V&A M266 Series User manual

HANDHELD DIGITAL CLAMP MULTIMETER
M266 Series
Users Manual

Table of Content
1. SAFETY INFORMATION................................................................................................ 3
1.1 PRELIMINARY ......................................................................................................... 3
1.2 DURING USE........................................................................................................... 3
1.3 SYMBOLS ................................................................................................................ 4
1.4 MAINTENANCE ....................................................................................................... 4
2 DESCRIPTION ............................................................................................................... 5
2.1 FUNCTIONS AND RANGE SELECTOR.................................................................. 6
2.2 TRANSFORMER JAWS........................................................................................... 6
2.3 DATA HOLD............................................................................................................. 6
2.4 INPUT JACKS .......................................................................................................... 6
3 OPERATING INSTRUCTION ......................................................................................... 7
3.1 MEASURING CURRENT ......................................................................................... 7
3.2 INSULATION TEST.................................................................................................. 7
3.3 MEASURING VOLTAGE.......................................................................................... 8
3.4 MEASURING RESISTANCE.................................................................................... 8
3.5 TESTING DIODE ..................................................................................................... 8
3.6 CONTINUITY TEST ................................................................................................. 8
3.7 MEASURING TEMPERATURE................................................................................ 8
3.8 MEASURING FREQUENCY .................................................................................... 9
4 SPECIFICATIONS .......................................................................................................... 9
4.1 GENERAL ................................................................................................................ 9
4.2 AC CURRENT ........................................................................................................ 10
4.3 INSULATION TEST................................................................................................ 10
4.4 AC VOLTAGE...................................................................................................... 10
4.5 DC VOLTAGE...................................................................................................... 11
4.6 RESISTANCE ........................................................................................................ 11
4.7 TEMPERATURE .................................................................................................... 11
4.8 FREQUENCY ......................................................................................................... 11
5 ACCESSORIES ............................................................................................................ 12
5.1 SUPPLIED WITH THE MULTIMETER................................................................... 12
5.2 OPTIONAL ACCESSORY...................................................................................... 12
6 BATTERY REPLACEMENT ......................................................................................... 12

1. SAFETY INFORMATION
The meter is completely portable, LCD, 3 1/2 digit clamp meter with insulation test
function (with option 500V insulation tester unit). It has been designed according to
IEC61010 concerning electronic measuring instruments with an over-voltage category
(CATIII) and pollution 2 and safety requirements for hand-held current clamps for electrical
measurement and test.
Follow all safety and operating instructions to ensure that the meter is used safely and is
kept in good operating condition.
1.1 PRELIMINARY
* When using this meter, the user must observe all normal safety rules concerning:
- Protection against the dangers of electronic current.
- Protection of the meter against misuse.
* Full compliance with safety standards can be guaranteed only if used with test leads
supplied. If necessary, they must be replaced with the same model or same electronic
ratings. Measuring leads must be in good condition.
1.2 DURING USE
* Never exceed the protection limit values indicated in specifications for each range of
measurement.
* When the meter is linked to measurement circuit, do not touch unused terminals.
* When the value scale to be measured is unknown beforehand, set the range selector at
the highest position.
* Before rotating the range selector to change function, disconnect test leads from the
circuit under test.
* When carrying out measurements on TV or switching power circuits, always remember
that there may be high amplitude voltage pulses at test points which can damage the
meter.
* Never perform resistance measurements on live circuits.
* Always be careful when working with voltage above 60V dc or 30V ac rms. Keep fingers
behind the probe barriers while measuring.
* When the jaw opening and to the conductor under test, your fingers must keep behind
the barrier indicator .The barrier or tactile indicator shall warn the operator of the limit of
safe access.
* Never ground yourself when talking electrical measurement, do not touch exposed
metal pipes, outlets, fixtures, etc., which might be at ground potential. Keep your body
isolated from ground by using dry clothing, rubber shoes, or any approved insulating

material.
* components should not be connect the temperature measuring socket when making
voltage measurement with test leads.
1.3 SYMBOLS
Important safety information, refer to the operating manual.
Dangerous voltage may be present.
Earth ground.
Double insulation ( Protection class II ).
1.4 MAINTENANCE
* Before opening the meter, always disconnect test leads from all sources of electric
current.
* If any faults or abnormalities are observed, the meter can not be used any more and it
has to be checked out.
* Never use the meter unless the back cover and the battery cover are in place and
fastened fully.
* Do not use abrasives or solvents on the meter, use a damp cloth and mild detergent
only.

2 DESCRIPTION
This meter is one of a series handheld 3½digital clamp meter for measuring DC and AC
Voltage, AC current, resistance, continuity test and insulation test. some models also
provide frequency or temperature test. Full overload protection. low battery indication and
over-range indication are provide. Following table shows function of the series of multimeter.
FUNCTION
266
266F
266C
266A
ACV
DCV
※※※※
ACA
※ ※ ※ ※
Ω ※ ※ ※ ※
※ ※
※ ※ ※
INSULATI
ON
※※※
TEMP
※
FREQ
※
PEAK
HOLD
※

1. TRANSFORMER JAWS
2. TRIGGER
3. DATA HOLD SWITCH
4. ROTARY SWITCH
5. LCD DISPLAY
6. INPUT JACKS
7. DROP - PROOF WRIST STRAP
8.TEMPERATURE MEASURING SOCKET
9. BARRIER OR TACTILE INDICATOR
2.1 FUNCTIONS AND RANGE SELECTOR
A rotary switch is used to measurement Functions and Ranges. When the switch is
set to OFF position, the meter does not operate.
2.2 TRANSFORMER JAWS
Pick up the AC current flowing through the conductor. Press the TRIGGER to open
the transformer jaws. When the finger press on the TRIGGER is released, the jaws
will close again.
2.3 DATA HOLD
A push switch (Push ON, Push OFF. All ACA, ACV, DCV, HZ ranges with this
feature)
2.4 INPUT JACKS
This meter has three input jacks that are protected against overload to the limits
shown.
During use connect the black test lead to COM jack and connect red test lead to V
Ωjack. The red test lead is depended on function selected.
The EXT jack is used for accept insulation tester unit EXT banana plugs,when
measurement insulation resistance.

3 OPERATING INSTRUCTION
3.1 MEASURING CURRENT
1. Set the rotary switch at desired A～range position. Press the trigger to open the
transformer jaws and clamp onto one conductor only( Fig1 ), The transformer jaws
pick up the AC current flowing through the conductor.
2. When only the figure “1 ”displayed, it indicates overrange situation and the
higher range has to be selected.
WRONG CORRECT
Fig1
3.2 INSULATION TEST
( Option 500V insulation tester unit )
1. Connect the insulation tester unit VΩ、COM、EXT three banana plugs to the
clamp meter VΩ、COM、EXT.
2. Set the rotary switch of clamp meter at 2000MΩposition.
3. Set the insulation tester unit range switch to the 2000MΩposition.
4. Use the insulation tester unit of the test leads connect its L、E input connect to
being tested installation's. (Test installation's must be power OFF.)
5. Set the insulation tester power switch to the ON position.
6. Depress the PUSH 500V push-push switch, the 500V on red LED lamp will light.
Clamp meter display reading is the insulation resistance value. If the reading is below
19MΩ, change clamp meter and insulation tester unit to 20MΩrange, can be
increase the accuracy.
7. If the insulation tester unit is not use, the power switch must shift to power OFF
position, and the test leads must leave the E.L input connect. That can be increase
battery life and prevent electrical shock hazard.

3.3 MEASURING VOLTAGE
1. Connect the black test lead to the COM jack and the red test lead to the VΩjack.
2. Set the rotary switch at the desired V or V ~range position and connect test
leads across the source or load under measurement.
The polarity of the red lead connection will be indicated along with the voltage
value when making DC voltage measurement.
3. When only the figure “1 ”is displayed,it indicates overrange situation and the
higher range has to be selected.
3.4 MEASURING RESISTANCE
1. Connect the black test lead to the COM jack and the red test lead to the VΩjack.
2. Set the rotary switch at desired Ωposition and connect test leads across the
resistor under measurement.
NOTE:
1. If the resistance being measured exceeds the maximum value of the range
selected or the input is not connected, an overrange indication “1 ”will be
displayed.
2. When checking in - circuit resistance, be sure the circuit under test has all power
removed and that all capacitors have been discharged fully.
3.5 TESTING DIODE
1. Connect the black test lead to the COM jack and the red test lead to the VΩjack.
( The polarity of red lead is “+ ”)
2. Set the rotary switch at position and connect red lead to the anode,black lead
to the cathode of the diode under testing. The meter will show the approx. forward
voltage of the diode. If the lead connection is reversed, only figure “1 ”
displayed.
3.6 CONTINUITY TEST
1. Connect the black test lead to the COM jack and the red test lead to the VΩjack.
( The polarity of the red lead is positive“+ ”)
2. Set the rotary switch at position and connect test leads across two points of the
circuit under testing. If continuity exists ( i.e., resistance less than about 50Ω),
built -in buzzer will sound.
3.7 MEASURING TEMPERATURE
1. Set the rotary switch at °C or °F position and the LCD display will show the
current environment temperature.

2. Insert “K ”type thermocouple into the temperature measuring socket on the
front panel and contact the object to be measured with the thermocouple probe.
Read LCD display.
WARNING: To avoid electric shock, be sure the thermocouple has been
removed before changing to another function measurement.
3.8 MEASURING FREQUENCY
1. Connect the black test lead to the COM jack and the red test lead to the VΩjack.
2. Set the rotary switch at Hz position and connect test leads across the source or
load under measurement.
NOTE:
1. Reading is possible at input voltage above 10Vrms, but the accuracy is not
guaranteed.
2. In noisy environment, it is preferable to use shield cable for measuring small signal.
4 SPECIFICATIONS
Accuracy is specified for a period of one year after calibration and at 18℃to 28℃
( 64 °F to 82 °F ) with relative humidity to 80％.
4.1 GENERAL
Display
: 3½digit LCD, with automatic polarity indication
Measuring Method : Dual-slope integration A-D converter system.
Overrange Indication
: ”1” Figure only in the display.
Max. Voltage Between
Terminals And Earth
Ground
: CAT II 600V
Operating Temperature
: 5
℃
to 35
℃
(21
°
F to 95
°
F)
Storage Environment
: -10
℃
to 50
℃
(14
°
F to 122
°
F)
Power
: 9V alkaline or carbon-zinc battery (NEDA 1604).
Accessories
: Operating manual, set of test leads

Low Battery Indication
: ‘BAT’ to left of display
Optional Accessories
: Thermocouple (K type)
Dimension
Weight
: 90(W)×230(D)×43(H) mm
: 320g (including battery)
4.2 AC CURRENT
Range
Resolution
Accuracy
Note
20A
10mA
±
5.0
％
of rdg
±
5 digits
200A
100mA
±
2.5
％
of rdg
±
5 digits
600A
1A
±
2.5
％
of rdg
±
5 digits
≤600A
＞600A
1000A
1A
±
3.0
％
of rdg
±
5 digits
Frequency Range: 50Hz to 60Hz
Response: Average, Calibrated in rms of sine wave
Overload protection: 1200A within 60 seconds. Jaw Opening: 2" (5cm)
4.3 INSULATION TEST
(With option 500V insulation tester unit )
Range
Resolution
Accuracy
Note
20M
Ω
10K
Ω ±
2.0
％
of rdg
±
2 digits
2000M
Ω
1M
Ω ±
4.0
％
of rdg
±
2 digits
≤
500M
Ω
±
5.0
％
of rdg
±
2 digits
＞
500M
Ω
4.4 AC VOLTAGE
Range
Resolution
Accuracy
200V
0.1V
±
1.0
％
of rdg
±
4 digits
600V
1V
±
1.0
％
of rdg
±
4 digits
Input Impedance: ≥9MΩon all ranges
Overload protection:600V AC/DC on all ranges.
Frequency Range: 50Hz to 500Hz
Response: Average, calibrated in rms of sine wave

4.5 DC VOLTAGE
Range
Resolution
Accuracy
200mV
0.1mV
±
0.5
％
of rdg
±
1 digit
2V
1mV
±
0.5
％
of rdg
±
1 digit
20V
10mV
±
0.5
％
of rdg
±
1 digit
200V
0.1V
±
0.5
％
of rdg
±
1 digit
600V
1V
±
0.8
％
of rdg
±
2 digits
Input Impedance: ≥9MΩ
Over protection: 600V AC/DC on all ranges.
4.6 RESISTANCE
Range
Resolution
Accuracy
200
Ω
0.1
Ω ±
1.0
％
of rdg
±
3 digits
2K
Ω
1
Ω ±
1.0
％
of rdg
±
1 digit
20K
Ω
10
Ω ±
1.0
％
of rdg
±
1 digit
200K
Ω
100
Ω ±
1.0
％
of rdg
±
1 digit
2M
Ω
1K
Ω ±
1.0
％
of rdg
±
1 digit
Over protection: 600V AC/DC on all ranges.
Open circuit voltage: 700mV
4.7 TEMPERATURE
Accuracy
RANGE RESOLUTION 0℃to 400℃
(32
o
F to 752
o
F)
400℃to 750℃
(752
o
F to 1382
o
F)
0℃to 750℃1℃
±
1.0% of rdg
±
3 digits
±
2.0% to rdg
±
1 digit
32
o
F to 1382
o
F
1
o
F
4.8 FREQUENCY
Range
Resolution
Accuracy
2KHz
1Hz
±
1.5
％
of rdg
±
5 digits

5 ACCESSORIES
5.1 SUPPLIED WITH THE MULTIMETER
Test Leads
Battery
Operating Manual
5.2 OPTIONAL ACCESSORY
“K”type thermocouple
INSULATION TESTER UNIT 261
6 BATTERY REPLACEMENT
If the sign“BAT ”appears on the LCD display, it indicates that battery should
be replaced. Remove the battery cover of case. Replace the exhausted battery with a
new one.
WARNING
Before attempting to open the battery cover, be sure that test leads have been
disconnected from measurement circuits to avoid electric shock hazard.
M266-09