values in the star connected winding
phases (wiring: 3+1, U∆ I∗ -> U∗ I∗)
Further options:
Flicker meter
(Part No. L45-O4)
IEEE488 interface
(Part No. L45-O1)
Interpretation of the complete
SCPI, as well as the LMG450
specific command set. The data
transfer yields up to 1Mbyte/sec.
Disk or memory card
(Part No. L45-O2F or L45-O2)
The two memory media, disk or
memory card, can be used as
required. They serve to record
measured and sampled values
and to save and recall device
settings (setups).
Compliant to EN61000-4-15.
The evaluation of the voltage
fluctuations by currents up to
16A compliant to EN61000-3-3,
by currents up to 75A compliant
to EN61000-3-11.
Process signal interfaces,
digital and analog inputs
and outputs
(Part No. L45-O3)
To monitor further process
magnitudes like revolution,
torque etc. With assistance of
the formula editor efficiency
and other magnitudes can be
deduced and be applied as control parameters.
Harmonics up to 99th
from U, I and P
(Part No. L45-O8)
The harmonics up to 99th
option can be used to analyse
current, voltage and power
related to the fundamental
ranging from 1Hz to 1.2kHz.
It is possible to detect
interharmonics by a selectable
division factor giving a new
fundamental as reference.
Calculation of the real values in the delta connected
winding phases (wiring: 3+1, U∆ I∗ -> U∆ I∆)
Transients
(Part No. L45-O5)
The transients option detects
peaks and dips up to a resolution of 20µsec, scanning
taking place at 50kHz.
Torque determination
(Part No. L45-O16)
Precision Power Meter Series
LMG calculates torque and
speed of three-phase asynchronous motors from motor current
and voltage without torque
measuring shaft.
Dimensioning of insulation
for all standard low voltages
The measurement inputs are
dimensioned for 600V/CAT III,
with option L45-O15 up to
1000V. This makes it possible to
measure in all standard 3-phase
low voltage networks.
The adjacent table shows that
the voltage “Line to Neutral/
Earth” is always less than 600V.
3 Phase/
4 Wire
66/115V 115V 66V
120/208V 208V 120V
230/400V 400V 230V
277/480V 480V 277V
400/690V 690V 400V
3 Phase/
3 Wire
120V 120V 69V
240V 240V 139V
500V 500V 289V
1000V 1000V 578V
Line to Line
Voltage
Line to
Neutral/Earth
Technical Data
Voltage measuring ranges
Nominal value /V 6 12.5 25 60 130 250 400 600
Maximum trms value /V 7.2 14.4 30 60 130 270 560 720
Maximum peak value for full scale /V 12.5 25 50 100 200 400 800 1600
Overload capability 1500V for 1s
Input impedance 1M
Current measuring ranges
Nominal value /A 0.6 1.2 2.5 5 10 16
Maximum trms value /A 1.3 2.6 5.2 10 18 18
Maximum peak value for full scale /A 1.875 3.75 7.5 15 30 60
Overload capability 18A permanent, 50A for 1s, 150A for 20ms
Input impedance 2mΩ
Isolation All direct current and voltage inputs of power measuring channels against each other and against earth isolated, max. 600V/CAT III
Voltage measuring ranges for external
isolated current transduceers
Nominal value /V 0.12 0.25 0.5 1 2 4
Maximum trms value /V 0.15 0.3 0.6 1.2 2.5 5
Maximum peak value for full scale /V 0.25 0.5 1 2 4 8
Overload capability 250V for 1s
Input impedance 100kΩ, 10pF
Measuring range selection Automatic, manual or remotely controlled
Measuring accuracy
Accuracies based on:
1. sinusoidal voltage and current 4. definition of power range as the product of
2. ambient temperature 23 °C current and voltage range, 0 ≤ IλI ≤ 1, (λ=Power factor=P/S)
3. warm up time 1h 5. calibration interval 12 month
Other values All other values are derived from the current, voltage and active power values. Accuracies for derived values depend on the
functional relationship (e.g. S = I * U, DS/S = DI/I + DU/U)
Synchronization The measurement is synchronized on the signals period. There is a choice to determine the period from u(t), i(t), p(t), further
u
frequency inverter and amplitude modulated electronic ballast, synchronization also with external signal or „Line“
Scope function Graphical representation of sampled values over the time
Plot function Time diagram of max. four readings, minimal resolution 50ms
Harmonic analysis prCE Harm
Harmonic analysis Harm100
Fundamental in the range from 1Hz to 1.2kHz. By selectable integer divider (1...50) a new reference fundamental can be created
as to detect interharmonics.
Flicker measuring
Transients – monitoring and storing
selectable recording duration from 0.05 to 60 seconds. Adjustable pre-trigger, different possibilities of triggering
Computer interfaces
Remote control All functions can be remote controlled, keyboard lock for measuring parameters available
Output data Output of all readable data, data formats equal for all interface types, SCPI command set
Transfer rate RS232: max.115200 Baud, IEEE488.2: max. 1MByte/sec
Printer interface
Processing signal interface
• four analog inputs for registration of process magnitudes (16Bit, ±10V, 1kHz)
• four analog outputs for output of readings or measured magnitudes (16Bit, ±10V, 100kHz)
• four digital inputs for registration of states (1kHz, ULOW<1V, UHIGH=4...60V/2.5mA)
• four digital outputs to signal states and alarms (open collector, output high max. 30V@100µA, output low max. 1.5V@100mA)
• one input for registration of frequency (0.1Hz...500kHz) and rotation direction of motors (ULOW<1V, UHIGH=4...10V, 1MΩ)
In- and outputs are isolated groupwise against each other and against the other electronics (testing voltage 500V)
Ω, 20pF
Measuring accuracy
Voltage 0.2+0.2 0.1+0.1 0.05+0.05 0.2+0.2 0.3+0.4
Current (direct) 0.4+0.4 0.15+0.1 0.05+0.05 0.2+0.2 0.5+0.5
Active power (direct) 0.5+0.5 0.2+0.1 0.07+0.08 0.3+0.2 0.6+0.5
Current (via ext. current transducer) 0.2+0.2 0.1+0.1 0.05+0.05 0.2+0.2 0.3+0.4
Active power (via ext. current transducer) 0.3+0.3 0.15+0.1 0.07+0.08 0.3+0.2 0.6+0.5
2
(t), i2(t) by using a settable filter . By this very stable readings are achieved, even at signals of pulse width modulated
Measuring of current and voltage according to EN61000-4-7 with evaluation according to EN61000-3-2 (Pre-compliance)
Analysis of current, voltage and power up to 99th harmonics (max. 10kHz), in total 100 harmonics, when including DC part.
Flicker Meter according to EN61000-4-15 with evaluation according to EN61000-3-3
Storing and graphical displaying of transients with a resolution of 20µs. Storing depth is 1.4 Millions sample values/channel,
Interfaces: RS232 and IEEE488.2, only one interface can be used at the same time
Parallel PC-Printer interface with 25-pin SUB-D socket for printing measuring values, tables, graphics to matrix, inkjet or laser printers
25 pin SUB-D socket with (The option processing signal interface can be built in twice):
DC 1Hz..1kHz 45...65Hz, AC-Coupling 1kHz..5kHz 5kHz...20kHz
± (% of measuring value + % of measuring range)
Other data
Display STN colour display, 320 x 240 pixel, 5,7’’
Dimensions - Bench case, W 320mm x H 147mm x D 307mm
- 19‘‘-chassis, 84PU, 3HU, D 307mm
Weight about 6,5kg
Protection class EN61010 (IEC1010, VDE0411), protection class I, overvoltage category III
Electromagnetic compatibility EN50081, EN50082
Protection system IP20 in accordance to DIN40050
Operating/storage temperature 0...40°C, -20...50°C
Climatic class KYG in accordance to DIN40040
Power supply 85...264V, 47...440Hz, about 45W
LMG450 accessories
ZES ZIMMER compensated current clamps
Nominal value /A 1.25 2.5 5 10 20 40
Permissible trms value /A 2.5 5.0 10 20 40 80
Permissible peak value for full scale /A 3.75 7.5 15 30 60 120
Overload capability 500A for 1s
Max. cord diameter 12mm
Isolation 300V/CATIII, 600V/CATII
Part No.
L45-Z06 (1 pc.)
L45-Z07 (Set of 4 pc.)
Hall current sensors for range extension
Part No. Current Supply
nominal trms peak
L45-Z28-Hall50 35A 50A 70A Internally
L45-Z28-Hall100 60A 100A 120A by LMG450
L45-Z28-Hall200 120A 200A 240A via HD15
L45-Z29-Hall300 250A 300A 500A Externally e.g. with
L45-Z29-Hall500 400A 500A 800A ZES power supply for
L45-Z29-Hall1000 600A 1000A 1200A up to four sensors
L45-Z29-Hall2000 1000A 2000A 2100A Part No. SSU-4
Measuring accuracy of clamp
Current 1.5+0.25 0.4+0.15 0.15+0.05 0.3+0.15 1.0+0.25 4.0+0.5
Phase 6 3 0.5 2 6 20
Current: ± (% of measuring value + % of measuring range) / Phase: degrees
1Hz...10Hz 10Hz...45Hz 45Hz...1kHz 1kHz...5kHz 5kHz...20kHz 20kHz...50kHz
Current transducers with Hall effect
sensors for range extension of LMG450,
DC...20kHz, accuracy class 0,5
connected to LMG450 via HD15 sensor
input, incorporated EEPROM for scaling
and adjustment data as well as data for
automatically setting of appropriate
current range
Power supply unit for up to 4 Sensors
Part No. SSU-4
Adapter for 3-phase measurements
Part No. LMG-MAK3
Longtime Data Logging NDL5
Part No. NDL5
LMG450 application software
Product name (Part No.)
LVDRV-L45 Driver for LMG450 under LAB-View 5.1.1 for RS232 as well as IEEE488 interface, with programming samples
LWINDRV-L45 Driver for LMG450 under LAB Widows/CVI for RS232 as well as IEEE488 interface, with programming samples
TERM-L5 Data transfer from LMG450/LMG95 to PC via RS232- and IEEE488-interface, recording as ASCII in Microsoft Excel- (CSV) or
ZES-format, or in tables with any separator, visualisation in real time of some selectable measurement values
BMP2PC Bitmap transfer from LMG450/LMG95 to PC via RS232, downloaded screens can be processed and scaled in Windows.
Free download from the website www.zes.com
Power supply unit for up to 4 Sensors for L45-Z29 and PSU-600 series, device fitting under LMG450/95,
design equal to NDL5 (see below)
• CEE-Plug, 5 pins, 16A, 2m supply cord
• CEE-Socket, 5 pins, 16A, for EUT
• Socket for supplying the meter LMG450
• 4mm safety sockets, measuring access to current and voltage
• Safety acc. IEC61010: 300V/CAT III
Longtime-data logging to harddisk for LMG450/LMG95
Communication via Internet/Ethernet, even when recording
Subject to technical changes, especially to improve the product, at any time without prior notification.
ZES ZIMMER Electronic Systems GmbH
Tabaksmühlenweg 30, D-61440 Oberursel/Ts.
Tel. ++49 6171 628750 Fax ++49 6171 52086
http://www.zes.com e-mail: sales@zes.com
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