LEM LH240 User manual

LH240
LH1040
LH2040
LH2015
AC/DC Clamp On Multimeters
Pinces Multimétriques AC/DC
AC/DC Zangen-Multimeter
Multimetri tenaglia c.a./c.c.
Multímetros de inserción de C.A./C.C.
Operating Instructions
Mode d’emploi
Bedienungsanleitung
Istruzioni per il funzionamento
Instrucciones de Funcionamiento

1
CONTENTS PAGE
1 INTRODUCTION .................................... 2
1.1 Instrument Features ........................... 3
2 SPECIFICATION ..................................... 4
2.1 Electrical Data...................................... 4
2.2 General Data ....................................... 7
3 OPERATING INSTRUCTIONS ................ 8
3.1 Current Measurement ........................ 9
3.2 Resistance Measurement .................. 9
3.3 Voltage Measurement ....................... 11
3.4 Diode Test .......................................... 11
3.5 Analogue Output ................................. 11
4 SAFETY ................................................... 13
5 BATTERY REPLACEMENT ..................... 14
6 WARRANTY ............................................. 15
7 OTHER PRODUCTS ................................ 16
Issue 4 05/06/97

2
1. INTRODUCTION
The advanced design of the LH series instruments
ensures reliable and accurate measurements under a
wide range of operating conditions. Measurement
features include:
•Non-intrusive AC/DC current
•True RMS for complex and distorted waveforms
•AC/DC current component analysis
•Autoranging and Autozeroing
•AC/DC Volts *
•Ohms, Continuity and Diode Test *
•Max RMS (surge) and Data Hold
•Analogue outputs for recoder, logger or oscilloscope
*
* LH40 series only (LH240, LH1040, LH2040)
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
1.1 Instrument Features

3
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 MAX/ )))) selection.
MAX holds the maximum RMS value when in the
current or volts mode.
)))) selects continuity buzzer when in Ohms mode *
(5) Push button switch for display HOLD
(6) Sliding safety shutter allowing access to either the
test lead input terminals or the analogue output
port *
(7) V out - Analogue output port *
(8) and (9) - Test lead input terminals *
Fig. 1
Instrument Features
2. SPECIFICATION

4
2.1 Electrical data
(All accuracies stated at 23°C ± 1°C)
2.1.1 Current measurement
(DC, DCRMS*, ACRMS)
LH240
Measuring range ................ 0 - 200A DC or AC pk
Autorange facility 40A / 200A
Resolution ......................... 10mA in 40A range
100mA in 200A range
Accuracy I > 5A............... ± 1.3% rdg ± 3 digits
I < 5A .............. ± 0.2A
LH1040
Measuring range ................ 0 - 1000A DC or AC pk
Autorange facility ............... 400A / 1000A
Resolution ......................... 100mA in 400A range
1A in 1000A range
Accuracy I > 15A............. ± 1.3% rdg ± 3 digits
I < 15A ............ ± 0.5A
LH2040/LH2015
Measuring range ................ 0 - 2000A DC or AC pk
Autorange facility ............... 400A / 2000A
Resolution ......................... 100mA in 400A range
1A in 2000A range
Accuracy I > 25A............. ± 1.3% rdg ± 3 digits
I < 25A ............ ± 1.0A
Frequency range ................ DC and 15Hz to 1kHz in
DCRMS
15Hz to 1kHz in ACRMS
Frequency characteristics above 1kHz
Signal Amplitude ................ 3dB @ 5kHz
6dB @ 10kHz
Crest factor ........................ 6 maximum
Maximum overload ............ 10,000A or ACRMS x
frequency <400,000
Amps ACRMS or DCRMS* offer AC or DC coupling of
the amps measurement respectively.
2.1.2 Max RMS Current

5
This function is actuated by pressing MAX/ )))) when in
DC, DCRMS*, ACRMS Amps. No polarity indication is
given for DC readings. Typical acquisition time is
100ms
Accuracy .......................... ± 2% rdg ± 4 digits
Frequency Range............... DC and15 Hz to 1kHz in
DCRMS *
15 Hz to 1kHz in
ACRMS
Crest Factor........................ 6 maximum
2.1.3 Voltage measurement*
(DC,ACRMS)
Measuring range................. 0-600V
Autorange Facility............... 400V / 600V
Resolution.......................... 100mV in 400V range
1V in 600V range
Accuracy AC/DC............. ± 1% rdg ± 3 digits
AC < 20V......... ± 1V
Frequency Range............... DC in DC
15 Hz to 1kHz in
ACRMS
Maximum Overload ............ 1000V
Crest Factor ....................... 6 maximum
2.1.4 Max RMS Voltage *
This function is activated by pressing MAX/ )))) when in
DC or ACRMS. No polarity indication is given in DC.
Typical acquisition time is 100mS
Accuracy .......................... ± 2% rdg ± 4 digits
Frequency Range............... 15 Hz to 1kHz in
ACRMS
Crest Factor........................ 6 maximum
2.1.5 Diode Test *
Measurement of the voltage drop across a forward
biased diode.
Measuring range ................ 0-2V
Resolution .......................... 1mV
Accuracy............................ ± 1% rdg ± 2 digits
Input protection................... 600V
(DC or sinewave RMS)
2.1.6 Resistance Measurement *
Measuring range ................ 0-4 kΩ

6
Autorange Facility............... 400Ω/4kΩ
Resolution .......................... 100mΩin 400Ωrange
1Ωin 4kΩrange
Accuracy ........................... ± 1% rdg ± 3 digits
Input protection................... 600V
(DC or sinewave RMS)
2.1.7 Continuity *
This function is actuated by pressing the MAX/))))
button when in Ωmeasurement. The buzzer will sound
for values of resistance below ≈50Ω.
2.1.8 Analogue Output (Current Measurement) *
An analogue output of the measured current is
provided for use with oscilloscopes and recording
equipment. This can be accessed when the voltage
input terminals are blocked off by the sliding safety
cover. The output, either instantaneous or rms, is
switch selectable by a slider switch located in the
battery compartment.
Output voltage in all ranges:
LH240.................... 5mV/A
LH1040.................. 1mV/A
LH2040.................. 0.5mV/A
Accuracy............... ± 1.3% rdg ± 1mV (RMS)
± 1.3% rdg ± 7mV
(Instantaneous)
Frequency Range.. DC -1kHz Instantaneous
DC and 15Hz to 1kHz true RMS
Frequency characteristics above 1kHz.
Signal / Amplitude . 3dB @ 5kHz
6dB @ 10kHz
The analogue output adapter plugs into the front of the
instrument and the output is obtained from a standard
BNC plug.
2.2 General Data
2.2.1 Display
SAFETY WARNING
Before removing the battery cover,
make sure that all external voltages are
disconnected from the instrument. For
certainty remove all leads.

7
Display 4000 count 12mm high characters.
- + Low battery indicator
Pk Max RMS Amps or Volts
∼
∼∼
∼AC
---- DC, DCRMS *
Diode *
kΩOhms *
)))) Continuity *
HHold H
2.2.2 Power Supply
Battery Type 9V Alkaline PP3 ,NEDA1604 or IEC
6LR61
Battery life typically 40 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
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”

8
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 *
Analogue Output lead *
Carrying case
Operators manual
Cleaning................ The unit can be cleaned
with an isopropanol
impregnated cloth.
Do not use abrasives or other
solvents.
3. OPERATING INSTRUCTIONS
The instrument function is selected by a rotary switch
with the following positions :-
The instrument function is selected by a rotary switch with the
following positions :-
OFF Instrument off
V ---- Volts DC *
V∼
∼∼
∼Volts ACRMS *
Diode measurement *
ΩOhms measurement *
A∼
∼∼
∼Amps ACRMS (AC Component)
A ---- Amps DC (DC Component)
A ∼
∼∼
∼Amps DCRMS (AC+DC) *
3.1 Measurement of AC or DC current

9
•Remove any Voltage test leads from the
instrument.
•Move the rotary switch to Amps AC, DC or
DCRMS*.
•Wait until the autozero operation has completed
and the display reads 00.00 (LH240), 000.0
(LH1040, LH2040, LH2015) to within ±3 digits.
•Press the trigger to open the jaws and clamp them
around the current carrying conductor as shown in
Fig. 2
•Read the display
•Use the HOLD button to freeze the display.
•Use the
))))/MAX button to measure the max RMS
current.
•Note that the Amps autozero is initiated by the
movement of the rotary switch from the Ωposition
to the Amps measurement positions. If, after a
high current measurement, the display does not
return to zero, then a re-autozero can be initiated
by the movement of the rotary switch into and out
of the Ωselection position for the LH40 series and
from OFF to Amps DC for the LH2015.
3.2 Resistance Measurement *
•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.
•Move the rotary switch to the Ωposition.
•Apply the test leads across the component whose
resistance is to be measured. Read the displayed
value.
•Use the HOLD button to freeze the display. Use
the ))))/MAX button to select the continuity facility.
The buzzer will sound for resistance
measurements below ≈50Ω.