YOKOGAWA CL155 User manual

User's
Manual
CL155
Clamp-on Tester
クランプテスタ
IM CL155
保証書付
IM CL155
2021.11 11版（ KYOU）

Contents
■Precautions for Safety Use of the Instrument ……………………………… i
1. Instrument Layout …………………………………………………………… 1
2. Measurement ………………………………………………………………… 3
2.1 Preparation for Measurement ……………………………………………… 3
2.2 Current Measurement ……………………………………………………… 3
2.2.1 AC Current Measurement (Normal Mode) ……………………………… 4
2.2.2 Peak Current Measurement (Peak Mode) ……………………………… 4
2.3 Voltage Measurement ……………………………………………………… 5
2.3.1 DC Voltage Measurement ………………………………………………… 5
2.3.2 AC Voltage Measurement ………………………………………………… 5
2.4 Resistance Measurement …………………………………………………… 6
2.4.1 Resistance Measurement (Normal Mode) ……………………………… 6
2.4.2 Continuity Check (400Ωrange fixed) …………………………………… 6
3. Other Functions ……………………………………………………………… 8
3.1 Sleep Function ……………………………………………………………… 8
3.2 Data Hold Function ………………………………………………………… 8
3.3 OUTPUT Terminal (For current measurement only) …………………… 9
3.4 Optional Accessories ……………………………………………………… 10
4. Battery Replacement ……………………………………………………… 11
5. Specifications ……………………………………………………………… 12
6. Calibration and After-sales Service ……………………………………… 15

iIM CL155
■PrecautionsforSafeUseoftheInstrument
When handling the instrument, ALWAYS observe all of the cautionary notes on
safety given below. Yokogawa M&C Corporation is not at all liable for damage
resulting from misuse of this product by the user that is contrary to these
cautionary notes.
Various symbols are used on the instrument and in this manual to ensure the
product is used safety and to protect operators and property from possible
hazards or damage. The following safety symbols are used where appropriate.
Read the explanations carefully and familiarize yourself with the symbols
before reading the text.
The instrument and this manual use the following safety symbols:
Danger! Handle with Care.
This symbol indicates that the operator must refer to an explanation
in the Users Manual in order to avoid the risk of personal injury or
death and/or damage to the instrument.
Double Insulation
This symbol indicates double insulation.
AC Voltage/Current
This symbol indicates AC voltage or current.
DC Voltage/Current
This symbol indicates DC voltage or current.
Ground
This symbol indicates ground (earth)
This symbol 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.
WARNING
Indicates that there is a possibility of serious personal injury or loss of life if the
operating procedure is not followed correctly and describes the precautions for
avoiding such injury or loss of life.
CAUTION
Indicates that there is a possibility of serious personal injury of damage to the
instrument if the operating procedure is not followed correctly and describes
the precautions for avoiding such injury or damage.
NOTE
Draws attention to information essential for understanding the operation and
features.

IM CL155 ii
WARNING
●Never make measurement on a circuit above 750V AC or 1000V DC.
●Do not use the instrument in an atmosphere where any flammable or
explosive gas is present.
●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.
●Avoid using the instrument if it has been exposed to rain or moisture or if
your hands are wet.
●Do not exceed the maximum allowable input of any measurement range.
●Never open the battery compartment cover when making measurement.
●Do not use the instrument if there is any damage to the casing or when the
casing is removed.
●Do not turn the Function Selector switch with plugged in test leads
connected to the circuit under test.
●Do not install substitute parts or make any modification to the instrument.
Return the instrument to Yokogawa M&C or your distributor for repair or
re-calibration.
●Always switch off the instrument before opening the battery compartment
cover for battery replacement.
●Do not use the test leads that have deteriorated or are detective.
●Check the test leads continuity
WARNING
To avoid damage to the instrument or electric shock!
The restrictions on the maximum voltage level for which the CL155 testers can
be used, depend on the measurement categories specified by the safety
standards. These category specifications are formulated to protect operators
against transient impulse voltage in power lines.
Function
Maximum Allowable Input
MEASUREMENT
CATEGORY II
MEASUREMENT
CATEGORY III
MEASUREMENT
CATEGORY Ⅳ
A
AC 2000A rms
Measuring circuit
voltage:
AC 750V rms
AC 2000A rms
Measuring circuit
voltage :
AC 600V rms
AC 2000A rms
Measuring circuit
voltage :
AC 300V rms
V, V AC 750V rms
/DC 1000V AC 600V rms
/DC 600V
AC 300V rms
/DC 300V
Input terminal-to-
ground voltage
AC 750V rms
/DC 1000V

iii IM CL155
O (None, Other)
applies to measurement of circuits that are not directly connected to a main
power supply.
Measurement category II (CAT II)
applies to measurement of circuits that are connected to low-voltage
installations.
Measurement category III (CAT III)
applies to measurement of facility circuits.
Measurement category IV (CAT IV)
applies to measurement of power source circuits for low-voltage
installations.
CAUTION
●Always make sure to insert each plug of the test leads fully into the
appropriate terminal on the instrument.
●Make sure to remove the test leads from the instrument before making
current measurement.
●Be sure to set the Function Selector switch to the "OFF" position after use.
When the instrument will not be in use for a long period of time, Place it in
storage after removing the battery.
●Using this instrument is limited to under residential, commercial and light-
industrial environment.
This instrument may not be able to measure accurately if it is near other
equipment generating strong electromagnetic interference or a strong
magnetic field caused by large current.
●Use a damp cloth and detergent for cleaning the instrument. Do not use
abrasives or solvents.

IM CL155 1
1.InstrumentLayout
(1)Transformer Jaws : Pick up current flowing through the conductor.
(2)Open/Close Lever : Operates the transformer jaws. Press to open the
Transformer Jaws.
(3)Function Selector Switch : Selects ranges. Also used to power the
instrument on.
(4)Data Hold Button : Freezes the display reading. " " is shown on the
display when Data Hold is enabled.
(5) Mode Selector Button : On a AC current (" 400A" or " 2000A" or
the resistance ( ) range. Press the mode button to cycle through the
measurement modes. The instrument is initially set to the normal mode and
can be switched to peak or continuity check mode by means of the mode
button.

2IM CL155
A / V
(ACA/ACV) (Resistance/Continuity)
Display Display
Normal
↓
Peak
Resistance
↓
Continuity
check
Ω
(6) Button : Reset the measurement in peak mode.
(7)LCD Display : Field effect type of liquid crystal display with maximum counts
of 3999. Function symbols and decimal point are controlled by the
microprocessor based on the selected function and measuring mode.
(8)Terminal Cover : Slides over Hi and Lo Terminals to prevent access to them
when OUTPUT terminal is in use.
(9)OUTPUT Terminal (For " 400A" or " 2000A" range only) : Provides DC
voltage output in proportion to the AC or DC current reading. (See section
3.3, OUTPUT Terminal.) The output is connected to a recording device such
as a chart recorder for long hour monitoring. No output is available on
voltage and resistance ranges.
(10) Lo Terminal : Accepts the black test lead for voltage or resistance
measurement.
(11) Hi Terminal : Accepts the red test lead for voltage or resistance
measurement.
(12) Safety Hand Strap : Prevents the instrument from slipping off the hand
during use.
(13) Test Leads (Model 98072) : Connected to Lo and Hi terminals for voltage
or resistance measurement.
(14) Barrier: It is a part providing protection against electrical shock and
ensuring the minimum required air and creepage distances.

IM CL155 3
2.Measurement
2.1PreparationforMeasurement
CAUTION
●The jaw section is a delicate, precision sensor. Do not subject the jaw to
unreasonably strong shock, vibration, or force when using it.
●If dust gets into the tops of the jaws, remove it immediately. Do not close the
jaws when dust is trapped in its joints as the sensor may break.
●Please check that the function and mode are set to the desired setting
before measurement.
2.2CurrentMeasurement
WARNING
●Do not make measurement on a circuit above 750VDC. This may cause
shock hazard or damage to the instrument or equipment under test.
●Do not make current measurement with the test leads connected to the Hi
and Lo terminals.
●When measuring current is not less than 1000A, make sure to stop
measurement within the maximum measuring time shown below. Otherwise,
transformer jaws may heat to cause a fire or deformation of molded parts,
which will degrade insulation.
1000 to 1500A : 15min. 1500 to 2000A : 5min.
●Keep your fingers and hands behind the barrier during measurement.

4IM CL155
2.2.1ACCurrentMeasurement(NormalMode)
(1)Set the Function Selector switch to the " 400A" or " 2000A" position.
"AC" should be shown on the upper left corner of the display.
(2)Press the open/close lever to open the transformer jaws and clamp them
onto the conductor under test, then take the reading on the display. The
most accurate reading will be obtained by keeping the conductor at the
center of the transformer jaws.
NOTE
●During current measurement, keep the transformer jaws fully closed.
Otherwise, accurate measurement cannot be made. The maximum
measurable conductor size is approx. 54.5mm in diameter.
●The transformer jaws may buzz when measuring large current. This has no
effect on the instruments performance or safety.
2.2.2PeakCurrentMeasurement(PeakMode)
(1) Set the Function Selector switch to the " 400A" or " 2000A" position.
(2) Press the button once to enter from the normal mode to the PEAK
mode. " " should be shown on the display.
(3) Press the open/close lever to open the transformer jaws and clamp them
onto the conductor under test. Then, press the button.
(4) The display shows the currents crest value divided by the square root of
two. Therefore, when the current is sinusoidal, the reading equals RMS
value.
(5) To reset the display, press the button.
(6) After the measurement is over, press the button to return to the
normal mode.
NOTE
●In the Peak measurement mode, the data hold feature is disabled.
●In the Peak measurement mode, the response time is 10ms.

IM CL155 5
2.3VoltageMeasurement
WARNING
Do not make measurement on a circuit above 750V AC or 1000V DC. This
may cause shock hazard or damage to the instrument or equipment under
test.
2.3.1DCVoltageMeasurement
(1) Set the Function Selector switch to the " V " position. "DC" should be shown
on the upper left corner of the display.
(2) Slide the terminal cover to the left to disclose the Hi and Lo terminals. Plug
the red test lead into the Hi terminal and the black test lead into Lo terminal.
(3) Connect the tip of the red and black test leads to the positive (+) and
negative (-) sides of the circuit under test respectively. Take the reading on
the display.
2.3.2ACVoltageMeasurement
(1) Set the Function Selector switch to the " V " position. "AC" should be shown
on the upper left corner of the display.
(2) Slide the terminal cover to the left to disclose the Hi and Lo terminals. Plug
the red test lead into the Hi terminal and the black test lead into Lo terminal.
(3) Connect the tip of the test leads to the circuit under test respectively. Take
the reading on the display.
NOTE
For high sensitivity, there are parts which do not indicate "0".