Megger DCM305E User manual

User manual
DCM305E
Earth Leakage Clampmeter
99 Washington Street
Melrose, MA 02176
Phone [phone]
Toll Free 1-800-517-8431
Visit us at www.TestEquipmentDepot.com

2
GRead First
GSafety 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.
■Do not use the clamp meter if the instrument looks damaged
■Do not use the clamp meter if the tester 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 may be impaired.
■Ensure hands are kept behind the barrier / hand guard when making
measurements.
■Special precautions are necessary when operating in situations where
exposed live parts at dangerous voltages may be encountered.
Personal protective equipment (not supplied with the instrument)
should be used.
■Use caution with voltages above 30 V AC RMS, or 60 V DC. These
voltages pose a shock hazard.

3
CAT IV
Measurement category IV: Equipment connected between the origin of the
low-voltage mains supply outside the building
and the consumer unit.
CAT III
Measurement category III: Equipment connected between the consumer
unit and the electrical outlets.
CAT II
Measurement category II: Equipment connected between the electrical
outlets and the user’s equipment.
Symbols as marked on the instrument and
instruction card
FRisk of electric shock
GSee instruction card
tEquipment protected by double or reinforced insulation
Low battery
gEarth
aAC measurement
cConforms to EU directives
Application around hazardous exposed live conductors is
permitted
Do not discard or throw away this product
GCaution
Take sufficient care not to apply shock, excessive vibration or force to the jaw
If the meter is used in the vicinity of equipment that generates large
electromagnetic fields, the display may become unstable or the measurements
may be subject to large errors.

4
Power Off / On
■The instrument displays battery capacity when powering up. Replace
batteries when 0% is displayed.
Auto Power Off Enable / Disable

Auto Hold Enable / Disable
In the AUTOHOLD mode, if the measured value remains within ±10 counts
over 10 measuring cycles the instrument will beep 3 times; the measured
value will be held on the display and “AUTOHOLD” will be displayed.
Subsequently if the measured value changes by ±10 counts, the instrument
will beep; “AUTOHOLD” will disappear and the instrument will revert to
displaying the new readings until the next AUTOHOLD conditions are met.
Note: When the AUTOHOLD activates, the displayed reading will be held for 3
seconds if the clamp jaws are removed from the conductor/s. During this time
the HOLD key may be pressed to hold the reading indefinitely.
Auto Backlight
The Auto backlight on the display activates automatically when the instrument
is used in very poor light locations
Test Equipment Depot - 800.517.8431
99 Washington Street, Melrose, MA 02176
TestEquipmentDepot.com

6
AC Current
Leakage Current Measurement
Recommended applications of instrument with respect to conductors.
Note: Measurements made on the earth conductor only will indicate current
in the earth conductor but not the entire installation.
GCAT III 300 V with respect
to earth for the jaw.
Barrier for hand guard.
GDo not hold the
instrument above the barrier.

7
Single / 1 phase
3 wire / 3 phase
Single / 1 phase
3 wire / 3 phase

4 wire / 3 phase + neutral
Data Hold
Note: Data Hold beep guard
The internal sounder will beep continuously with the LCD display flashing in
the Data Hold mode when the measured signal is 50 counts larger than the
LCD reading.
4 wire / 3 phase + neutral
Test Equipment Depot - 800.517.8431
99 Washington Street, Melrose, MA 02176
TestEquipmentDepot.com

9
Peak Hold
(forcing into the manual range mode)
Low Pass Filter
(forcing into the manual range mode)
■The cut-off frequency of the low pass filter is about 100 Hz with an
attenuation characteristic of approximately -24 dB / octave.

10
Auto Range / Manual Range