Morris 57070 Instruction Manual

Model 57070

DIGITAL
MULTIMETER

INSTRUCTION MANUAL

SAFETY INFORMATION

To ensure safe operation, and in order to exploit to the full
the functionality of the meter, please follow the dire ctions in
this section carefully.

WARNING

This multimeter has been designed according to IEC-1010 concerning
electronic measuring instruments with an overvoltage category CAT II
1000V, CAT III 600V and pollution 2.
Follow all safety and operating instructions to ensure that the meter is
used safely and is kept in good operating condition.
With proper use and care, the digital meter will give you years of
satisfactory service.

● PRELIMINARY

- Wh en using the m eter, the user must observe all n ormal safety
rules concerning:

Protection against the dangers of electrical current.
Protection of the meter against misuse.

- Wh en the mete r is deliv ered, check tha t it has not been dam aged in
transit.

- Test leads must be in good condition. Before using verify that the
insulation on test leads are not damaged and/or the lead wires are
not exposed.

- Full compliance with safety standards can be guaranteed only if used
with test leads supplied. If necessary, they must be replaced with the
same mod el or same elec tric rati ngs.

● DURING USE

- Before using, you must select the right input jack, function and range .

- Nev er exceed t he protect ion limit v alues ind icated in s pecifications
for each range of measurement.

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- When the value scale to be measured is unknown beforehand, set
the range selector at the highest position.

- Do not measure voltage if the voltage on the terminals exceeds
1000V above earth ground.

- Always be careful when working wi th voltages above 60V DC or 30V
AC rms, keep fingers behind the probe barriers while measuring.

- Befo re rotat ing the t rans form s witch to c hange fu ncti ons and r anges,
disconnect test leads from the circuit under test.

- Never perform resistance, transistor and d iod e me as u rem ent s on liv e
circuits.

- Never use the meter under the condition of the expl osive air, steam
or dirt.

- If any faults or abnormalities are observed, the meter cannot be used
any more and it has to be checked out.

- Never us e the meter unless t he rear case is in plac e and fastened
fully.

- Please do not store or use meter in areas exposed to direct sunlight,
high temperature, humidity or condensation.

● SYMBOLS

Important safety information, refer to the operating manual.

Double insulation（Protection class

ΙΙ）.

CAT ΙΙ Overvoltage (Installation) category II, Pollution Degree 2 per

IEC1010-1 refers to the level of Impulse Withstand Voltage
protection provided.

CAT ΙΙΙ Overvoltage (Installation) category III, Pollution Degree 2 per

IEC1010-1 refers to the level of Impulse Withstand Voltage
protection provided.

High voltage warning symbol
Conforms to european union directive
Earth ground

Fuse

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～ Alternating current

Direct current

Diode

H This indicates that the display data is being held.

The b attery is not sufficie nt for proper operatio n.

● MAINTENANCE

-Please d o not attempt to adj ust or repair th e meter by rem oving the
rear case while voltage is being applied. A technician who fully
understands the danger inv olved shou ld only carry out such ac tions.

- Before opening the battery cover or case of the meter, always
disconnect test leads from all tested circuits.

- To avoid the misreadings, when th e meter displays“

”, you must

change the battery.

- For continued protection against fire, replace fuse only with the
specified voltage and current ratings: F 200mA/250V (quick acting).

- Do not use a b ras iv es or so lv en ts on the meter; use a damp cloth and
mild detergent only.

- Always set the power switch to the OFF position when the meter is
not in use.

- If the meter is to be stored for a long period of time, the batteries
should be removed to p revent dam age to the unit.

DESCRIPTION

- This meter is a portable professional measuring instrument with a
handsome LCD for easy reading.

- Single operation of the transform switch makes measurement
convenient. Overload protection and low battery indication are
provided. This meter is id eal for us e in the fiel ds, works hop, scho ol,
hobby and home applications.

- This meter includes the data hold function.

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● NAMES OF COMPONENTS

⑴ LCD Display
⑵ Panel
⑶ H Butt on: This Butt on is used

to the switch of data hold.

⑷ Transform Switch:

This switch is used to select
functions and desired ranges.

⑸ 10A Jack: Input terminal for

current 0 ~ 10A.

⑹ COM Jack: Common terminal

for measurement.

⑺ hFE Jack: This Jack is used

for transistor test.

⑻ V/Ω/mA Jack: Input Jack

SPECIFICATIONS

Accuracy is specified for a pe riod
of 1 year after calibration and at
18℃ to 28℃（64

°F to 82°F）

with relative hum idity to 75%.

● GENERAL SPECIFICATIONS

- Max. Voltage Between Terminals And Earth Ground: 1000V DC or
750V AC

- Fuse Protection: F 2 00mA/250V (quick acting).

- Display: 15mm LCD

- Max. Show Value: 1999 (3-1/2)

- Polarity Indication: ‘-’indicates negative polarity.

- Overrange Indication: Display ‘1’

- Sampling Time: approx. 0.4 second

- Low Battery Indication: ‘

’ displayed

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- Power Supply: 1.5V×3 AAA battery .

- Operating T emperature: 0℃ t o 40℃（32

°F to 104°F）

- Storage Temperature: -10℃ to 5 0℃（10

°F to 122°F）

- Dimension & Weight: 158×74×32 mm, 250g（including battery）

● ELECTRICAL SPECIFICATIONS

Circumstance Temperature: 23℃ ±5℃, Relative Humidity: < 75%

DC Voltage

Range Resolution Accuracy

200mV 0.1mV ±（0.5% of rdg + 2 digits）

2V

0.001V

±（0.5% of rdg + 3 digits）

20V 0.01V ±（0.8% of rdg + 3 digits）

200V 0.1V

1000V 1V ±（0.8% of rdg + 5 digits）

- Input Impedance: 1MΩ

- Overload Protection: 200mV range: 250V DC or AC rms, 2V-1000V
ranges: 1000V DC or 750VAC rms.

- Max. Input Voltage: 1000V DC

AC Voltage

Range Resolution Accuracy

200V 0.1V ±（1.2% of rdg + 10 digits）
750V 1V

- Input Impedance: 1MΩ

- Overload Protection: 750V AC rms or 1000V DC

- Frequency Range: 40 to 400Hz

- Response: Average, calibrated in rms of sine wave.

- Max. Input Voltage: 750V rms AC

Diode

Range Resolution Function

0.001V Display: read approximate forward
voltage of diode

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- Forward DC Current: approx. 1mA

- Reversed DC Voltage: approx.2.8V

- Overload Protection: 250V DC or rms AC

DC Current

Range Resolution Accuracy
200μA 0.1μA ±（1.0% of rdg + 2 digits）

2mA

0.001mA

20mA 0.01mA ±（1.5% of rdg + 2 digits）

200mA 0.1mA

10A 0.01A ±（3.0% of rdg + 2 digits）

- Overload Protection: μA, mA ranges: F 200mA/250V fuse (quick
acting), 10A range: unfused.

- Max. Input Current: mA Jack: 200mA, 10A Jack: 10A

- voltage drop: 200mV

Resistance

Range Resolution Accuracy

200Ω 0.1Ω ±（1.0% of rdg + 3 digits）

2kΩ 0.001kΩ

20kΩ 0.01kΩ ±（1.0% of rdg + 2 digits）

200kΩ 0.1kΩ

2MΩ 0.001MΩ

- Open Circuit Voltage: 2.8V

- Overload Protect i o n: 25 0V DC or rms AC

Transistor hFE

Range

Function

hFE Display: read approximate hFE value (0-

1000) of

transistor under test (ALL TYPE)

- Base Current: approx. 2µA，Vce: approx. 2.8V

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OPERATING INSTRUCTION

● DATA HOLD

If you need data hold when m easuring, you can press on “ H” butto n, it
will hold the reading; if you press the button again, data hold will not
continue.

● PREPARATIO N FOR MEASUREME NT

- Turn on t he m et er. If the battery voltage is less than 3.6V, display will
show “

”, the battery should be changed at this time.

- The “

- Select a f unct i o n and a r ang e f or the it em to be measured by rotating
the transform switch to the selected position. When the value scale
to be measu red is unk nown beforeha n d, set t he ra n ge sel ec to r at t he
highest position.

” besides the input jack shows that the input voltage or
curren t should b e less th an spec ificati on on the st icker of the met er
to protect the inner circuit from damaging.

- When connecting, first connect to the public testing line, then to the
electriferous testing line. When you remove it, you should remove
the elecriferous one first.

● MEASURING DC VOLTAGE

You can’t test vol tage which more than 1000V DC, it’s possible
to show higher voltage, but it may destroy the inner circuit.

WARNING

Pay attention not to get an electric shock when measuring

high voltage.

- Conn ect th e black t est le ad to th e COM jack a nd the re d test le ad to
the V jack.

- Set the transform switch at the

V range position.

- Connect test leads across the source or load under measurement.

- You can get a reading from LCD display. The polarity of the red test
lead connection will be indicated.

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NOTE:

- When only the figure ‘1’ is displayed, it indicates overrange situation
and the higher range has to be selected.

- When the value scale to be measured is unknown beforehand, set
the range selector at the highest position.

● MEASURING AC VOLTAGE

- Conn ect th e black t est le ad to th e COM jack a nd the re d test l ead to
the V jack.

- Set the transform switch at the V range position.

- Connect test leads across the source or load under measurement.

- You can get reading from LCD.

You can’t input a voltage which is more than 750V rms AC, it’s
possible to show higher vol tage, but it’s may destroy the inner
circuit.

WARNING

Pay attention not to get an electric shock when measuring

voltage.

NOTE:

- When only the figure ‘1’ is displayed, it ind icat es over range situation
and the higher range has to be selected.

- When the value scale to be measured is unknown beforehand, set
the range selector at the highest position.

● MEASURING DC CURRENT

Shut down the power of the tested circuit, then connect the

meter with the circuit for measurement.

WARNING

- Conn ect th e black t est le ad to th e COM jack a nd the re d test l ead to
the mA jack for a maximum of 200mA current. For a maximum of
10A, move the red lead to the 10A jack.

- Set the transform switch at the

A range position.

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- Connect test leads in series with the load under measurement.

- You can get reading from LCD. The polarity of red test lead will be
indicated.

NOTE:

- When only the figure ‘OL’ is displayed, it indicates over range
situation and the higher range has to be selected.

- When the value scale to be measured is unknown beforehand, set
the range selector at the highest position.

- “

” means the socket of INPUT maximum current is 200mA, over
current will destroy the fuse. 10A’s maximum current is 10A, no fuse
protection.

● MEASURING RESISTANCE

When measuring in-circuit resistance, be sure the circuit under
test has all power removed and that all capacitors have been
discharged fully.

WARNING

- Conn ect th e black t est le ad to th e COM jack a nd the re d test le ad to
the Ω jack.

- Set the transform switch at the Ω range position.

- Connect test leads across the re sistance under measurement.

- You can get reading from LCD.

NOTE:

- When o nl y the f igu re ‘1’ is dis play ed, it ind icat es over range situation
and the higher range has to be selected.

- When the input is not connected, i.e. at open circuit, the figure ‘1’ will
be displayed for the over range condition.

● TESTING DIODE

- Conn ect th e black t est le ad to th e COM jack a nd the re d test le ad to
the

Ω jack. (The polarit y of red lead is “+”)

- Set the transform switch at the

range position.

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- Connect the red lead to the anode, the black lead to the cathode of
the diode under testing.

- You can get reading from LCD.

NOTE:

- The meter will show the approximate forward voltage drop of the
diode.

- If the lead connection is reversed, only figure ‘1’ will be displayed.

- When the input is not connected, i.e. at open circuit, the figure ‘1’ will
be displayed.

• TESTING TRANSISTOR

- Set the transform switch at the hFE range position.

- Identify whether the transistor is NPN or PNP type and i nse rt emit ter,
base and collector leads into the proper holes of the transistor on the
socket for testing.

- You can get reading from LCD.

MAINTENANCE

● BATTERY REPLACEMENT

Before attempting to open the battery cover of the meter, be

sure that test leads have been disconnected from
measurement circuit to avoid electric shock hazard.

WARNING

- Loosen the screw fixing the battery cover and remove it.

- Replace the exhausted battery with a new one.

- Replace the battery cover.

● FUSE REPLACEMENT

- Loosen the screw fixing the battery cover and remove it.

- Replace the blown fuse with ratings specified.

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- Replace the battery cover.

Before attempting open the battery cove r of the meter, be sure
that test leads have been disconne

cted from measurement

circuit to avoid electric shoc k hazar d.

WARNING

For protection against fire, replace fuses only with specified
ratings: F 200mA/250V (quick acting).

● TEST LEADS REPLACEMENT

Full compliance with safety standards can be guarant eed only
if used with the test leads supplied. If ne cessary, they must be
replaced with the same model or same el ectri c rati ngs. Ele ctric
ratings of the test l eads: 1000V 10A .

WARNING

You must replace the test leads if the lead is exposed.

ACCESSORIES

⑴ Test Leads: Electric Rating s 1000 V 1 0A one piece
⑵ Battery:1.5V, AAA three pi eces

⑶

Instruction Manual one piece

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