MT870
True RMS Digital Multimeter
INTRODUCTION
The MT870 multimeter is a slim sized, portable, robust drop proof digital
multimeter. The MT870 has a 2000 count digit LCD monitor with large 25mm
digits that offer clear and easy reading. The circuitry design is centred on
large-scale IC A/D converters in conjunction with an over-load protection
circuit, the meters offers excellent performance and is ideal for a handy
digital multimeter.
The meters can be used to measure DC & AC True RMS voltage, DC & AC
True RMS current, resistance, battery test, diode test and audible continuity.
If the equipment is used in a manner not specified by the manufacturer, the
protection provided by the equipment may be impaired.
This Equipment Conforms to UL STD. 61010-1, 61010-2-030 and 61010-2-
033; Certified to CSA STD. C22.2 NO. 61010-1, 61010-2-030 and 61010-2-
033.
1.
LCD display: 3 1/2 digits LCD display, full function symbol display.
2.
SELECT
key: This key works on the " " range, press the key to
choose diode or continuity test, on the current range, change to DC or AC.
If you press and hold the “
SELECT
” key to power on, “Auto Power Off ”
function will be disabled. “
3.
RANGE
Key: Press the “
RANGE
” key, the meter enters manual range
mode, press it more than 2 seconds again, return to auto mode.
4.
MAX/MIN
key: Press the “
MAX/MIN
” key to lock
MAX
or
MIN
value,
and the “
MAX
” or “
MIN
” sign will appear on the display, press it more
than 2 seconds again to exit.
5.
D.HOLD
key: Press the “
D.HOLD
” key to lock display value, and the “DH”
sign will appear on the display, press it again to exit.
6.
RESET
Key: Press the “
RESET
” key to reset the meter.
7.
Rotary Switch
: Use this switch to select functions and ranges.
8.
COM
: COM “-” Input Jack
9.
10A
: 10A Input Jack
10.
AΩmA
: VµA, mA,/BATT/
Ω
/ Input Jack
11. Meter casing
12. Protective casing
Safety Information
1.
The meter is designed according to IEC61010-1 concerning
electronic measuring instruments with an over-voltage
category 600V (CAT II) or 300V (CAT III) and pollution 2.
2.
Follow all safety and operating instructions to ensure that
the meter is used safely and is kept in good operating
condition.
3.
Safety symbols:
Important safety information, refer to the operating
manual.
Dangerous voltage may be presence.
Double insulation (protection Class II)
Special Cautions for Operation
1.
The meters can be safe only according to standard p
rocedures when used
in conjunctions with the supplied test leads. Please replace damaged test
leads with the same electric specifications.
2.
To avoid risk of electric shock, do not use the meter if the c asing has been
opened.
3.
The range switch should be right position before making a m
easurement.
4.
To avoid electric shock and damaging the instrument, the i nput signals
must not exceed the specified limits.
5.
When measuring TV set or switched power, attention s hould b
e paid to the
possible pulses that may cause damage to the circuitry.
6.
Range switch position must not be changed at random d
uring
measurement.
7.
Take caution against shock in the course of measuring v
oltage higher than
DC 60V & AC 30V.
8.
Protection fuse should be replaced only with same type a
nd same
specification.
9.
Verity the multimeter's operation by measuring a known voltage.
10. After operation is finished, set function switch at OFF to save battery
power.
11. If the meter is without usage for long time, take out the battery to avoid
damage by battery leakage.
General Specifications
1.
M
ax Voltage between input terminal and Earth Ground: C
AT II 600V or
CAT II 300V.
2.
Over-range Indication: display “OL” for the significant digit.
3.
Automatic display of negative polarity “-”.
4.
Low Battery Indication: “
” displayed.
O L
5.
Display: 3 1/2 digit LCD with a max. reading of 1999.
6.
Auto range & manual range control.
7.
Auto Power Off: When measurement exceeds 15 minutes without switching
mode and pressing key, the meter will switch to standby mode. Press any
key to exit standby mode. When restart the system, press and hold
SELECT
key to disable auto power off.
8.
Fuse protection: 250mA/600V Fast Fuse, 10A/600V Fast Fuse.
9.
Power supply: 1.5V×2 “AA” R6P battery
10. Operating Temp.:
to 40
(relative humidity <85%)
0°C
°C
11. Storage Temp.: -10
to 50
(relative humidity <85%)
°C
°C
12. Guaranteed precision Temp.: 23±5
(relative humidity <70%)
°C
13. Dimension: 150 x 100 x 36mm
14. Weight: approx. 250g (including battery)
DC Voltage
Range
Resolution
Accuracy
200mV
0.1mV
2V
1mV
±(0.5% of rdg + 2 digits)
20V
10mV
200V
100mV
600V
1V
±(0.8% of rdg + 2 digits)
* Impedance: 10MΩ, More than 100MΩ on 200mV range
* Overload protection: 600V DC or AC rms
Range
Resolution
Accuracy
2V
1mV
±(0.8% of rdg + 3 digits)
20V
10mV
200V
100mV
600V
1V
±(1.2% ofrdg + 3 digits)
AC Voltage
* AC True RMS
* Impedance: 10MΩ
* Overload protection: 600V DC or AC rms
* Frequency Range: 40 to 2kHz
Range
Resolution
Accuracy
200
μ
A
0.1
μ
A
2000
μ
A
1
μ
A
±(1.2% of rdg + 2 digits)
20mA
10
μ
A
200mA
100
μ
A
2A
1mA
±(2.0% of rdg + 3 digits)
10A
10mA
DC Current
* Overload protection: 250mA/600V Fast Fuse10A/600V
Fast Fuse, 10A up to 10 seconds
Testing Specifications
°C
°C
Accuracy is specified for a period of year after calibration and at 18
to 28
°F
°F
(64
to 82
) with relative humidity to 70%.
Panel Layout
1
2
3
4
5
6
7
8
9
10
11
12