Axio MET AX-MS8250 User manual

DIGITALMULTIMETER
USER’S MANUAL
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CONTENTS
1. GENERAL INSTRUCTIONS…………………………… 1
2. DESCRIPTION ………………………………………… . 4
3. TECHNICAL SPECIFICATIONS ………………………. 7
4. OPERATING INSTRUCTION …………………………..13
5. MAINTENANCE ………………………………………….18

1. GENERAL INSTRUCTIONS
This multimeter has been designed according to IEC1010
concerning electronic measuring instruments with an
overvoltage category (CAT II 1000V, CAT III 600V) and
pollution 2.
To get the best service from this instrument, read carefully
this user's manual and respect the detailed safety
precautions.
1.1 Precautions safety measures
1.1.1 Preliminary
* When using this Multimeter, the user must observe all
normal safety rules concerning:
―protection against the dangers of electric current.
―protection of the Multimeter against misuse.
* For your own safety, only use the test probes supplied with
the instrument. Before use, check that they are in good
condition.
1.1.2 During use
* If the meter is used near noise generating equipment, be
aware that display may become unstable or indicate large
errors.
* Do not use the meter or test leads if they look damaged.
* Use the meter only as specified in this manual; otherwise,
the protection provided by the meter may be impaired.
* Use extreme caution when working around bare
conductors or bus bars.
* Do not operate themeter around explosive gas,vapor, or dust.
* Check the main function dial and make sure it is at the
correct position before each measurement.

* When the range of the value to be measured is unknown,
check that the range initially set on the multimeter is the
highest position.
* To avoid damages to the instrument, do not exceed the
maximum limits of the input values.
* Caution when working with voltages above 60Vdc or 30Vac
rms. Such voltages pose a shock hazard.
* When using the probes, keep your fingers behind the finger
guards.
* Before changing functions, disconnect the test leads from
the circuit under test.
* Disconnect circuits power and discharge all high-voltage
capacitors before testing resistance, continuity or diode.
* Before attempting to insert transistors for testing, always be
sure that test leads have been disconnected from any
measurement circuits．
*Components should not be connected to the hFE socket
when making voltage measurements with test leads．
* Before measuring current, turn off power to the circuit
before connecting the meter to the circuit.
* Change the battery when the symbol appears to
avoid incorrect data.
1.1.3 Symbols:
Symbols used in this manual and on the instrument:
Caution:refer to the instruction manual. Incorrect use may
result in damage to the device or its components.
Earth
This instrument has double insulation.
Fuse: F 500mA/250V

1.1.4 Instructions
* Before opening up the instrument, always disconnect from
all sources of electric current and make sure you are not
charged with static electricity, which may destroy internal
components.
*Any adjustment, maintenance or repair work carried out on
the meter while it is live should be carried out only by
appropriately qualified personnel, after having taken into
account the instructions in this present manual.
*If any faults or abnormalities are observed, take the
instrument out of service and ensure that it can not be used
until it has been checked out.
*If the meter is not going to be used for a long time, take out
the battery and do not store the meter in high temperature
or high humidity environment.
*For continue protection against fire, replace fuse only with
the specified voltage and current rating: F500mA/250V.
*Never use the meter unless the back cover and battery
cover are in place and fastened fully.

2. DESCRIPTION
2.1 Instrument Familiarization
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1
2
3
4
5
6
EF-DETECT Area
LCD display
Keypad
Back light key
Rotary switch
Terminals

2.2 LCD Display
3 3/4 digit, 18 mm high LCD.
2.3 ON/OFF key
¥This key is used to turn the meter on or off
2.4 FUNC. key
¥Selection of the dc (default) or ac mode and the
(default) or mode: press on the key, the beep sounds
briefly.
¥This key is operative in Aand ( ) ranges.
2.5 RANGE key
¥Selection of the automatic (default) or manual mode:
short press < 1 sec. on the key, the beep sounds briefly.
¥Switch from manual to autoranging mode:
long press > 1 sec. on the key, the beep sounds briefly.
¥In manual mode, ranges selection:
press successively < 1 sec. on the key.

¥This key is operative in V and Ω ranges.
2.6 HOLD key
¥Fixes the display on the current value and memories it
(short press).
¥Asecond short press returns the meter to normal mode.
2.7 REL key
¥Selection of the Relative measurement mode, press on the
key, the beep sounds briefly.
¥This key is operative in V, A, Ω and CAP ranges.
2.8 Back light key
¥This key is used to turn the back light on or off. Press the
key >2 sec. the backlight will be turned on. Press the key
again , the backlight will be turned off.
¥the key is’t operative in range.
2.9 Rotary switch
This switch is used to select functions and desired ranges .
There are different functions and 11 ranges provided.
2.10 Terminals
¥VΩ
ΩΩ
ΩHz℃
℃℃
℃ ： Terminal receiving the red lead for voltage,
resistance, capacitance, temperature, frequency, diode and
continuity measurements.
¥COM：Terminal receiving the black lead as a common

reference.
¥uAmA ：Terminal receiving the red lead for uAmA
measurement..
¥10A ：Terminal receiving the red lead for 10A
measurement.
3. TECHNICAL SPECIFICATIONS
3.1 General specifications
¥Environment conditions:
600V CAT.III and 1000V CAT.Ⅱ
Pollution degree: 2
Altitude < 2000 m
Operating temperature:
0~40
O
C, (<80% RH, non-condensing)
Storage temperature:
-10~60
O
C, (<70% RH, battery removed)
¥Temperature Coefficient:
0.1×(specified accuracy) /
O
C (<18
O
C or >28
O
C)
¥MAX. Voltage between terminals and earth ground:
750V AC rms or 1000V DC
¥Fuse Protection:
uAmA: F 500mA/250V ∅5×20
¥Sample Rate: 3 times/sec for digital data.
¥Display: 3 3/4 digits LCD display with max. reading 3999,
Automatic indication of functions and symbols.
¥Range selection: automatic and manual.

¥Over Range indication: LCD will display "OL".
¥Low battery indication:
The " " is displayed when the battery is under the proper
operation range.
¥Polarity indication: " − " displayed automatically.
¥Auto power off:
If there is no key or dial operation for 15 minutes, the meter
will power itself off to save battery consumption.
One minute before power off, the beeper will sound 5
sounds. The beeper will sound again before power off.
¥Power source: 4.5V battery
¥Dimensions: 156(L)×82(W)×29(H) mm.
¥Weight: 220g. Approx. (battery included).
¥Accessories:User's manual.Test leads. Carry case.
“K” type thermocouple
3.2 Measurement specifications
*Accuracy: ±(% of reading + number of digits) at 18
O
C to
28
O
C (64
O
F to 82
O
F) with relative humidity to 80%.
3.2.1 No contact AC Voltage detector
Sensitivity Frequency distance
>50V 50Hz < 150mm
3.2.2 DC Voltage
Range Resolution Accuracy
400mV 0.1mV ±(0.8% of rdg +3 digits)

4V 1mV
40V 10mV
400V 100mV
1000V 1V ±(1.0% of rdg +3 digits)
Input impedance: 10MΩ
Maximum input voltage: 1000V dc or 750V ac rms.
3.2.3 AC Voltage
Range Resolution Accuracy
4V 1mV
±（1.0% of rdg +3 digits）40V 10mV
400V 100mV
750V 1V ±（1.2% of rdg +3 digits）
Input impedance: 10MΩ
Maximum input voltage: 1000V dc or 750V ac rms.
Frequency Range: 40Hz-400Hz,
Response:Average, calibrated in rms of sine wave
3.2.4 DC Current
Range Resolution Accuracy
4000uA 1µA ±（1.2% of rdg +3 digits）
400mA 0.1mA
10A 10mA ±（2.0% of rdg +8digits）
Overload protection: F 500mA/250V fuse for uAmA range.

Maximum input current: 400mA dc or 400mA ac rms for µA
and mA ranges.
10A dc or 10A ac rms for 10A
ranges.
3.2.5 AC Current
Range Resolution Accuracy
4000uA 1µA ±（1.5% of rdg + 5 digits）
400mA 0.1mA
10A 10mA ±（3.0% of rdg + 8 digits）
Overload protection: F 500mA/250V fuse for uAmA range.
Maximum input current: 400mA dc or 400mA ac rms for µA
and mA ranges.
10A dc or 10A ac rms for 10A
ranges.
Frequency Range: 40Hz-400Hz,
Response:Average, calibrated in rms of sine wave
3.2.6 Resistance
Range Resolution Accuracy
400Ω0.1Ω
±(1.2% of rdg +3digits)
4kΩ1Ω
40kΩ10Ω
400kΩ100Ω
4MΩ1kΩ
40MΩ10kΩ±(2.0% of rdg +5 digits)

Open circuit voltage: approx. 0.25V
Overload protection: 250V dc or 250V ac rms.
3.2.7 Diode and Audible continuity Test
Range description Test Condition
Built-in buzzer
sounds if
resistance is less
than approx.40Ω
Open circuit voltage:
approximate 0.5V
Display read
approx. forward
voltage of diode
Forward DC Current:
approx. 1mA
Reversed DC Voltage:
approx. 1.5V
Overload protection: 250V dc or 250V ac rms.
3.2.8 Temperature
Range Resolution Accuracy
-20℃to 0℃1℃±(5% of rdg +4 digits)
0℃to 400℃1℃±(1% of rdg +3 digits)
400℃to 1000℃1℃±(2% of rdg +3 digits)
Overload protection: 250V dc or 250V ac rms.
3.2.9 Capacitance
Range Resolution Accuracy
4nF 1pF ±（5.0% of rdg +5 digits）
40nF 10pF ±（3.0% of rdg +5 digits）

400nF 100pF
4µF 1nF
40µF 10nF
200µF 100nF
Overload protection: 250V dc or 250V ac rms.。
3.2.10 Frequency
Range Resolution Accuracy
9.999Hz 0.001 Hz
±（0.1% of rdg +1 digit）
99.99Hz 0.01 Hz
999.9Hz 0.1 Hz
9.999kHz 1Hz
99.99kHz 10Hz
199.9kHz 100Hz
>200kHz 100Hz Unspecified @ >200kHz
Overload protection: 250V dc or 250V ac rms.
Input Voltage range: 0.6V-3V ac rms (Input voltage must be
enlarged with increasing frequency
under measurement)

4. OPERATING INSTRUCTION
4.1 No contact AC Voltage detector
There is no auto power off function. And the
backlight is’t operative in this range.
¥Set rotary switch to the range. Then the green LED
of the LED indicator is bright.
¥Put the EF-DETECT AREA close to the lead or the power
socket , if AC electrical voltage is present , the red LED
indicator which in the top of the meter will flash and the
audible warning will sound,and the figure will be
displayed on the LCD.
4.2 Voltage measurement
To avoid electrical shock and/or damage to the
instrument, do not attempt to take any voltage
measurement that might exceeds 1000Vdc or
750Vac rms. Do not apply more than 1000Vdc or
750Vac rms between the common terminal and
the earth ground.
¥Set rotary switch to the V (ACV or DCV) range.
¥Press "RANGE" key to select manual range
¥Connect the black and red test leads to the COM and V

terminals respectively
¥Connect the test leads to the circuit being measured
¥ Read the displayed value. The polarity of red test lead
connection will be indicated when making a DC
measurement.
4.3 Resistance measurement
To avoid electrical shock and/or damage to the
instrument, disconnect circuit power and
discharge all high-voltage capacitors before
measuring resistance.
¥Set the rotary switch to Ωrange.。
¥Connect the black and red test leads to the COM and VΩ
terminals respectively.
¥Connect the test leads to the circuit being measured and
read the displayed value.
¥In order to ensure the best accuracy in measurement of
low resistance, short the test leads before measurement
and memory the test probe resistance in mind. This
necessary to subtract for the resistance of the test leads.
NOTE:
¥For measuring resistance above 1MΩ, the meter may take
a few seconds to stabilize reading. This is normal for high
resistance measuring.
¥When the input is not connected, i.e. at open circuit, the
figure "OL" will be displayed for the overrange condition.

4.4 Continuity measurement
To avoid electrical shock and/or damage to the
instrument, disconnect circuit power and
discharge all high-voltage capacitors before
testing for Continuity.
。
。。
。
¥Set the rotary switch to ( ) range.
¥Press "FUNC." key to select measuring mode.
¥Connect the black and red test leads to the COM and Ω
terminals respectively.
¥Connect the test leads to the resistance in the circuit being
measured.
¥When the test lead to the circuit is below 40Ω, a continuous
beeping will indicate it.
Note: continuity test is available to check open/short of the
circuit.
4.5 Diode measurement
To avoid electrical shock and/or damage to the
instrument, disconnect circuit power and
discharge all high-voltage capacitors before
testing diodes.
¥Set the rotary switch to ( ) range.
¥Press "FUNC." key to select measuring mode.
¥Connect the black and red test leads to the COM and Ω
terminals respectively.
¥Connect the red test lead to the anode, black test 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 "OL"
displayed.

4.6 Capacitance measurement
To avoid electrical shock and/or damage to the
instrument, disconnect circuit power and
discharge all high-voltage capacitors before
measuring capacitance. Use the dc voltage
function to confirm that the capacitor is
discharged.
¥Set the rotary switch to range.
¥Connect the black and red test leads to the COM and
terminals respectively.
¥Connect the test leads to the capacitor being measured
and read the displayed value.
NOTE:
¥The meter may take a few seconds (200µF range, 30
seconds) to stabilize reading. This is normal for high
capacitance measuring.
¥To improve the accuracy of measurements less than 4nF,
subtract the residual capacitance of the meter and leads.
4.7 Frequency measurement
¥Set the rotary switch to Hz range.
¥Connect the black and red test leads to the COM and Hz
terminals respectively.
¥Connect the test leads across the source or load under
measurement, and read the displayed value.

Note:
¥Reading is possible at input voltages above 3V rms, but
the accuracy is not guaranteed.
¥In noisy environment, it is preferable to use shield cable for
measuring small signal.
4.8 Temperature measurement
To avoid electrical shock, do not connect the
thermocouples with the electriferous circuit.
¥Set the rotary switch to ℃range.And the LCD display will
show the current environment temperature.
¥Connect the red lead of“K” type thermocouple
into the ℃jack and the black lead of“K”type
thermocouple into the “COM” jack.
¥Contacting the object be measured with the
thermocouple probe.
¥Read temperature value on the LCD display.
4.9 Current measurement
To avoid damage to the meter, check the meter's
fuse before proceeding. Use the proper terminals,
function, and range for your measurement.
¥ Set the rotary switch to the 4000µA, 400mA or 10A range.
¥ Press "FUNC." key to select DCAor ACAmeasuring mode.
¥Connect the black test lead to the COM terminal and the
red test leads to the mA terminal for a maximum of 400mA.

For a maximum of 10A, move the red test lead to the 10A
terminal.
¥Connect test leads in series with the load in which the
current is to be measured.
¥Read the displayed value. The polarity of red test lead
connection will be indicated when making a DC
measurement.
¥When only the figure "OL" displayed (Buzzer will sound
continually), it indicates overrange situation and the higher
range has to be selected.
4.10 Misplug Alarm
To avoid damage to the meter,the meter
provide “Misplug Alarm” function. When the
meter alarm , please check the range and the
terminal of the lead.
Following operation will bring alarm:
¥ Set the rotary switch to the any range expect Aand
range , Connect the test lead to the uAmAor 10Aterminal,
meter alarm.
¥ Set the rotary switch to the uA or mA range, Connect the
test lead to the 10Aterminal, meter alarm.
¥ Set the rotary switch to the 10A range, Connect the
test lead to the uAmAterminal, meter alarm.