LEM LH1050 User manual

LH1050
AC/DC Clamp On Power Meter
Operating Instructions

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CONTENTS PAGE
1 INTRODUCTION .................................... 2
1.1 Instrument Features ........................... 3
2 SPECIFICATION ..................................... 4
2.1 Electrical Data...................................... 4
2.2 General Data ........................................ 6
3 OPERATING INSTRUCTIONS ................ 7
3.1 Current Measurement ......................... 8
3.2 Voltage Measurement ......................... 9
3.3 Power 1Ø Measurement .................... 10
3.4 Power 3Ø Measurement .................... 11
3.5 Frequency Measurement .................... 12
3.6 Logging................................................. 12
4 SAFETY .................................................... 13
5 BATTERY REPLACEMENT ..................... 14
6 WARRANTY ............................................. 15
7 OTHER PRODUCTS ................................ 16
Issue 2 02/97

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1. INTRODUCTION
The advanced design of the LH series instruments
ensures reliable and accurate measurements under a
wide range of operating conditions. Power meter
features include:
•AC/DC voltage and current measurement
•Watts, VA, VAR and PF
•Built in 3 phase power capability
•Frequency
•Bargraph for dual parameter display
•REC mode giving MIN, MAX, AVG readings
•Hold function to save a complete data set for
power measurements
•Autoranging and Autozeroing facility
•Digital output for data logging*
The LH series of instruments conform to the latest
international directives and standards concerning
safety and electromagnetic compatibility.
•European Low Voltage Directives 73/23/EEC and
93/68/EEC
•European EMC Directives 89/336/EEC and
93/68/EEC
•Submitted for approval to UL 3111-1
Safety Standards
IEC 1010-1: 1992-09 Safety requirements for
electrical equipment for measurement, control and
laboratory use.
Part 2-032: 1994-12 Particular requirements for hand
held current clamps for electrical measurement and
test.
Part 2-031: 1993-02 Particular requirements for hand
held probe assemblies for electrical measurement and
test.
600V Cat III Pollution degree 2
EMC Standards
RF Susceptibility
EN 50082-1: 1992 3V/m Residential, Commercial and
Light Industry
RF Emissions
EN 50081-1: 1992 Residential, Commercial
and Light Industry
FCC Part 15 Class B
* Requires optional accessory
1.1 Instrument Features

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The main operating features of the instrument are as
follows. See Fig. 1.
(1) Clamp-on jaws for current measurement
(2) Jaw opening lever
(3) Rotary switch for function selection
(4) Push button switch for VA, VAR and PF
measurements in Watts mode. Press and hold for
2 seconds for REC mode (Min, Max, Av.)
(5) Push button switch for HOLD, saves complete
data set when in single phase Watts mode. Press
and hold for 2 seconds for Amps ZERO.
(6) Digital output for logging to a PC.
(7) and (8) - Test lead input terminals
Fig. 1
Instrument Features
2. SPECIFICATION
1
2
4
7
8
3
5
6

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2.1 Electrical data
(All accuracies stated at 23°C ± 1°C)
2.1.1 Current measurement
(RMS and DC)
Measuring range ............... 0 -1000A DC or ACpk
Autorange facility ............... 400A / 1000A
Resolution ......................... 100mA in 400A range
1A in 1000A range
Accuracy
I > 20A ............ ± 1.5% rdg ± 5 digits
I ≤20A ............ ± 1A
All measurements
DC and 30Hz to 1kHz
Maximum overload 10,000A or
RMS x frequency < 400,000
Amps RMS is a true RMS measurement
2.1.2 Voltage measurement
(RMS and DC)
Measuring range................ 0 - 600V DC or AC
Autorange facility ............... 400V / 600V
Resolution.......................... 100mV in 400V range
1V in 600V range
Accuracy V > 40V........... ± 1% rdg ± 5 dgts
V ≤40V........... ± 1V
Maximum overload 1000V RMS
All measurements DC and 30Hz to 1kHz
2.1.3 Watts measurement (Single and 3 Phase)
(RMS and DC)
Measuring range................ 0 - 600kW DC or 425kW
in AC
Autoranging facility............. 40kW, 400kW
600kW
Resolution.......................... 10W in 40kW
100W in 400kW
1kW in 600kW
Accuracy W > 2kW ............ 2.5% rdg ± 5 dgts
W < 2kW ............ ± 0.08kW
Frequency range DC and 30Hz to 1kHz
Current Range ................... 30A to 1000A Pk
Voltage Range................... 40V to 600V RMS

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Maximum input 600VRMS / 1000A Pk
Maximum overload 1000V RMS / 10,000A
2.1.4 VA measurement (Single and 3 Phase)
(RMS and DC)
Measuring range................ 0-600kVA DC or 425kVA
in AC
Autorange Facility 40kVA, 400kVA,
600kVA
Resolution.......................... 10VA in 40kVA
100VA in 400kVA
1kVA in 600kVA
Accuracy VA > 2kVA ...... ±2.5% rdg ±5 dgts
VA < 2kVA ...... ±0.08kVA
Frequency Range............... DC and 30Hz to 1kHz
Current Range ................... 30A to 1000A Pk
Voltage Range................... 40V to 600V RMS
Maximum input 600V RMS / 1000A Pk
Maximum Overload 1000V RMS / 10,000A
2.1.5 VAR measurement (Single and 3 Phase)
(RMS)
Measuring range................ 0-425kVAR
Autorange Facility 40kVAR, 400kVAR,
600kVAR
Resolution.......................... 10VAR in 40kVAR
100VAR in 400kVAR
1kVAR in 600kVAR
Accuracy VAR > 2kVAR . ±2.5% rdg ±5 dgts
VAR < 2kVAR . ±0.08kVAR
Frequency Range............... 30Hz to 1kHz
Current Range ................... 30A to 1000A Pk
Voltage Range................... 40V to 600V RMS
Maximum input 600V RMS / 1000A Pk
Maximum Overload 1000V RMS / 10,000A
2.1.6 Power Factor (Single and 3 Phase)
Measuring range 0.3 cap 1.0 ..0.3 ind
(72.5øcap ..... 1.0 .... 72.5° ind)
Resolution.......................... 0.01
Accuracy............................ ± 3°
Frequency range................ 30Hz to 1kHz
Voltage range..................... 40V to 600V RMS
Current range..................... 30A Pk to 1000A Pk
Measurement overload ...... 1000V / 10,000A

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2.1.7 Frequency measurement
(From Current or Voltage sources)
Measuring range ............... 30Hz to 1kHz
Resolution.......................... 0.1Hz
Accuracy 40 - 70Hz............ ± 0.5% rdg
30 - 1000Hz ....... ± 1% rdg
Current Range ................... 30A to 1000A Pk
Voltage Range................... 40V to 600V RMS
2.1.8 Digital output
A digital interface for connection to a PC is available
as an optional accessory for data logging. The
instrument outputs the displayed value. Additional
data is sent when in Watts and Hz settings:
Function Output
Watts.................................Watts, VA, VAR, PF
Hz......................................Hertz, Volts or Amps
Output rate.........................2400 baud
2.2 General Data
2.2.1 Display
Display 4000 count 10mm high characters.
MIN
MAX
AVG
AC+DC Identifies AC, DC or AC + DC
IIIIIIIIIIIII Bargraph display
H
2.2.2 Power Supply
Battery Type 9V Alkaline PP3 ,NEDA1604 or IEC
6LR61
REC Mode minimum,
maximum or average
readings
Low batter
y
indicato
r
Hold
WARNING (See Manual)

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Battery life typically 10 hours continuous operation.
2.2.3 Environmental
FOR INDOOR USE ONLY
Reference conditions. All accuracies stated at
23°C ± 1°C
Temperature coeff. of current ±0.1% of rdg per °C
Temperature coeff. of voltage ±0.1% of rdg per °C
Operating Temperature 0°C to 50°C (32°F to 122°F)
Maximum Relative Humidity 80% for temperatures up
to 31°C (87°F) decreasing linearly to 50% Relative
Humidity at 40°C (104°F)
Storage Temperature -20°C to +60°C (-4°F to 140°F)
Maximum operating altitude 2000m.
2.2.4 Mechanical
Dimensions............ Length 251mm / 9.88”
Width 98mm / 3.86”
Depth 52mm / 2.05”
Weight ................... 500g / 1.1 lbs.
Case Material......... Bayblend T85MN
Jaw Opening.......... 55mm / 2.2”
Accessories ........... Voltage probes
Digital Interface lead *
Carrying case
Operators manual
Cleaning................. The unit can be cleaned
with an Isopropanol
impregnated cloth.
Do not use abrasives or other
solvents.
* Optional accessory
3. OPERATING INSTRUCTIONS
International Symbols
The instrument function is selected by a rotary switch
with the following positions :-
OFF Instrument off
VVolts TRMS
AAmps TRMS
Important Information
(See Manual)
AC + DC
Double Insulation

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WWatts TRMS
W3∅
∅∅
∅3 Phase Watts
Hz Frequency
On power up the instrument enters a calibration mode
in which CAL is displayed. During this period the
instrument must not be clamped on any current
carrying conductors.
3.1 Current Measurement
•Remove any Voltage test leads from the
instrument.
•Move the rotary switch to the Amps position
•Press the trigger to open the jaws and clamp them
around the current carrying conductor as shown in
Fig. 2
•Read the display
•Press the HOLD / ZERO button to freeze the
display. Press and hold (2 seconds) to zero the
display.
•Press and hold the REC button (2 seconds) to
activate the REC mode.
•Press the REC button again to cycle through Min,
Max, Average readings. Press and hold the REC
button (2 seconds) to exit the REC mode.
Fig. 2
Current Measurement
3.2 Voltage Measurement

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•Move the rotary switch to the Volts position.
•Insert the test leads into the sockets on the front of
the instrument, the red lead to the VΩterminal and
the black lead to the COM terminal, as shown in
Fig. 3.
•Apply the test leads across the component whose
voltage is to be measured. Read the displayed
value.
•Press the HOLD / ZERO button to freeze the
display.
•Press and hold the REC button (2 seconds) to
activate the REC mode.
•Press the REC button again to cycle through Min,
Max, Average readings. Press and hold the REC
button (2 seconds) to exit REC mode.
Fig. 3
Voltage Measurement
3.3 Power Measurement (Single phase)
SAFETY WARNING
To avoid possible electric shock and
damage to the instrument, do not attempt to
measure any voltage that might exceed the
maximum range of the instrument - 600Vrms
and 1kHz