Unit UT50E User manual

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Model UT50E: OPERATING MANUAL
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Table of Contents
Title
Overview
Unpacking Inspection
Safety Information
Rules For Safe Operation
International Electrical Symbols
The multimeter Structure
Functional Buttons
Display Symbols
Measurement Operation
A. DC Voltage Measurement
B. AC Voltage Measurement
C. DC Current Measurement
D. AC Current Measurement
E. Measuring Resistance
F. Measuring Diodes & Continuity
G. Frequency Measurement
H. Temperature Measurement
I. Capacitance Measurement
General Specifications
Sleep Mode
Turning on the Auto Display Backlight
Accuracy Specifications
A. DC Voltage
B. AC Voltage
C. DC Current
D. AC Current

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I. Capacitance 31
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C. Replacing the Fuses
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Title
E. Resistance Test
F. Diodes and Continuity Test
G. Frequency
H. Temperature
Maintenance
A. General Service
B. Replacing the Battery
Model UT50E: OPERATING MANUAL
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Overview
Warning
To avoid electric shock or personal injury, read the
"Safety Information" and "Rules for Safe Operation"
carefully before using the Meter.
Digital Multimeters Model UT50E (hereafter referred to
as “the Meter”) is a 4 1/2 digits with steady operations,
fashionable structure and highly reliable hand-held
measuring instrument having 30 measurement positions.
The multimeter uses large scale of integrated circuit with
double integrated A/D converter as its core and has full
range overload protection. The multimeter not only can
measure AC/DC Voltage, AC/DC Current, Resistance,
Capacitance, Temperature, Frequency, Diodes and
Continuity, but also has Data Hold, Full Icon Display and
Sleep Mode features.
The multimeter adopted advanced “co-injection”
technique in order to provide sufficient insulation and
anti-shaking. In addition, theAutomatic Display Backlight
feature enables user to work in a dim condition.
Model UT50E: OPERATING MANUAL
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Unpacking Inspection
Open the package case and take out the multimeter.
Check the following items carefully to see any missing
or damaged part:
In the event you find any missing or damage, please
contact your dealer immediately.
Model UT50E: OPERATING MANUAL
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Item
1
2
3
4
Description
English Operating Manual
Test Lead
Test Clip
Point Contact Temperature Probe
Qty
1 piece
1 pair
1 pair
1 piece

Safety Information
This Meter complies with the standards IEC61010: in
pollution degree 2, overvoltage category (CAT. II 1000V,
CAT. III 600V) and double insulation.
CAT. II: Local level, appliance, PORTABLE EQUIPMENT
etc., with smaller transient voltage overvoltages than
CAT. III
CAT. III: Distribution level, fixed installation, with smaller
transient overvoltages than CAT. IV
Use the Meter only as specified in this operating manual,
otherwise the protection provided by the Meter may be
impaired.
In this manual, a Warning identifies conditions and
actions that pose hazards to the user, or may damage
the Meter or the equipment under test.
A Note identifies the information that user should pay
attention on.
International electrical symbols used on the Meter and
in this Operating Manual are explained on page 8.
Model UT50E: OPERATING MANUAL
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Rules For Safe Operation (1)
Warning
To avoid possible electric shock or personal injury,
and to avoid possible damage to the Meter or to the
equipment under test, adhere to the following rules:
l Before using the Meter inspect the case. Donot
use the Meter if it is damaged or the case (orpart
of the case) is removed. Look for cracks or
missing plastic. Pay attention to the insulation
around the connectors.
l Inspect the test leads for damaged insulation
or exposed metal. Check the test leads for
continuity. Replace damaged test leads with
identical model number or electrical specifications
before using the Meter.
l Do not apply more than the rated voltage, as
marked on the Meter, between the terminals or
between any terminal and grounding.
l The rotary switch should be placed in the right
position and no any changeover of range shall
be made during measurement is conducted to
prevent damage of the Meter.
l When the Meter working at an effective voltage
over 60V in DC or 30V rms in AC, special care
should be taken for there is danger of electric
shock.
l Use the proper terminals, function, and range
for your measurements.
l Do not use or store the Meter in an environment
of high temperature, humidity, explosive,
inflammable and strong magnetic field. The
performance of the Meter may deteriorate after
dampened.
l When using the test leads, keep your fingers
behind the finger guards.
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Rules For Safe Operation (2)
l Disconnect circuit power and discharge all high-
voltage capacitors before testing resistance,
continuity, diodes, capacitance or current.
l Before measuring current, check the Meter’s
fuses and turn off power to the circuit before
connecting the Meter to the circuit.
l Replace the battery as soon as the battery
indicator appears. With a low battery, the Meter
might produce false readings that can lead to
electric shock and personal injury.
l Remove test leads, test clips and temperature
probe from the Meter and turn the Meter power
off before opening the Meter case.
l When servicing the Meter, use only the same
model number or identical electrical specifications
replacement parts.
l The internal circuit of the Meter shall not be
altered at will to avoid damage of the Meter and
any accident.
l Soft cloth and mild detergent should be used
to clean the surface of the Meter when servicing.
No abrasive and solvent should be used to
prevent the surface of the Meter from corrosion,
damage and accident.
l The Meter is suitable for indoor use.
l Turn the Meter power off when it is not in use
and take out the battery when not using for a
long time.
l Constantly check the battery as it may leak when
it has been using for some time, replace the
battery as soon as leaking appears. A leaking
battery will damage the Meter.
Model UT50E: OPERATING MANUAL
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International Electrical Symbols
AC (Alternating Current).
DC (Direct Current).
AC or DC.
Grounding.
Double Insulated.
Deficiency of Built-In Battery.
Continuity Test.
Diode.
Fuse.
Warning. Refer to the Operating Manual.
Conforms to Standards of European Union.
Model UT50E: OPERATING MANUAL
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The multimeter Structure (see figure 1)
9
( figure 1)
1LCD Display
2Data Hold Button.
3Rotary Switch
4Power
5COM Input Terminal
620A Input Terminal
7mA Input Terminal
8V oCInput Terminal
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Functional Buttons
Below table indicated for information about the functional
button operations
Button Operation Performed
HOLD
(Blue Button)
POWER
(Yellow Button)
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Display Symbols (see figure 2)
( figure 2)
No. Symbol Meaning
1Dangerous Voltages.
2The battery is low.
Warning: To avoid false readings,
which could lead to possible electric
shock or personal injury, replace the
battery as soon as the battery
indicator appears.
3Indicator for AC voltage or
current.The displayed value is the
mean value.
4Indicates negative reading.
5Test of diode.
6Data hold is active.
7The continuity buzzer is on.
8Centigrade temperature
oC
oF
9Fahrenheit temperature
µA, mA, A A: Amperes (amps). The unit of
current.
mA: Milliamp. 1 x 10-3 or 0.001
amperes.
µA: Microamp. 1x 10-6 or 0.000001
amperes.
10
V: Volts. The unit of voltage.
mV: Millivolt. 1 x 10-3 or 0.001 volts.
mV, V
11
Model UT50E: OPERATING MANUAL
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Display Symbols (see figure 2)
No. Symbol Meaning
nF, µF
12 F: Farad. The unit of capacitance.
µF: Microfarad.1 x 10-6 or 0.000001
farads.
nF: Nanofarad.1 x 10-9 or 0.000000001
farads.
kHz
13 The unit of frequency in cycles/
second. Kilohertz. 1 x 10-3 or
1,000 hertz.
Ω: Ohm. The unit of resistance.
kΩ: kilohm. 1 x 103or 1000
ohms.
MΩ: Megaohm. 1 x 106or 1,000,000
ohms.
Ω,kΩ,MΩ
14
Model UT50E: OPERATING MANUAL

Measurement Operation(1)
A. DC Voltage Measurement (see figure 3)
Warning
To avoid harms to you or damages to the Meter from
electric shock, please do not attempt to measure
voltages higher than 1000V or 750V rms although
readings may be obtained.
The DC Voltage ranges are: 200mV, 2V, 20V, 200V and
1000V. To measure DC voltage, connect the Meter as
follows:
( figure 3)
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1. Insert the red test lead into the V oC input
terminal and the black test lead into the COM input
terminal.
2. Set the rotary switch to an appropriate measurement
position in V range.
3. Connect the test leads across with the object being
measured.
The measured value shows on the display.
lMake sure the Sleep Mode is not on if you found
there is no display on the LCD after turning on the
Meter.
lMake sure the Low Battery Display is not on, otherwise
false readings may be provided.
lPay extra attention to the symbol which is located
besides the input terminals of the Meter before carrying
out measeurement.
red black
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Measurement Operation(2)
Note
l If the value of voltage to be measured is unknown,
use the maximum measurement position (1000V)
and reduce the range step by step until a satisfactory
reading is obtained.
l The LCD displays “1” indicating the existing selected
range is overloaded, it is required to select a higher
range in order to obtain a correct reading.
l In each range, the Meter has an input impedance of
approx. 10MΩ. This loading effect can cause
measurement errors in high impedance circuits. If
the circuit impedance is less than or equal to 10kΩ,
the error is negligible (0.1% or less).
l When DC voltage measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test.
B. AC Voltage Measurement (see figure 3)
Warning
To avoid harms to you or damages to the Meter from
electric shock, please do not attempt to measure
voltages higher than 1000V or 750V rms although
readings may be obtained.
red black
( figure 3)
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The AC voltage measurement has 4 measurement
positions on the rotary switch: 2V, 20V, 200V and 750V
To measure AC Voltage, connect the Meter as follows:
1. Insert the red test lead into the VΩoC terminal
and the black test lead into the COM terminal.
2. Set the rotary switch to an appropriate measurement
position in V range.
3. Connect the test leads across with the object being
measured.
The measured value shows on the display, which is
effective value of sine wave (mean value response).
Note
l If the value of voltage to be measured is unknown,
use the maximum measurement position (750V) and
reduce the range step by step until a satisfactory
reading is obtained.
l The LCD displays “1” indicating the existing selected
range is overloaded, it is required to select a higher
range in order to obtain a correct reading.
l When AC voltage measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test.
Measurement Operation(3)
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Measurement Operation(4)
C. DC Current Measurement (see figure 4)
Warning
Never attempt an in-circuit current measurement
where the open circuit voltage between terminals
and ground is greater than 60V DC or 30V rms.
If the fuse burns out during measurement, the Meter
may be damaged or the operator himself may be
hurt. Use proper terminals, function, and range for
the measurement. When the testing leads are
connected to the current terminals, do not parallel
them across any circuit.
The DC current measurement has 4 measurement positions
on the rotary switch: 2mA, 20mA, 200mA and 20A.
To measure current, do the following:
1. Turn off power to the circuit. Discharge all high-
voltage capacitors.
2. Insert the red test lead into the mA or 20A terminal
and the black test lead into the COM terminal.
3. Set the rotary switch to an appropriate measurement
position in A range.
4. Break the current path to be tested. Connect the red
test lead to the more positive side of the break and
the black test lead to the more negative side of the
break.
5. Turn on power to the circuit.
The measured value shows on the display.
( figure 4)
red
black
Model UT50E: OPERATING MANUAL

Measurement Operation(5)
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Note
l If the value of current to be measured is unknown,
use the maximum measurement position (20A) and
20A terminal, and reduce the range step by step
until a satisfactory reading is obtained.
l When current measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test.
D. AC Current Measurement (see figure 4)
( figure 4)
Warning
Never attempt an in-circuit current measurement
where the voltage between terminals and ground is
greaterthan60V.
If the fuse burns out during measurement, the Meter
may be damaged or the operator himself may be hurt.
Use proper terminals, function, and range for the
measurement. When the testing leads are connected
tothecurrentterminals,donotparallelthem across any circuit.
The AC current measurement has 3 measurement
positions on the rotary switch: 20mA, 200mA and 20A.
To measure current, do the following:
1. Turn off power to the circuit. Discharge all high-
voltage capacitors.
2. Insert the red test lead into the mA or 20A terminal
and the black test lead into the COM terminal.
red
black
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Measurement Operation(6)
3. Set the rotary switch to an appropriate measurement
position in Arange.
4. Break the current path to be tested. Connect the red
test lead to the more positive side of the break and
the black test lead to the more negative side of the
break.
5. Turn on power to the circuit.
The measured value shows on the display.
Note
l If the value of current to be measured is unknown,
use the maximum measurement position (20A) and
20A terminal and reduce the range step by step until
a satisfactory reading is obtained.
l When current measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test.
E. Measuring Resistance (see figure 5)
( figure 5)
red black
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Warning
To avoid damages to the Meter or to the devices under
test, disconnect circuit power and discharge all the
high-voltage capacitors before measuring resistance.
The resistance ranges has 7 measurement positions on
the rotary switch: 200Ω, 2kΩ, 20kΩ, 200kΩ, 2MΩ,
20MΩand 200MΩ .
Note
l The test leads can add 0.1Ωto 0.3Ωof error to the
resistance measurement. To obtain precision readings
in low-resistance, that is the range of 200Ω, short-circuit
the input terminals beforehand and record the reading
obtained (called this reading as X). (X) is the additional
resistance from the test lead.
Then use the equation:
measured resistance value (Y) – (X) = precision
readings of resistance.
l For high resistance (>1MΩ), it is normal taking several
seconds to obtain a stable reading.
l When there is no input, for example in open circuit
condition, the Meter displays “1”.
When resistance measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test.
Measurement Operation(7)
To measure resistance, connect the Meter as follows:
1. Insert the red test lead into the VΩoCterminal and
the black test lead into the COM terminal.
2. Set the rotary switch to an appropriate measurement
position inΩrange.
3. Connect the test leads across with the object being
measured.
The measured value shows on the display.
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Measurement Operation(8)
Warning
To avoid damage to the Meter or to the equipment
under test, disconnect circuit power and discharge
all high-voltage capacitors before measuring diodes
and continuity.
Testing Diodes
Use the diode test to check diodes, transistors, and other
semiconductor devices. The diode test sends a current
through the semiconductor junction, and then measures
the voltage drop across the junction. A good silicon
junction drops between 0.5V and 0.8V.
To test out a diode out of a circuit, connect the Meter as
follows:
1. Insert the red test lead into the VoCterminal and
the black test lead into the COM terminal.
2. Set the rotary switch to .
F. Measuring Diodes & Continuity (see figure 6)
( figure 6)
red black
Model UT50E: OPERATING MANUAL