User’s
Range Resolution
30 mA 0.01 mA
300 mA 0.1 mA
30 A 0.01 A
300 A 0.1 A
Accuracy (50/60 Hz)
1% + 5
0 to 200 A: 1.2% + 5
200 to 300 A: 5% + 5
Maximum Allowable Current
300 Arms
Range
3 mA
30 mA
30 A
60 A
0.001 mA 1% + 5
60 Arms
0 to 50 A: 1% + 5
50 to 60 A: 5% + 5
0.01 mA
0.01 A
0.1 A
Resolution Accuracy (50/60 Hz) Maximum Allowable Current
Manual
Models 300 30/31
Leakage Clamp-on Tester
Store this manual in a safe
place for future reference.
IM 30030E
1st Edition: Feb . 1999
3rd Edition: Mar . 2001
Copyright Feb. 1999(YG). 3rd Edition; Mar. 2001(YG)
YOKOGAWA M&C CORPORATION
International Sales Dept.
2-9-32 Nakacho, Musashino-shi, Tokyo, 180-8750 Japan
Phone: 81-422-52-5716 Facsimile: 81-422-55-8954
YOKOGAWA CORPORATION OF AMERICA (U.S.A.)
Phone: 1-770-253-7000 Facsimile: 1-770-251-2088
YOKOGAWA EUROPE B. V. (THE NETHERLANDS)
Phone: 31-334-64-1611 Facsimile: 31-334-64-1610
YOKOGAWA AMERICA DO SUL S. A. (BRAZIL)
Phone: 55-11-5681-2400 Facsimile: 55-11-5681-1274
YOKOGAWA ENGINEERING ASIA PTE. LTD. (SINGAPORE)
Phone: 65-6241-9933 Facsimile: 65-6241-2606
YOKOGAWA MEASURING INSTRUMENTS KOREA CORPORATION (KOREA)
Phone: 82-2-551-0660 to -0664 Facsimile: 82-2-551-0665
YOKOGAWA AUSTRALIA PTY. LTD. (AUSTRALIA)
Phone: 61-2-9805-0699 Facsimile: 61-2-9888-1844
YOKOGAWA BLUE STAR LTD. (INDIA)
Phone: 91-80-227-1513 Facsimile: 91-80-227-4270
LTD. YOKOGAWA ELECTRIC (RUSSIAN FEDERATION)
Phone: 7-095-737-7868 Facsimile: 7-095-737-7869
Safety precautions
Various symbols are used on the instrument and throughout this manual
to ensure safe use of the product and to protect against 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.
WARNING
CAUTION
The following safety symbols are used on the instrument and in this
manual:
Caution
This symbol indicates that the operator must refer to an explanation in the instruction manual in order to avoid the risk of
injury or death of personnel or damage to the instrument.
Double Insulation
This symbol indicates double insulation.
Alternating Current
This symbol indicates AC voltage/current.
Direct Current
This symbol indicates DC voltage/current.
Earth TERMINAL
This symbol indicates ground.
WARNING
■ To avoid electric shock!
• Do not use the instrument if there is any damage to the casing
or when the casing is removed.
• Disconnect the instrument from the measurable conductors under test before opening the casing to replace the battery.
•Avoid using the instrument if it has been exposed to rain or
moisture or if your hands are wet.
■ To avoid electric shock or fire!
Do not use the instrument in an atmosphere where any flammable or explosive gas is present.
WARNING
■ To avoid damage to the instrument or electric shock!
The restrictions on the maximum voltage level for which the
300 30 and 300 31 testers can be used, depend on the overvoltage categories specified by the safety standards. These category specifications are formulated to protect operators against
transient impulse voltages in power lines.
Model Maximum Allowable Input
Over-voltage
category (CAT.)
300 30 III 300 Arms
300 31 III 60 Arms
Over-voltage category I (CAT.I):
Signal level, special equipment or parts of equipment, telecommunication, electronic etc., with smaller transient over-voltages than
CAT.II.
Over-voltage category II (CAT.II):
Local level, appliances, portable equipment etc., with smaller transient over-voltages than CAT .III.
Over-voltage category III (CAT.III):
Distribution level, fixed installation, with smaller transient overvoltages than CAT.IV.
CAUTION
• Do not use the instrument near noise-emitting equipment or
where there may be sudden changes in temperature. Otherwise,
the instrument may produce an unstable readings or errors.
• Do not wipe the instrument using an organic solvent such as
benzine or paint thinner. Otherwise, the front panel may be
damaged or discolored. When cleaning the instrument, use a
dry cloth.
• Do not leave the tester exposed to direct sunlight or in a hot and
humid location such as the inside of a car, for any prolonged
length of time.
NOTE
• Radiation immunity affects the accuracy of 300 30 and 300 31
testers under the conditions specified in EN 61326-1.
•
If equipment generating strong electromagnetic interference is
located nearly, the testers may malfunction.
This symbol indicates that misuse of the instrument could result in injury or death of personnel.
This symbol indicates that misuse of the instrument could result in injury of personnel or damage to the instrument.
(Voltage of circuit under test: 300 Vrms AC)
(Voltage of circuit under test: 300 Vrms AC)
Components
1) Jaw Section
Is a precision sensor for detecting currents.
2) Open/Close Lever
Opens and closes the jaws.
3) Display
Shows the measured value (digital reading or bar graph), unit, function and low-battery symbol ( ).
4) mA/A Selector Switch
Selects the unit of AC current (either “mA” or “A”) to be measured.
5) Data Hold Switch
Retains the measured data. If you press this switch, the
appears and the data is retained. If you press this switch once again,
data holding is canceled (the
D • H
symbol disappears).
D • H
symbol
6) Power Switch
Turns on the power to the instrument.
7) Battery Housing
Contains the battery.
Jaw
‚s
50/60Hz
section
`
‚`
‚O
‚O
‚R
D
mA/A
30
selector
switch
Display
‚c‚`‚s‚`
‚g‚n‚k‚c
AUTO POWER OFF
POWER
Data hold
switch
Power
switch
Battery
housing
CR2032 X1
BATTERY
3V
A `:30/300mA
RANGE
30/300A
No.
Yokogawa M&C Corporation
Made in Japan
Hand stra
Open/
close lever
‚R
‚O
‚
O
‚u
`
‚b
‚`
‚k‚d‚`‚j
300
CLAMP-ON TESTER
`‚ ‚`
`‚`
Measuring Instructions
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.
AC Current Measurement (unit: mA/A)
a) Press the POWER switch to turn on the power.
b) Squeeze the open/close lever to open the jaws. Insert a wire from the
measurable conductors under test through the jaws, making sure the
tops of the jaws are tightly shut.
c) When the reading stabilizes, read the value. If you have difficulties
in reading the value, use the DATA HOLD function.
d) When you have finished measurement, press the POWER switch to
turn off the tester.
• Examples of Leakage Current Measurement
(1) (3)
‚R
‚O
‚O
‚u
`
‚b
‚k‚d‚`‚j
300
CLAMP-ON TESTER
‚`
‚s
D
30
50/60Hz
Load
`
‚`
‚O
‚O
‚R
`
‚`
‚O
‚O
‚R
`
‚u
‚O
‚O
‚R
D
‚s
‚`
‚b
‚k‚d‚`‚j
30
50/60Hz
300
CLAMP-ON TESTER
Load
`‚`
`‚ ‚`
‚R
`
‚O
‚`
‚O
‚u
‚O
‚O
`
‚R
‚b
‚`
‚s
D
‚k‚d‚`‚j
30
300
CLAMP-ON TESTER
50/60Hz
Single-phase
Two-wire Circuit
(2)
‚R
`
‚O
‚`
‚O
‚u
‚O
‚O
`
‚R
‚b
‚`
‚s
D
‚k‚d‚`‚j
30
300
CLAMP-ON TESTER
50/60Hz
Single-phase Threewire or Three-phase
Three-wire Circuit
Insert only one of the wires through the jaws.
Load
Grounding Wire
• Example of Load Current
Load
Measurement
AUTO POWER OFF Function
The tester automatically turns off 10 minutes after the last switch operation. A buzzer starts to beep 15 seconds before the automatic power-off.
Battery Replacement
If the battery voltage drops below the operating voltage, the symbol turns on. If this happens, replace the battery with a new one (CR2032
lithium battery) as soon as possible.
CAUTION
• There is a risk of electrical shock during battery replacement.
always remove the tester from the measurable conductors under test before replacing the battery.
• Use a battery of the same model.
To replace the battery:
a) Press the POWER switch to turn off the power.
b) T urn the battery cover on the backside of the tester in the direction of
the arrow using a coin or a Phillips screwdriver.
c) Remove the cover and the battery.
d) Insert a new battery, making sure that the polarities are correct.
e) Close the cover back in place by turning it in the reverse direction of
the arrow.
Inserting a Battery Closing the Battery Cover
Insert the battery being careful
that the polarities are correct.
Close the battery cover, aligning
the arrow's tail with the dot and
then turn clockwise.
Battery cover
Specifications
■ General Specifications
• Measurement functions: AC current
• Additional functions: Data hold and Auto power-of f
• Display (LCD): Digital reading ........ 3200 counts
• Range selection: Automatic (Which range is within mA or A)
•Sampling: Digital reading ........ 2 times/sec
• Operating temperature and humidity range:
• Storage temperature and humidity range:
•Temperature coef ficient:
•Effect of external magnetic fields:
• Diameter of measurable conductors: 40 mm (Maximum)
• Circuit voltage limit: 300 Vrms or less
•Withstanding voltage: 3.7 kV AC for one minute
• Power consumption: 5mW maximum for Model 300 30
• Automatic power-off: Automatically turns of the power approx. 10
• Power supply: CR2032 lithium battery................................ 1
• Battery life: Approx. 120 hours (of continuous operation)
• Dimensions: 70 (W) ⫻ 176 (H) ⫻ 25 (D) (mm), excluding
•Weight: Approx. 180 g for Model 300 30 (including the
Bar graph ................ 32 segments
“OL” over-range indication
low-battery symbol
Bar graph ................ 12 times/sec
0 to 50°C, with a maximum humidity of 80%
RH (no condensation)
-20 to 60°C, with humidity range is 20 to 70%
RH (no condensation)
Model 300 30: ±0.05% of measuring range/°C
when the measuring range is 0 to 200 A over a
temperature range of either 0 to 18°C or 28 to
50°C
Model 300 31: ±0.05% of measuring range/°C
when the measuring range is 0 to 50 A over a
temperature range of either 0 to 18°C or 28 to
50°C
0.01% maximum for Model 300 30 (in terms
of the magnitude of current in adjacent wires)
0.0005% typical value for Model 300 31 (in
terms of the magnitude of current in adjacent
wires)
(Tested between the cores of the jaw section
and the case)
6mW maximum for Model 300 31
minutes after the last switch operation. (The
alarm buzzer begins beeping 15 seconds before
power-off.)
for Model 300 30
Approx. 90 hours (of continuous operation) for
Model 300 31
protrusions
battery)
Approx. 200 g for Model 300 31 (including the
battery)
• Safty standards: EN 61010-1; 1993 +A2; 1995
EN 61010-2-03: 1995
(AC/DC 300 V CAT.III, Pollution degree2,
indoor use)
• EMC standards: EN 55011; 1998 Group 1 Class B
•
Effect of radiation immunity:
EN61326-1;1997+A1; 1998
Accuracy range of reading (Rated accuracy
+4.0% of each range) for the strength of a radio-frequency electromagnetic field of 3v/m.
•
Operable altitude: 2000m or less above sea level.
• Accessories: Battery (housed in the instrument) ...............1
RB057 soft carrying case ............................. 1
Instruction manual........................................ 1
■ Electrical Specification
Test condition: 23 ±5°C and 80% RH maximum
Accuracy: ±(percent of reading + LSD reading)
•AC current measurement
Model 300 30 Mean-value detection and rms-value calibration
Model 300 31 Mean-value detection and rms-value calibration
Zero correction: Fractions smaller than approximately 0.01 mA
are calibrated to zero.