2
MULTIMETER EM420B
Read this owner’s manual thoroughly before use
WARRANTY
This instrument is warranted to be free from defects in material and workmanship
for a period of two year.
Any instrument found defective within two years from the delivery date and returned to
the factory with transportation charges prepaid, will be repaired, adjusted, or replaced
at no charge to the original purchaser. This warranty does not cover expandable items
such as batteries or fuse. If the defect has been cause by a misuse or abnormal operation
conditions, the repair will be billed at a nominal cost.
SAFETY INFORMATION
The multimeter has been designed according to IEC-61010 concerning electronic meas-
uring instruments with a measurement category (CAT II 600V) and Pollution degree2
ELECTRICAL SYMBOLS
AC (Alternating Current)
DC (Direct Current)
DC or AC(alternating current or directive current)
Important safety information. Refer to the manual
Dangerous voltage may be present.
Earth ground
Fuse
Conforms to European Union directives
Double insulated.
Low battery
Diode
The maximum values is being held
The display data is being held
Fahrenheit
Centigrade
Continuity test
Measurement with clamp (optional), widening the field of applica-
tions of the meter
Autorange
–
Danger of electrical injury
Warning, Danger. Please pay attention to the passages of this manual
where this symbol is used.
WARNING
To avoid possible electric shock or personal injury, follow these guidelines:
• Do not use the meter if it is damaged. Before you use the meter, inspect the case.
Pay particular attention to the insulation surrounding the connectors.
• Inspect the test leads for damaged insulation or exposed metal. Check the test
leads for continuity. Replace damaged test leads before you use the meter.
• Do not use the meter if it operates abnormally. Protection may be impaired. When
in doubt, have the meter serviced.
• Do not operate the meter around explosive gas, vapor, or dust.
• Do not apply more than the rated voltage, as marked on the meter, between
terminals or between any terminal and earth ground.
• Before use, verify the meter’s operation by measuring a known voltage.
• When measuring current, turn off circuit power before connecting the meter in
the circuit. Remember to place the meter in the circuit. Remember to place the
meter in series with the circuit.
• When servicing the meter, use only specified replacement parts.
• Use with caution when working above 30V ac rms, 42V peak, or 60V dc. Such
voltages pose a shock hazard.
• When using the probes, keep your fingers behind the finger guards on the probes.
• Connect the common test lead before you connect the live test lead. When you
disconnect test leads, disconnect the live test lead first.
• Remove the test leads from the meter before you open the case.
• Do not operate the meter with the cover removed or loosened.
• To avoid false readings, which could lead to possible electric shock or personal
injury, replace the batteries as soon as the low battery indicator appears.
• Do not use the test leads to measure the voltage which is more than 600V or the
current which is more than 10A.
• Remaining endangerment: When an input terminal is connected to dangerous live
potentional it is to be noted than this potential at all other terminals can occur!
• CATII-Measurement Category II is for measurements performed on circuits directly
connected to low voltage installation. Do not use the meter for measurements
within Measurement Categories III and IV.
CAUTION
To avoid possible damage to the meter or to the equipment under test, follow
these guidelines:
• Disconnect circuit power and discharge all high voltage capacitors before testing
resistance, continuity, diodes, or capacitance.
• Use the proper terminals, function, and range for your measurements.
• Before measuring current, check the meter’s fuse and turn power OFF to the circuit
before connecting the meter to the circuit.
• Before rotating Function / Range switch to change functions, disconnect test leads
from the circuit under test.
• Before inserting transistor to the adapter , always be sure all the test leads have
been removed from the meter
• Remove test leads from the meter before opening the battery cover or the case.
MAINTENANCE
To continue protection against fire, replace fuse only with the specified voltage and
currents rating: F 250 mA L 250V, fast action.
To clean the meter, use a damp cloth and mild detergent only, do not use abrasives
or solvents on it.
GENERAL DESCRIPTION
This digital multimetr is compact 3,5 digits digital multimeter for measuring DC and
AC voltage, DC and AC current, resistance, temperature, diode, transistor, continuity,
capacitance ( only EM420B)and battery(only EM420A). It has the functions of polarity
indication, data hold, maximum value hold, overrange indicator and automatic power-
off. It can be operated easily and is ideal instrument tool.
Instruction
1
DISPLAY
– 3,5 digit LCD with a max reading of 1999
2
RANGE button
– The meter defaults to the autorange mode when you measure
the voltage, current or resistance. When the meter is in the autorange mode, AUTO
i s displayed.
To enter and exit the manual range mode:
a) Press RANGE button – The meter enters the manual range mode and the symbol
AUTO turns off.
Each press of the RANGE button increments the range. Then the highest range is
reached, the meter wraps to lowest range
b) To exit the manual range mode, press and hold down the RANGE button for
2 seconds, the meter returns to the autorange mode and the symbol AUTO is
displayed again.
3
FUNC. button
– When you measure the current, pressing this button will switch
the meter between DC function and AC function.
When you measure the temperature, pressing this button will switch the meter
between °F mode and °C mode
When you measure the diode or the continuity functions.
4
POWER switch
– It can be used to turn on/off the meter.
5
FUNCTION/RANGE SWITCH
– This switch can be used to select desired function
and range.
6
10A Jack
– Plug-in connector for the red test lead for current (200 mA ~10 A)
measurement.
7
COM Jack
– Plug-in connector for black(negative) test lead.
8
INPUT Jack
– Plug-in connector for the red test lead for all measurement except
current(≥200mA) measurements.
9
Button
– To turn on or off the backlight, press and hold this button for about
2 seconds. The backlight will turns off automatically about 15 seconds later after
you turn on it.
10
Button
– After pressing the button, the present reading is held on the
display, meanwhile is displayed on the LCD as an indicator. To exit th Hold Mode,
press the button again and the indicator will disappear.
11
Button
– The hold the maximum value, press this button and will appear
as an indicator, the meter will hold the maximum of all readings taken since the
button was pressed. To exit the maximum value hold mode, just press this button
again and will disappear.
In some ranges, the maximum value hold mode is not available.
GENERAL SPECIFICATION
Display:
LCD, 1999 counts, updates 2–3 times/sec
Overrange Indications:
OL shown on display
Battery:
3× 1,5V, AAA
Polarity Indication:
„–„ displayed atomatically
Low Battery Indication:
shown on display
GB
