KYORITSU kew 4300 User manual

Instruction Manual
Simplified Earth Tester
KEW 4300

Contents
1. Safety warnings･････････････････････････････････････････ 1
2. Features･･･････････････････････････････････････････････ 4
3. Specification････････････････････････････････････････････ 5
4. Instrument layout････････････････････････････････････････ 8
5. Accessories････････････････････････････････････････････ 10
6. Getting started･････････････････････････････････････････ 11
6-1 Battery voltage check･･･････････････････････････････ 11
6-2 Attaching Metal tip/ adapter･･････････････････････････ 11
7. Voltage measurement･･･････････････････････････････････ 13
7-1 Measurement procedure･････････････････････････････ 13
7-2 Live circuit warning･････････････････････････････････ 14
8. Earth resistance measurement･･･････････････････････････ 15
8-1 Principle of measurement････････････････････････････ 15
8-2 Measurement procedure･････････････････････････････ 16
9. LCD backlight and LED light･････････････････････････････ 18
10. Replacing batteries････････････････････････････････････ 19

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1. Safety warnings
This instrument has been designed, manufactured and tested
according to IEC 61010-1: Safety requirements for Electronic
measuring apparatus, and delivered in the best condition after
passing quality control tests.
This instruction manual contains warnings and safety rules which
have to be observed by the user to ensure safe operation of the
instrument and to maintain it in safe condition. Therefore, read
through these operating instructions before using the instrument.
#DANGER
● Read through and understand the instructions contained in this
manual before using the instrument.
● Keep the manual at hand to enable quick reference whenever
necessary.
● The instrument is to be used only in its intended applications.
● Understand and follow all the safety instructions contained in
the manual.
It is essential that the above instructions are adhered to. Failure
to follow the above instructions may cause injury, instrument
damage and/or damage to equipment under test.
The symbol #indicated on the instrument, means that the user
must refer to the related parts in the manual for safe operation of
the instrument. It is essential to read the instructions wherever the
#symbol appears in the manual.
#DANGER : is reserved for conditions and actions that are
likely to cause serious or fatal injury.
#WARNING : is reserved for conditions and actions that can
cause serious or fatal injury.
#CAUTION : is reserved for conditions and actions that can
cause injury or instrument damage.

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#DANGER
● Never make measurement on a circuit in which the electrical
potential exceeds 300V.
● Do not attempt to make measurement in the presence of
flammable gasses. Otherwise, the use of the instrument may
cause sparking, which can lead to an explosion.
● Never attempt to use the instrument if its surface or your hand
is wet.
● Be careful not to short-circuit the power line with the metal
part of the test leads when measuring voltage. It may cause
personal injury.
● Do not exceed the maximum allowable input of any
measurement range.
●
Never open the Battery compartment cover during a measurement.
#WARNING
● Never attempt to make any measurement if any abnormal
conditions, such as a broken cover or exposed metal parts are
present on the instrument and test leads.
● Do not press the Test button when connecting the test leads to
the instrument.
● Do not install substitute parts or make any modification to
the instrument. Return the instrument to your local Kyoritsu
distributor for repair or re-calibration in case of suspected faulty
operation.
● Do not replace batteries if the instrument is wet.
● Ensure that the L-shaped Banana plug of MODEL7248 is firmly
inserted into the E terminal.
● Powe r off the ins trume nt wh en opening th e Batt ery
compartment cover for battery replacement.
#CAUTION
● Ensure that the instrument is powered off after use and test
leads are disconnected. Remove the batteries if the instrument
is to be stored and will not be in use for a long period.
● Do not expose the instrument to direct sunlight, high
temperature, humidity or dew.
● Use a damp cloth with neutral detergent or water for cleaning
the instrument. Do not use abrasives or solvents.
● Do not store the instrument if it is wet.

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Symbols
CAT.III
Primary electrical circuits of the equipment connected
directly to the distribution panel, and feeders from the
distribution panel to outlets.
Instrument with double or reinforced insulation
#User must refer to the explanations in the instruction
manual.
(Functional) Earth terminal
Crossed-out wheel bin symbol (according to WEEE
Directive: 2002/96/EC) indicating that this electrical
product may not be treated as household waste, but
that it must be collected and treated separately.
○ Measurement (over-voltage) category
To ensure safe operation of measuring instruments, IEC 61010
establishes safety standards for various electrical environments,
categorized as CAT.I to CAT.IV, and called measurement categories.
Higher-numbered categories correspond to electrical environments
with greater momentary energy, so a measuring instrument
designed for CAT.III environments can endure greater momentary
energy than one designed for CAT.II.
CAT.I : Secondary electrical circuits connected to an AC
electrical outlet through a transformer or similar device.
CAT.II : Primary electrical circuits of equipment connected to an
AC electrical outlet by a power cord.
CAT.III : Primary electrical circuits of the equipment connected
directly to the distribution panel, and feeders from the
distribution panel to outlets.
CAT.IV : The circuit from the service drop to the service entrance,
and to the power meter and primary overcurrent
protection device (distribution panel).
Transformer

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2. Features
KEW4300 is a simplified earth resistance tester (based on 2-pole
method) that can be used for various distribution lines and electrical
appliances and it also can measure AC/DC voltages. (As for AC
voltages, true rms values can be obtained.)
● Designed to meet the following safety standards
IEC 61010-1 CAT.III 300V, Pollution degree 2
IEC 61010-031
IEC 61557-1, 5
● 200/ 2000Ω (2 ranges) : auto-ranging
● Warning buzzer triggered at 100Ω or less
● LED lights up when a large earth voltage is detected.
● Small test current (max 2mA) not triggering ELB
● Live circuit warning when 30V or higher voltage is detected.
(KEW4300 detects voltage even when measuring resistances.)
● LED light for illuminating measurement points
(It turns on/off automatically in relation to the ambient brightness.)
● Backlight working in conjunction with the LED light
● Glow in the dark button
● User-friendly and compact design
● Auto-power-off function is also available to power off the
instrument when 10 min pass after the last operation. This
function does not work while a continuous measurement is
performed.
● Strap for prevent drop
● User replaceable metal tips are supplied as standard accessories

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3. Specification
● Measurement range and accuracy (23ºC±5Cº, relative humidity
75% or less)
Voltage/ Earth voltage measurement
Measurement range Display range Accuracy
AC5.0 to 300.0V
(45 to 65Hz)
(425V peak or less)
0.0 to 314.9V ±1%rdg±4dgt
DC±5.0 to ±300.0V 0.0 to ±314.9V ±1%rdg±8dgt
*AC measurement method : rms detection
For the waveforms other than sinewave
of CF<2.5, the specified accuracy
±1%f.s. should be applied.
* AC/DC auto-detection at 5V or higher
* DC sign appears at 5V or higher.
(H+S(C+P) terminal: positive side, E terminal : negative side)
* The LCD reads 0.0V for 0.9V or lower voltages.
Earth resistance measurement
Range
(auto-ranging)
Measurement
range Display range Accuracy
200Ω Range 5.0 to 2000Ω 0.0 to 209.9Ω ±3%rdg±5dgt
2000Ω Range 160 to 2099Ω
Measurement method:Constant current inverter
approx. 1.4mA (200Ω Range)/825Hz
approx. 0.7mA (2000Ω Range)/825Hz
Open voltage: Approx. 13V

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● Applicable
standards
● IEC 61010-1
● IEC 60529(IP40)
● IEC 61557-1, -5
● IEC 61326-1, 2-2
● IEC 61010-031
MODEL7248 / CAT.III600V
(Alligator clip should be attached and used
in the CAT. III or higher environment.)
MODEL8253 / CAT.III300V
(while it is connected to the instrument)
* When the test leads are connected to the
instrument, the lower category either of
them belongs to is applied.
● Location for use Altitude 2000m or less, indoor use
● LCD Segment display with backlight
● Operating
temperature and
humidity range
-10ºC to 50ºC,
80% or less (no condensation)
● Storage
temperature and
humidity range
-20ºC to 60ºC,
75% or less (no condensation)
● Withstand
voltage
AC3,540V(50/60Hz)/ for 5 sec between the
electrical circuit and the enclosure
● Insulation
resistance
50MΩ or more/ DC1000V between the
electrical circuit and the enclosure
● Auto-power-off
function
Auto-power-off function operates with audible
warning and powers off the instrument when
approx 10min pass after the last operation.
(This function is disabled during a resistance
measurement.)
● Backlight Turns off automatically when approx 2min
pass after the last operation. (This function is
disabled during a measurement.)
● Dimensions 232(L) x 51(W) x 42(D)mm
(including the metal tip)
● Weight Approx. 220g (including batteries)
● Power source Size AA, alkaline battery x 2pcs
(The use of alkaline LR6 is recommended.)

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● Operating Error
Operating error (B) is an error obtained within the rated operating
conditions, and calculated with the intrinsic error (A), which is an
error of the instrument used, and the error (Ei) due to variations.
According to IEC61557, the maximum operating error should be
within ±30%.
● Operating error at earth resistance measurements (IEC61557-5)
Formula: B= ±(|A|+1.15 x √E2
2+E3 2+E4 2)
A Reference condition
E1Normal operating position ±90º
E2Variation due to changing the supply voltage (until the
Battery symbol appears)
E3Variation due to changing the temperature
(-10ºC to 50ºC)
E4Variation due to series interference voltage
16•2/3Hz, 50Hz, 60Hz, DC: 10V
400Hz: 3V
E5Variation due to resistance of the probes and auxiliary
earth electrode resistance
E1: It is not applicable to digital testers.
E5: It is not applicable to simplified earth testers.
Measurement range within which the maximum operating error
±30% applies: 5.00Ω to 2000Ω.
● Number of measurement
(measuring for 5 sec and take a pause for 25 sec)
Function Resistor
for test
Number of measurement
(within effective battery voltage
range)
Earth measurement 10Ω Approx. 3000 times

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4. Instrument layout
(1) Instrument Body
Name Details
1
H+S(C+P) terminal
To connect the replaceable metal tip MODEL8072
has been installed and delivered.
2 LED light
To illuminate the measurement spots
The light turns on/off automatically in relation to
ambient brightness.
3 Ambient light sensor
To sense ambient brightness for turning on/ off
the light
4 Test button
To conduct resistance measurement
Measurement is conducted when the button is held
down.
5 Warning LED To give warnings for live circuit (blinking red)
and for large earth voltage (blinking yellow)
6 LCD
LCD with backlight
The backlight turns on/off automatically in relation
to ambient brightness.
7 Power button To power on/ off the instrument.
The button should be held down for 1 sec or longer.
8 E terminal To connect the test lead MODEL7248
5 6
347
2
18
Fig. 4-1

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(2) LCD
● Symbols displayed on the LCD
Indicate the batteries need to replace.
Show the measured results.
Appear when the measured result exceeds the display
range.
Resistance : >2099Ω
Voltage :
> 314.9V (“-OL” for negative DC voltages)
Indicate the end of a measurement with frozen
measured result.
Blink to give a warning for live circuit
● Symbol displayed at earth measurements
A unit of earth resistance
● Symbols at voltage/ earth voltage measurements
・“AC” for alternate voltages and “DC” for direct voltages
A unit of voltage
Polarity sign for negative voltages
Fig. 4-2

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5. Accessories
● Test leads
(1) MODEL7248 – with Alligator clip and Flat test bar
(2) Banana plug, both ends, black
＋
(3) Alligator clip (4) Flat test bar
＋
● Tip metal tips for H+S(C+P) terminal
(1) MODEL8072
Standard metal tip
installed at a shipment.
(2) MODEL8253 (3) MODEL8017
Metal tip with plastic molded
Long type and helpful to access
the distant measurement spot
● Others
(1) Carrying case
(2) Strap
(3) Size AA alkaline battery x 2 pcs
(4) Instruction manual
Fig.5-2
Fig. 5-4
Fig. 5-5 Fig. 5-6
Fig. 5-3
Fig. 5-1
L-shaped
Bananaplug

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6. Getting started
6-1 Battery voltage check
(1) Please refer to “10. Replacing batteries” in this manual and
insert batteries in KEW4300.
(2) Hold down the Power button at least 1 sec and power on
KEW4300.
* A long press of 1 sec or longer is required to power on/ off the
instrument. It is to prevent a malfunction.
(3)
The battery voltage is extremely low when the “ “ symbol
appears at the upper left corner on the LCD. Replace the
batteries with reference to “10. Replacing batteries” to carry out
further measurements.
The use of size AA alkaline battery is recommended. The Battery
symbol may not appear correctly when the other types of batteries
are used.
6-2 Attaching metal tip/ adapter
The metal tip for the H+S(C+P) terminal and the adapters for
MODEL7248 to be connected to the E terminal are replaceable
depending on applications.
#DANGER
Always attach and use the M-8253 and the Alligator clip to use
this instrument in the CAT.III or higher environments. The other
metal tips: M-8072, M-8017 and the Flat test bar have a large
exposed metal and may short the equipment under test. It may
cause a malfunction of the equipment under test, a fire or fatal/
serious injuries to the user or the people around.
(1) Replaceable metal tip
The metal tips are replaceable depending on applications.
[Available tip metal tips]
1. MODEL8072 : Standard metal tip installed at a shipment
2. MODEL8253 : Metal tip with plastic molded
3. MODEL8017 : Long type and helpful to access the distant
measurement spot

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[How to replace the parts]
Detach the metal tip by turning the red plastic parts counter
clockwise.
Install the metal tip you want to use into the hexagon hole, and
turn the red plastic parts clockwise to tighten firmly.
(2) Test leads
Either of the following adapters should be connected to the cord
with Banana plug, both ends.
[Adapters for MODEL7248]
1. Alligator clip
2. Flat test bar
[How to connect]
Firmly insert and connect the adapter to the end of the cord with
Banana plug, both ends.
#DANGER
To avoid getting electrical shocks, ensure that test leads are
disconnected from the instrument when replacing the metal tip or
adapter for test leads.
メネジ
六角穴
先端金具
Internal
thread
Hexagon
hole
Metal tip
MODEL 8253
MODEL 8072
MODEL 8017
Alligator clip
Flat test bar
Banana plug, both ends
Fig. 6-1
Fig. 6-2

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7. Voltage measurement
#DANGER
● Never apply voltages exceeding 300V, max over-voltage
protection, to this instrument.
7-1 Measurement procedure
(1) Connect the test leads to the instrument.
Plug the L-shaped Banana plug of MODEL7248 into the E
terminal as illustrated below.
(2) Connect the adapter for test leads to the earth side of the circuit
under test and the metal tip (H+S(C+P) terminal) to the line side
respectively. Connecting that in reverse is also fine if the circuit
under test is not earthed.
Caution
Do not press
the Test button.
Fig. 7-1
Fig. 7-2

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(3) The measured voltage is displayed on the LCD.
Take the reading without pressing the Test button. The
instrument judges DC or AC and shows “DC” or “AC” sign on the
LCD.
* When negative DC voltages are detected at the H+S(C+P)
terminal, the negative polarity sign “-“ appears to the left of the
measured value.
* The LCD does not show “DC”, “AC” nor sign when the
measured values are less than 5V.
The LCD shows “>314.9V” when the measured value exceeds
the display range (over range) and it shows “-OL” for negative DC
voltages.
7-2 Live circuit warning
The warning LED starts blinking red with audible warning when the
measured value is 30V or higher.
* The instrument does not carry out resistance measurements
even the Test button is held down while the live circuit warning is
activating.
LED starts blinking. (Red)
Fig.7-3

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8. Earth resistance measurement
This instrument can measure the earth resistances of distribution
line, internal wiring and electrical appliance.
#DANGER
● Never apply inputs exceeding 300V between the measuring
terminals at earth voltage measurements.
● No voltage should be applied between the measuring terminals
during earth resistance measurements.
8-1 Principle of measurement
This instrument carries out earth resistance measurements based
on the fall-of-potential method. This is a simplified earth resistance
tester and uses the existing earth systems (with a sufficiently
low earth resistance) such as buried metal pipes like main water
pipe, common earth for commercial power supply and a lightning
electrode on buildings and performs measurements based on the
2-pole measurement method.
The AC constant current
“I” is applied between the
measurement object “Rx”
(earth electrode) and the
existing electrode “re” to
obtain the earth resistance
value “Rx + re” and find out
the voltage “V” between the
E and H+S(C+P) terminals.
See Fig. 8-1.
Rx + re = V / I
The resistance “re” of the existing earth electrode with which
H+S(C+P) terminal is connected is added to the true resistance
“Rx” of the measured object, and displayed as the measured result.
Re (measured value) = Rx + re
If the value of “re” is already known, deduct it from the measured
value “Re” to determine “Rx” value.
Rx (true resistance value) = Re – re
H+S(C+P)
terminal
E
terminal
Voltmeter
Earthingsystem
undertest
Earthelectrode
Constantcurrent
generator
Secondary Primary
I→
Fig.8-1

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8-2 Measurement procedure
(1) Connect the test leads to the instrument.
Plug the L-shaped Banana plug of MODEL7248 into the E
terminal as illustrated below.
(2) Connection
Connect the instrument as illustrated below.
#DANGER
● Always use a voltage detector for testing the earth side of the
commercial power supply.
● Do not use this instrument for testing the earth side of the
commercial power supply. It is dangerous because the LCD
may not show the measured voltage even the circuit under
test is in live if the earth of the electrode under test is loose/
disconnected or the connection of the test leads is not proper.
(3) Checking the earth voltage
Check the earth voltage displayed on the LCD without pressing
the Test button.
Fig.8-2
Fig.8-3Measuring the earth resistance
ofload Fig.8-4Me a s uri n g t h e ear t h resistanceofwallsocket
H+S(C+P)
E
Rx
re
POWER LOAD L
N
E

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● The displayed value should be less than 10V.
The warning LED starts blinking yellow when the earth voltage
is 10V or higher. (The LED starts blinking at 3V or higher if the
frequency of the earth voltage is 400Hz.)
Ensue that the systems connected to the earth electrode under
test are turned off to get the earth voltages lower when the
warning LED for earth voltage starts blinking. Otherwise, accurate
measured results can not be obtained. The warning LED for earth
voltage may not light up if the frequency is over 400Hz.
● The warning LED starts blinking red with audible warning when
the voltage of 30V or higher is detected. Earth resistance
measurements can not be carried out by pressing the Test
button while the live circuit warning is activating.
(4) Measurement
Press the Test button. The LCD shows the measured result.
The instrument carries out an earth resistance measurement
while the Test button is held down. The buzzer sounds when the
measured value is less than 100Ω.
The measurement is halted when the Test button is released,
and the measured data freezes on the LCD. (The “ ” symbol
appears on the LCD.) A short press of the Test button while the
result is being displayed on the LCD gets the instrument entered
into the Voltage measurement mode.
● The LCD shows “>2099Ω” when the measured result exceeds
the display range. (Over range)
● The instrument automatically enters into the voltage
measurement mode when sensing the live circuit during a
resistance measurement and activates the warning function.
● If an earth resistance measurement is continued at low battery
level with Battery symbol on the LCD, the instrument may be
powered off suddenly.
LED starts blinking.
10V or higher: yellow
30V or higher: red
Fig.8-5

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9. LCD backlight and LED light
The LCD backlight and the LED light on this instrument turn on/off
automatically in relation to ambient brightness. These lights keep
on for about 15 sec once they turn on. The Ambient light sensor as
shown in the below figure senses the ambient brightness.
● Dirt on the surface of the sensor may interfere the proper
operation of the lights. Keep the sensor clean.
● The sensitivity of the sensor is not adjustable. Cover the sensor
with your hand or finger if you need to turn on the lights. The
lights keep on for about 15 sec once they turn on.
[Turning off the Auto-light mode]
The following procedure is for setting the lights always off.
1. Ensure that the instrument is powered off.
2. Hold down the Power button for 1 sec while the Test button is
held down and power on the instrument.
3. Now the Auto-light mode is disabled. Repeating above steps
1.& 2. restores the mode.
The number of beep when powering on the
instrument is different depending on the
selected light mode. The selected mode
will not be reset even after powering off the
instrument.
Number of beep Light mode
Once Auto
Twice Always off
Ambient light sensor
Buzzer sounds
when powering on
the instrument.
Pi･･･
Fig.9-1
Fig.9-2