KYORITSU KEW 2413R User manual

KEW SNAP Series
KEW 2413R
DIGITAL CLAMP METER
KYORITSU ELECTRICAL INSTRUMENTS
WORKS，LTD.
INSTRUCTION MANUAL

Contents
１．Safety Warnings ………………………………………………………１
２．Features ………………………………………………………………４
３．Specifications …………………………………………………………５
４．Instrument Layout ……………………………………………………９
５．Operation
５-１ Preparation ……………………………………………………11
５-２ AC Current Measurement ……………………………………11
５-３ How to Use Peak Hold Function ……………………………14
５-４ How to Use The Frequency Selector Switch ………………16
５-５ How to Use Data Hold Function ………………………………17
５-６ How to use Back Light …………………………………………17
５-７ Analogue Output How to Use Model 7073 Output Cord ……18
６．Battery Replacement …………………………………………………19
７．Cleaning ………………………………………………………………20
８．Before Sending For Repair …………………………………………21

— 1 —
１．Safety Warnings
This instrument has been designed and tested according to IEC
Publication 61010: Safety Requirements for Electronic Measuring
Apparatus. This instruction manual contains warnings and safety rules
which must be observed by the user to ensure safe operation of the
instrument and retain it in safe condition. Therefore, read through these
operating instructions before starting using the instrument.
●The symbol
#
indicated on the instrument means that the user must
refer to related parts in the manual for safe operation of the
instrument. Be sure to carefully read the instruction following each
#
symbol in this 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 bodily injury or instrument damage.
#
WARNING
●Read through and understand instructions contained in this
manual before starting using the instrument.
●Save and keep the manual handy 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.
Failure to follow the instructions may cause injury, instrument
damage and/or damage to equipment under test. Kyoritsu is by
no means liable for any damage resulting from the instrument in
contradiction to this cautionary note.

— 2 —
Following symbols are used on the instrument and in the instruction
manual. Attention should be paid to each symbol to ensure your safety.
#Refer to the instructions in the manual.
This symbol is marked where the user must refer to the instruction
manual so as not to cause personal injury or instrument damage.
Indicates an instrument with double or reinforced insulation.
Indicates that this instrument can clamp on bare conductors when
measuring a voltage corresponding to the applicable Measurement
category, which is marked next to this symbol.
This instrument satisfies the marking requirement defined in the
WEEE Directive (2002/96/EC). This symbol indicates separate
collection for electrical and electronic equipment.
#
DANGER
●Never make measurement on a circuit above 300V AC (CAT. Ⅲ).
● Do not attempt to make measurement in the presence of
flammable gasses, fumes, vapor or dust. Otherwise, the use of the
instrument may cause sparking, which can lead to an explosion.
●Transformer jaw tips are designed not to short the circuit under
test. If equipment under test has exposed conductive parts,
however, extra precaution should be taken to minimize the
possibility of shorting.
● Never open the battery compartment cover when making measurement.
● Never attempt to use the instrument if its surface or your hand is wet.
● Do not exceed the maximum allowable input of any measurement range.
●Never try to make measurement if any abnormal conditions, such
as broken Transformer jaws or case is noted.
●The instrument is be used only in its intended applications or
conditions. Otherwise,Safety functions equipped with the
instrument doesn't work, and instrument damage or serious
personal injury may be caused.
● Keep your fingers and hands behind the barrier during measurement.
#
WARNING
●Never attempt to make any measurement if any abnormal
conditions are noted, such as broken case, cracked test leads
and exposed metal parts.
●Do not install substitute parts or make any modification to the
instrument. Return the instrument to Kyoritsu or your distributor
for repair or re-calibration.
●Do not try to replace the battery if the surface of the instrument is wet.

— 3 —
#
CAUTION
●Do not expose the instrument to the direct sun, extreme
temperatures or dew fall.
●Be sure to set the function selector switch to the “OFF”position
after use. When the instrument will not be use for a long period of
time, place it in storage after removing the battery.
This is to avoid damage to the instrument by possible leakage
from the battery.
●Use a damp cloth and detergent for cleaning the instrument. Do
not use abrasives or solvents.
●This instrument isn't dust & water proofed. Keep away from dust
and water.
●Never apply voltage to the OUTPUT terminal. the terminal is not
electrically isolated from the internal circuits of the instrument.
Measurement categories (Over-voltage categories)
To ensure safe operation of measuring instruments, IEC 61010
establishes safety standards for various electrical environments,
categorized as O 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.
O : Circuits which are not directly connected to the mains
power supply.
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).
O: Device which is
not directly
connected to the
mains power supply

— 4 —
２．Features
KEW 2413R is a unique digital clamp meter for both very low current
and high current measurements. Its shielded transformers jaws
minimizes the effect of external stray magnetic field, enabling leakage
current measurements.
●Measures from 0.1mA to 1000A AC and provides frequency response
higher than 1kHz on all measuring ranges.
Measurements also possible with approximately -7% accuracy at 20
kHz on 200mA range.
●Provides a frequency selector switch —50/60Hz or WIDE —to turn
on or off an incorporated low pass filter. This permits current
measurement in mains fundamental frequency only or a wide range
of frequencies, including those from such devices as inverters.
●Peak-hold facility with selectable response time of 10ms or 100 ms.
●Two-way analogue output terminal
Provides AC voltage output proportional to the current under test for
monitoring the waveform with an oscilloscope.
Also convent AC current readings to DC voltage output for direct
connection to such devices as a chart recorder.
●Data hold function to allow for easy readings in hard-to-reach
locations. Display can be observed away from the conductor.
●LCD Back Light function to facilitate working at dimly lit situations.

— 5 —
３．Specifications
Measuring Ranges and Accuracy
● AC Current
Ranges
200mＡ
2Ａ
20Ａ
200Ａ
1000Ａ
0〜199.9mA
CF≦3.0
0〜1.999A
CF≦3.0
0〜19.99A
CF≦3.0
0〜199.9A
CF≦3.0
0〜500A
CF≦3.0
501〜1000A
CF≦3.0
Accuracy
Frequency Range Response
50/60Hz
* only sine wave
WIDE
* Add 2% at CF ≧ 2
±1.8％rdg±5dgt (50／60Hz)
±3.0％rdg±5dgt (40〜1kHz)
±2.0％rdg±5dgt (50／60Hz)
±3.5％rdg±5dgt (40〜1kHz)
±5.0％rdg (50／60Hz)
±3.0％rdg±5dgt
± 5.5％ rdg
10min.
Time Limit for
Measurements
Continuous
● Effective Value (RMS)
Most alternating currents and voltages are expressed in effective
values, which are also referred to as RMS (Root-Mean-Square) values.
The effective value is the square root of the average of square of
alternating current or voltage values. Many clamp meters using a
conventional rectifying circuit have "RMS" scales for AC measurement.
The scales are, however, actually calibrated in terms of the effective
value of a sine wave though the clamp meter is responding to the
average value. The calibration is done with a conversion factor of 1.111
for sine wave, which is found by dividing the effective value by the
average value. These instruments are therefore in error if the input
voltage or current has some other shape than sine wave.
● CF (Crest Factor) is found by dividing the peak value by the effective value.
Examples: Sine wave: CF=1.414
Square wave with a 1: 9 duty ratio: CF=3

— 6 —

— 7 —
Range
200mA
2A
20A
200A
1000A
Measuring Range
0〜200mA
0〜2A
0〜20A
0〜200A
0〜500A
501A〜1000A
AC Output Voltage Accuracy
0〜200mV
±2.0％rdg±0.5mV
±2.5％rdg±0.5mV
±3.0％rdg±0.5mV
±5.0％rdg±0.5mV
0〜50mV
50〜100mV
Analogue Output (Output impedance: Approx. 1k Ω )
● AC Output
*Voltage proportional to the current under test is output with
“WIDE”frequency characteristics regardless of the setting of the
frequency Selector or peak hold switch.
● DC Output
*DC voltage is output in proportion to the display reading, which
reflects frequency selector or peak hold switch position −200mV
DC for 2000 count reading.
200mA
2A
20A
200A
1000A
0〜200mA
0〜2A
0〜20A
0〜200A
0〜500A
501A〜1000A
Ranges
AC Input
Current
DC Output
Voltage
Accuracy (Frequency Range)
Freq. Selector
Switch at
WIDE position
Freq. Selector
Switch at 50/60Hz
position
0 〜 200mV
±3.0％rdg±0.5mV
±3.5％rdg±0.5mV
±5.0％rdg±0.5mV
±7.0％rdg±0.5mV
± 3.5 ％ rdg ± 0.5mV
± 4.0 ％ rdg ± 0.5mV
± 5.5
％ rdg ± 0.5mV
± 7.5
％ rdg ± 0.5mV
0 〜 50mV
50〜100mV

— 8 —
Operating System ：Dual Integration
Display ：Field effect 3・1/2 digit liquid crystal
display with maximum count of 1999
Range selection ：Manual
Overrange Indication ： “ 1”is displayed on the highest digit
except for 1000A AC range.
Response Time ：Approx. 3 seconds
Sample Rate ：Approx. 3 times per second
Data Hold ：Available on all ranges
Location for use ：Indoor use, Altitude up to 2000m
Temperature ＆ Humidity ：23℃
± ５℃ , relative humidity up to 85%
for Specified Accuracy without condensation
Storage Temperature ：-20〜60℃, relative humidity up to 80%
& Humidity without condensation
Operating Temperature ：0 〜40℃,relative humidity up to 85%
& Humidity without condensation
Power Source ：One 6 F22 or equivalent battery
Low Battery Warning ：
“ ” symbol is shown on the display.
Current Consumption ： Approx. 5mA max.(use Back Light:8mA max.)
Standard(Safety) ：IEC61010-1
IEC61010-2-032
CAT Ⅲ,AC300V,Pollution degree 2
(EMC) ：IEC61326-1
Environmental Standards ：EU RoHS Directive compliant
Overload Protection ：1500A AC max for 1 minute
Withstand Voltage ：
3470V AC for 5 seconds between electrical
circuit and housing cases
Insulation Resistance ：50M Ωor greater at 1000V between
electrical circuits and housing cases or
metal parts of jaws
Conductor Size ：Approx. 68mm diameter max.
Dimensions/Weight ：250(L)
× 130(W) × 50(D)mm.
Approx. 600g (including battery)
Accessories ：6F22 battery
Carrying case
Instruction manual
Optional Accessories ：Model 7073 two-way output cord
Peak Hold ：Response time selectable from approx.
10ms and 100ms.
1/ √2 of the peak current is displayed,
which means an RMS reading will be
obtained when current having sinusoidal
waveform in measured.
Peak hold reading varies by approximately
± 1% max of full scale in the first minute at
23℃
± ５ ℃and relative humidity of 75%
without condensation.

— 9 —
① LCD
Field effect liquid crystal display with maximum indication of 1999.
Function symbol(mA, A) and decimal point automatically appear as
the function / range switch is turned.
４．Instrument Layout
over range indication
LCD
①
②
⑨
⑪
⑩
⑦
⑥
⑤
⑧
④
③
Fig.2

— 10 —
“ ” is displayed on the lower right side for low battery warning
and “1”is displayed only at the highest digit for overrange
indication.
② Data Hold Button
Allows for easy reading in dimly lit or hard-to-reach-locations. The
display can be observed away from the conductor after pushing in
the button. Data hold can be released by pushing the button again
after the reading is taken. Symbol “”is displayed on the LCD.
③ Two-way Analogue Output Terminal
AC current picked up by transformer jaws ⑦is converted and
output as AC and DC voltage output. (See Analogue Output in
section 3, Specifications.) Insert output cord Model 7073 into this
terminal for monitoring waveform with an oscilloscope or
connecting to a recorder.
④ Safety Hand Strap
Prevents the instrument from slipping off the hand during use.
⑤ Power Function/Range Switch
Selection function and range. It is also used to turn power on or off.
#
CAUTION
Always set the Power Function/Range Switch to the OFF position
after use.
⑥ Jaw Trigger
Operates transformer jaws ⑦. Press to open the jaws.
⑦ Transformer Jaws
Pick up the current flowing through the conductor.
⑧ Peak Hold Selector Switch
Selects 10ms or 100ms response time. Symbol “”is displayed
on the LCD. Set the switch back to the OFF position to release
peak hold or make normal measurements.
⑨ Frequency Selector Switch
Makes frequency response selection. Symbol“ ”or“ ” is
displayed on the LCD.
⑩ Barrier
It is a part providing against electrical shock and ensuring the
minimum required air and creepage distances.
⑪ Back Light Button
When the “Back Light Button”is pressed, the LCD back light will be
on.
It will be automatically off after about 10 seconds.

— 11 —
５．Operation
５- １ Preparation
(1) To Check battery set the function/range switch ⑤To the desired
position. If the display is clear without symbol “ ” showing,
battery voltage is sufficient. If the display blanks or “ ” is
indicated, replace the battery in accordance with the battery
replacement procedures as described in section 6.
Note：“”also appears on the display when the battery
becomes exhausted during use. Replace with a new battery.
(2) Make certain that the data hold button is in the off position −not
pressed down. If a measurement is made with the data hold button
pressed in, the display remains locked irrespective of input.
Symbol “”is displayed on the LCD.
５- ２ AC current Measurement
#
WARNING
●Do not make measurement on a circuit above 300V AC (CAT Ⅲ).
●Transformer jaw tips are designed not to short the circuit under
test. If equipment under test has exposed conductive parts,
however, extra precaution should be taken to minimize the
possibility of shorting.
●Do not make measurement with the battery compartment cover
removed from the instrument.
●Keep your fingers and hands behind the barrier during
measurement.

— 12 —
#
CAUTION
●Transformers jaws , especially their tips, have been precisely
adjusted to obtain maximum accuracy. Take sufficient care to
avoid shock, vibration or excessive force when handing the
instrument.
●When a foreign substance is stick in the jaw tips or they cannot
properly engage, the transformer jaws do not fully close. In such
a case, do not release the jaw trigger suddenly or attempt to
close the transformer jaws by applying external force. Make
sure that the jaws close by themselves after removing the
foreign substance or making them free to move.
●The maximum size of conductor that can be measured is
approx. 68mm in diameter. An accurate measurement cannot be
made on a conductor larger than this, because the transformer
jaws cannot be fully closed.
●Frequency selector switch ⑨is designed to select
the “50/60Hz”and “WIDE”frequency ranges. For further
details, refer to section 5-4 for operation of the frequency
selector switch.
●The transformer jaws may buzz when measuring large current.
This has no effect on the instrument's performance or safety.
(1) Set the function/range switch to the desired position. Do not exceed
the maximum allowable input current for the selected range.
(2) For normal measurement, press the jaw trigger to open the
transformer jaws and clamp onto one conductor only. See Fig.3.
Earth leakage current or small current that flow through a
grounded wire can also be measured by this method. (Fig. 4)
(3) To measure out of balance leakage current, clamp onto all
conductors except a grounded wire. The leakage current measure
will be indication on the display. (Fig.5)

— 13 —
Note：When measuring large current, observe the time limit specified in
section 3, Specifications. Otherwise, the transformers jaws may
overheat, resulting in damage to the instrument.
It may take several tens of seconds to indicate exact zero, but
this is normal.
Even if current is being applied to the instrument till zero is
indicated on the LCD, it doesn't affect the readings.
Fig.3Normal AC Current
Measurements
Fig.4 Earth Leakage Current
Measurements
Single-Phase 2-wire system
(in 3-wire system with neutral
clam
p
onto all 3 wire
)
3-phase 3-wire system.
(in 4-wire system with neutral
clamp onto all 4 wire)
Fig.5Measurements out of balance Leakage

— 14 —
５- ３ How to Use Peak Hold Function
10ms or 100ms response time can be selected for peak hold
measurement. Make selection according to your application needs.
(1) With the transformer jaws clamped onto the conductor under test,
slide the peak hold switch from the OFF position to the desired peak
response time position. Symbol “ ” is displayed on the LCD.
(2) The peak hold display reads 1/ √2 of the peak current value.
Therefore, an RMS reading will be obtained when the current
under test has a sinusoidal waveform.
(3) Slide the peak hold switch back to the OFF position for a reset.
Note 1：KEW 2413R uses an analogue peak hold circuit to ensure a
quick response to input current. Because of the nature of
this circuit, the peak hold reading may gradually fall or, in a
rare case, rise with time. This is likely to be apparent when
the instrument is used in a high temperature and high
humidity environment. Therefore, the instrument will not be
suitable for making peak measurement over an extended
period of time. In case of such a need, connect a recorder to
the instrument via the analogue output terminal.

— 15 —
Note 2：If it is necessary to read the display away from the conductor
in a peak hold measurement, press the data hold switch ②
first and then remove the instrument from the conductor.
Otherwise, the peak hold reading may be higher than the
actual value due to the electrical noise caused by the
opening and closing of the transformer jaws. Press the data
hold switch again for a reset.
(4) Difference between 10ms and 100ms Peak Response Time
The peak hold circuit in this instrument charges the peak-hold
capacitor after rectifying the input waveform. The time for the voltage
of the capacitor to reach its peak value varies according to its
capacitance and the output impedance of the charging circuit. KEW
2413R sets the time for the voltage of the capacitor to reach 90% of
its peak value to 10ms or 100ms by switching between two output
impedances. Refer to Figure 7 for further details.
I
For instance, select the 10ms response time when measuring a surge
current that will occur when a power supply device is switched on. The
100ms response time is recommended for measuring the starting
current of a motor or similar equipment. A stable measurement can be
made on the 100ms second response time setting as the peak hold
circuit does not readily respond to the surge current.

— 16 —
５- ４ How to Use The Frequency Selector Switch
KEW 2413R has a very good frequency response because of the
electromagnetic property of its transformers jaws. Therefore, it
measured, AC current not only of fundamental frequency of 50Hz or
60Hz, but of high frequencies and harmonics superimposed on the
fundamental frequency. To eliminate these superimposed components
and measure only in the fundamental frequency, KEW 2413R has a
Low pass filter circuit, which can be activated by setting the frequency
selector switch to the “50/60Hz”position. When the frequency selector
switch is set to “WIDE”, symbol “ ” is displayed on the LCD.
When the switch is set to “50/60Hz”, symbol “”is displayed on the
LCD.
The Low pass filter has a cut-off frequency of approx. 100Hz and an
attenuation characteristics of approx. -24 dB/octave.
Note：-24dB/octave means that the magnitude of a signal declines by a
factor of 16 when its initial frequency doubles.
The frequency selector switch has the following two positions.
●WIDE(40Hz −over 1kHz):
Covers a wide frequency band from mains supply to high frequencies
generated by such equipment as inverters.
●50/60Hz(40 −Approx.100Hz):
Filters out high frequency components to restrict measurement in
mains frequency band.
Note 3：The peak hold circuit of this instrument may not capture some
signals depending on phases because a half-wave rectifier
circuit is used.
Response characteristics are 10ms/ 100ms. Noises on higher
frequencies caused by inverters may not be captured. Readings
with Peak Hold off might become smaller or zero when
activating the Peak hold function, but this is not a malfunction.

— 17 —
５- ５ How to Use Data Hold Function
Push in the Data Hold button to freeze the reading. This is especially
useful for taking a reading in a dimly lit or hard-to-reach locations. The
display can be observed away from the conductor. Symbol “ ” is
displayed on the LCD. Push the button again to release the reading.
５- ６ How to use Back Light
When the “Back Light Button”is pressed, the LCD back light will be on.
It will be automatically off after about 10 seconds.
Note：Selection with the frequency selector switch dose not apply to AC
output of the two-way analogue output. DC output of the two-way
analogue output reflects the frequency selector switch setting.
Refer to Figure. 1 for frequency characteristics.

— 18 —
KEW 2413R
５- ７ Analogue Output: How to Use Model 7073 Output Cord
AC and DC output can be obtained by inserting optional Model 7073
output cord into the two-way analogue output terminal ③.
AC Output:
Can be monitored by connecting a digital multimeter to analogue output
terminal or observed as a waveform by connecting an oscilloscope.
DC Output:
Can be monitored by connecting a digital multimeter, or a recorder,
which enables many hours of monitoring. See Figure 8. With the 2413R
in the peak hold mode, DC voltage corresponding to 1/ √2 of a peak
current value can be held and output.
Refer to section 5-3, How to Use Peak Hold Function.