Megger DCM340 User manual

DCM340
Clampmeter
User Guide

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DCM340
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Safety Information
1. Safety Information
To ensure safe operation and service of the Meter, follow these instructions.
Failure to observe warnings can result in severe injury or death.
Avoid working alone so assistance can be rendered.
To enhance safety, test leads should be disconnected from instrument when not in use.
Do not use test leads or the Clamp Meter if they look damaged.
Do not use the Meter if the Clamp Meter is not operating properly or if it is wet.
Use the Clamp Meter only as specified in the Instruction card or the protection provided
by the Clamp Meter might be impaired.
Special precautions are necessary when operating in situations where exposed live parts
at dangerous voltages may be encountered. Personal protective equipment (not supplied
with this instrument) should be used.
The test leads sould be disconnected from the instrument when making a current
measurement.
Use caution with voltages above 30 V ac rms, or 60 V dc. These voltages pose a shock
hazard.
To avoid false readings that could lead to electric shock and injury, replace the battery as
soon as the low battery indicator ( ) appears.
CAUTION :
CAUTION : If the meter is used in the vicinity of equipment which generates
electromagnetic interference, the display may become unstable or the measurements
show may be subject to large errors.
1.1 Maintenance
Do not attempt to repair this Clamp Meter.
It contains no user-serviceable parts. Repair or serving should only be performed by qualified
personal.
1.2 Cleaning
Periodically wipe the case with a dry cloth and detergent do not use abrasives or solvents.

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Safety Information
1.3 Safety, Hazard and Warning symbols on the instrument
This paragraph details the various safety and hazard icons on the instrument’s outer case.
Icon Description
FWarning: High Voltage, risk of electric shock
GCaution: Refer to user guide.
UK conformity. This equipment complies with current UK legislation
cEU conformity. Equipment complies with current EU directives.
Equipment complies with current ‘C tick’ requirements.
Do not dispose of in the normal waste stream.
tEquipment protected throughout by double insulation.
aAC measurement
dDC measurement
gReference earth connection. Not a protective earth terminal
Battery
CAT IV - Measurement category IV: Equipment connected between the origin of the low-
voltage mains supply and distribution panel.
CAT III -Measurement category III: Equipment connected between the distribution panel and
electrical outlets.
CAT II - Measurement category II: Equipment connected between the electrical outlets and
user’s equipment.
CAT I - Measurement category I: The circuits are not connected to mains.
Measurement equipment may be safely connected to circuits at the marked rating or lower.
The connection rating is that of the lowest rated component in the measurement circuit.

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DCM340
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Operation
2. Operation
2.1 Power On / Off
2.2 Auto Power Off
Auto Power Off disable : Press buttons
(except Hold button) than switch the rotary
knob to power on the Meter.
2.3 AC V / DC V
2.4 Resistance
2.5 Continuity

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Operation
2.6 ACA / DCA
GCAT.III.600 V with respect to earth for the
jaw.
GDo not hold the meter in front of the
Tactile Barrier.
2.7 Hz
2.8 Zero
2: REL: Meter save the displayed offset value
after one press of the ZERO button. The LCD
is displaying the relative value.
3: REL (flashing): A second press of the
ZERO button saves the offset value, with the
present value then displayed.
1: Normal : Press and hold ZERO for ≥2 sec
to return to normal operation and cancel the
offset value.

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DCM340
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Operation
2.9 Data Hold
2.10 Min / Max Hold
2: MAX: Meter is saving the maximum and
minimum value. Maximum value is displayed
3: MIN: Meter is saving the maxi mum and
minimum value. Minimum value is displayed
4: MAX MIN (flashing): Meter is saving the
maximum and minimum values. Present
value is displayed.
1: Normal : Press and hold MIN MAX to
return to normal operation.
2.11 Battery Replacement
Low battery : “ ” is displayed or flashes
when a button pressed.
To avoid false readings that could lead to electric
shock and injury, replace the battery as soon as the
low battery indicator () appears.

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Operation
2.12 Peak Hold
2: PMAX: Meter is saving the peak
maximum and minimum value. Peak
maximum value is displayed.
3: PMIN: Meter is saving the peak maximum
and minimum value. Peak minimum value is
displayed
4: CAL : Press and hold PEAK button ≥3
sec to calibrate the Meter itself for accurate
measurement.
1: Normal : Press and hold PEAK button to
return to normal operation.
2.13 Back Light
Back light Automatic off after 60 seconds.

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DCM340
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Specifications
3. Specifications
Specification Detail
1-1 General Specifications
LCD display digits : 3 3/4 digit large scale LCD readout.
Display count : 4000 counts.
Measuring rate : 1.5 times / sec.
Overrange display : “OL” is displayed for “Ω” functions, shows the real value for
“A” and “V” function.
Automatic power off time : Approximately 30 minutes after
Low battery indicator :
is displayed. Replace the battery when the indicator
appears in the display.
To avoid false readings that could lead to electric shock and
injury, replace the battery as soon as the low battery indicator
appears.
Power requirement : 9 V PP3 / 6LR61 battery.
Rechargeable batteries are not suitable for use with this
instrument.
1-2 Environmental Conditions
Indoor Use.
Calibration : One year calibration cycle.
Operating temperature : 0 °C ~ 30 °C (±80% RH)
30 °C ~ 40 °C (±75% RH)
40 °C ~ 50 °C (±45% RH)
Storage temperature : -20 to +60 °C, 0 to 80% RH (batteries not fitted).
Overvoltage category : IEC 61010-1 600 V CAT.III. CAT.III equipment is designed
to protect against the transients in the equipment in fixed
installations, such as distribution panels, feeders and short
branch circuits and lighting systems in large buildings.
Operating altitude : 2000 m (6562 ft)
Conductor Size : 35 mm diameter.
Pollution degree : 2
EMC : EN 61326-1
Shock vibration : Sinusoidal vibration per MIL-T- 28800E
(5 ~ 55 Hz, 3 g maximum).
Drop Protection : 1.2 m drop to hardwood on concrete floor.

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Specifications
1-3 Electrical Specifications
Accuracy is ±(% reading + number of digits) at 23 °C ±5 °C < 80%RH.
Temperature coefficient : Add 0.2 x (Specified accuracy) / °C, < 18 °C, > 28 °C .
Voltage Function Range Accuracy
Va0~400.0 Vrms
400~600 Vrms
±(1.0%+ 5 dgt) 50
Hz ~ 500 Hz
Vd0~400.0 V
400~600 V
±(0.7% + 2 dgt)
Over voltage protection : 600 V rms
Input Impedance : 1 MΩ // less than 100 pF.
AC Conversion Type : AC Conversion are average sensing rms indication calibrated
to the rms value of a sine wave input.
Resistance and Continuity : Function Range Accuracy
Ω400.0 Ω ±(1% + 3 dgt)
Over voltage protection : 600 V rms
Max. open circuit voltage : 3 V
Continuity check : Internal sounds activates if the resistance of the circuit under
test is less than 30Ω approximately.
AC Current Function Range Accuracy
A~
(50~60 Hz)
0~400.0 A ±(1.5%+ 5 dgt) *1
400~600 A ±(2.0%+ 7 dgt)
A~
(61~400 Hz)
0~400.0 A ±(2.0%+ 5 dgt) *1
400~600 A ±(2.5%+ 7 dgt)
*1 : Over 80% of full scale add ±1.6%
Overload protection : 600 A rms
AC Conversion Type and additional accuracy is same as AC
Voltage.
Position Error : ±1% of reading.
DC Current Function Range Accuracy
Ad0~400.0 A ±(1.2%+ 5 dgt)
400~600 A ±(1.9%+ 7 dgt)
Overload protection : 600 A rms
Position Error : ±1% of reading.

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DCM340
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Specifications
Addition error according to remanence : 1% max. of current crest.
Auto Power Off (APO) The meter will automatically shut itself off after approximately
30 minutes after power on.
Frequency : Hz Function Range Accuracy
20~400 Hz 1 Hz ±(0.1% + 2 dgt)
Overload protection : 600 A rms.
Sensitivity : 3 A rms for ACA (Aa) (>400 Hz Unspecified)
Peak Hold : ±(3% + 15dgt) *>600 Vpeak Unspecified. *>600 A peak
Unspecified.
Min/Max Hold : add ± 15 dgt to accuracy for ACA / DCA.
* Automatically switch to the low resolution range at Peak
Hold and MIN MAX Hold.