multicomp pro MP730889 User manual

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Digital Multimeter User Manual
MP730889

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Table of Contents
1.Safety Information......................................................................................................1
Safety Terms and Symbols .................................................................................................. 1
General Safety Requirements.............................................................................................. 2
Measurement Limits........................................................................................................... 3
Main Input Terminals Measurement Limits ..........................................................................................3
Current Input Terminal Measurement Limits ........................................................................................3
Measurement Category ...................................................................................................... 3
2.Quick Start..................................................................................................................5
General Inspection.............................................................................................................. 5
Dimensions......................................................................................................................... 5
Front Panel Overview ......................................................................................................... 6
Rear Panel Overview........................................................................................................... 8
User Interface..................................................................................................................... 9
Power On ..........................................................................................................................10
Measurement Connections ................................................................................................11
3.Functions and Operations .........................................................................................13
To Set the Range................................................................................................................13
Measurement Speed..........................................................................................................14
Basic Measurement Functions............................................................................................14
Measuring DC Voltage ........................................................................................................................14
Measuring AC Voltage ........................................................................................................................15
Measuring DC Current ........................................................................................................................16
Measuring AC Current ........................................................................................................................17
Measuring Resistance.........................................................................................................................19
Continuity Test ...................................................................................................................................20
Diode Test ..........................................................................................................................................21
Measuring Capacitance ......................................................................................................................22
Measuring Frequency and Period .......................................................................................................23
Measuring Temperature .....................................................................................................................24
Dual Display ......................................................................................................................26
Data Hold ..........................................................................................................................27
Math .................................................................................................................................27
Max/Min ............................................................................................................................................27
dB/dBm ..............................................................................................................................................27
Relative Value.....................................................................................................................................28
Data Record Function.........................................................................................................29
Manual Record ...................................................................................................................................29
Auto Record .......................................................................................................................................29
Utility Menu ......................................................................................................................31
Language ............................................................................................................................................31
Backlight.............................................................................................................................................31
Clock...................................................................................................................................................31
Default ...............................................................................................................................................31
Communication interface settings ......................................................................................................32

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4.Measurement Tutorial..............................................................................................33
Loading Errors (DC Voltage)................................................................................................33
True RMS AC Measurements..............................................................................................34
5.Troubleshooting .......................................................................................................35
6.Technical Specifications ............................................................................................36
7.Appendix ..................................................................................................................38
Appendix A: Enclosure .......................................................................................................38
Appendix B: General Care and Cleaning..............................................................................38
Appendix C: Line Fuse Replacement ...................................................................................39

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1. Safety Information
Safety Terms and Symbols
Safety Terms
Terms in this Manual. The following terms may appear in this manual:
Warning: Warning indicates the conditions or practices that could result in
injury or loss of life.
Caution: Caution indicates the conditions or practices that could result in
damage to this product or other property.
Terms on the Product. The following terms may appear on this product:
Danger: It indicates an injury or hazard may immediately happen.
Warning: It indicates an injury or hazard may be accessible potentially.
Caution: It indicates a potential damage to the instrument or other property might occur.
Safety Symbols
Symbols on the Product. The following symbol may appear on the product:
Direct current (DC)
Warning, risk of electric shock
Alternating current
(AC)
Caution, risk of danger (refer to
this manual for specific Warning
or Caution information)
Both direct and
alternating current Conforms to European Union
directives
Ground terminal
Chassis Ground
IEC Measurement Category I. The maximum measurable
voltage is 1000 Vpk in the HI -LO terminal.
IEC Measurement Category II. Inputs may be connected to
AC mains power (up to 600 VAC) under Category II
overvoltage conditions.
This product complies with the WEEE Directive (2012/19/EC)
marking equipment. The affixed product label indicates that
you must not discard this electrical/electronic product in
domestic household waste.

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General Safety Requirements
Before any operations, please read the following safety precautions to avoid any
possible bodily injury and prevent this product or any other products connected from
damage. In order to avoid any contingent danger, this product is only used within the
range specified.
Use Proper Power Cord. Use only the power cord supplied with the product and
certified to use in your country.
Product Grounded. This instrument is grounded through the power cord grounding
conductor. To avoid electric shock, the grounding conductor must be grounded. The
product must be grounded properly before any connection with its input or output
terminal.
Limit operation to the specified measurement category, voltage, or amperage
ratings.
Check all Terminal Ratings. To avoid instrument damage and the risk of electric
shock, check all the Measurement Limits and markers of this product. Refer to the
user's manual for the Measurement Limits before connecting to the instrument. Do
not exceed any of the Measurement Limits defined in the following section.
Do not operate without covers. Do not operate the instrument with covers or panels
removed.
Use Proper Fuse. Use only the specified type and rating fuse for this instrument.
Avoid exposed circuit. Do not touch exposed junctions and components when the
instrument is powered.
Do not operate if in any doubt. If you suspect damage occurs to the instrument,
have it inspected by qualified service personnel before further operations.
Use your instrument in a well-ventilated area. Inadequate ventilation may cause
increasing of temperature or damages to the device. Please keep well ventilated and
inspect the intake regularly.
Do not operate in wet conditions. In order to avoid short circuiting to the interior of
the device or electric shock, please do not operate in a humid environment.
Do not operate in an explosive atmosphere.
Keep product surfaces clean and dry.
Only the qualified technicians can implement the maintenance.

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Measurement Limits
The protection circuitry of the multimeter can prevent damage to the instrument and
protect against the danger of electric shock, when the Measurement Limits are not
exceeded. To ensure safe operation of the instrument, do not exceed the Measurement
Limits shown on the front panel, it is defined as follows:
Main Input Terminals Measurement Limits
The Input and COM Input terminals are used for voltage, resistance,
continuity, frequency (period), capacitance, diode, and temperature test measurements.
The Measurement Limit is defined for these terminals:
Input to COM Input Measurement Limit
The measurement limit from Input to COM Input is 1000 VDC or 750
VAC, which is also the maximum voltage measurement. This limit can also be
expressed as 1000 Vpk maximum.
Current Input Terminal Measurement Limits
The measurement limit from 10A input terminal to COM Input terminal is 10 A (DC
or AC).
The measurement limit from μA mAinput terminal to COM Input terminal is 600 mA
(DC or AC).
Note that the current input terminals will always be at approximately the same voltage
as the COM Input terminal.
Measurement Category
The safety rating of the multimeter:
1000 V, CAT I
IEC Measurement Category I. The maximum measurable voltage is 1000 Vpk in the HI -LO
terminal.
600 V, CAT II
IEC Measurement Category II. Inputs may be connected to AC mains power (up to 600
VAC) under Category II overvoltage conditions.
Measurement category definition
Measurement CAT I applies to measurements performed on circuits not directly
connected to the AC mains. Examples are measurements on circuits not derived from the
AC mains and specially protected (internal) mains- derived circuits.

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Measurement CAT II applies to protect against transients from energy-consuming
equipment supplied from the fixed installation, such as TVs, PCs, portable tools, and
other household circuits.
Measurement CAT III applies to protect against transients in equipment in fixed
equipment installations, such as distribution panels, feeders and short branch circuits,
and lighting systems in large buildings.
Measurement CAT IV applies to measurements performed at the source of the low-
voltage installation. Examples are electricity meters and measurements on primary over
current protection devices and ripple control units.

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2. Quick Start
General Inspection
After you get a new multimeter, it is recommended that you should make a check on the
instrument according to the following steps:
1. Check whether there is any damage caused by transportation.
If it is found that the packaging carton or the foamed plastic protection cushion has
suffered serious damage, do not throw it away first till the complete device and its
accessories succeed in the electrical and mechanical property tests.
2. Check the Accessories
The supplied accessories have been already described in the Appendix A: Enclosure
of this Manual. You can check whether there is any loss of accessories with
reference to this description. If it is found that there is any accessory lost or
damaged, please get in touch with our distributor responsible for this service or our
local offices.
3. Check the Complete Instrument
If it is found that there is damage to the appearance of the instrument, or the
instrument cannot work normally, or fails in the performance test, please get in
touch with our distributor responsible for this business or our local offices. If there is
damage to the instrument caused by the transportation, please keep the package.
With the transportation department or our distributor responsible for this business
informed about it, a repairing or replacement of the instrument will be arranged by
us.
Dimensions
200 mm

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Front Panel Overview
Figure 2-1 Front panel overview
Ite
m
Name
Description
1
LCD
Display the user interface
2
Menu selection
Keys
Activate the corresponding menu
86.5 mm
64 mm
2
4
5
1
7
3
6

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3
Measurement
Function Keys DC or AC voltage measurements
DC or AC current measurements
Resistance, continuity, and diode measurements
Capacitance measurements
Frequency/Period measurements
Temperature measurements
4
Power button
Turn on/off the multimeter.
5
Range/Direction
Keys
When the Range softkey is shown on the right menu, you
can press the key to switch between auto and
manual range. Press or keys to enable
manual range, and increase or decrease the measurement
range.
When setting a parameter, press to move the
cursor, press or keys to increase or decrease
the value.
6
Operation Keys
Run/Stop
Start or stop auto trigger. When the trigger is stopped, the
displayed data will be held.
Record
Access menus of manual record and auto record.
See page 29, Data Record Function.
Utility
Set the auxiliary system function, including Language,
Backlight, Clock, Default, and Serial port.
Math
Perform math operations (Max/Min, dB/dBm) on the
measurement results.
Dual
Press this key to display the function list on the right menu,
select a function, if the function is supported, the reading
will be displayed in the Vice Display.
7
Input Terminals
Signal input terminals, used for AC/DC current, voltage,
resistance, continuity, frequency (period), capacitance,
diode, and temperature test measurements.

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Rear Panel Overview
Figure 2-2 Rear panel overview

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Ite
m
Name
Description
1
Communication int
erface
connected to the computer via USB Device.
2
Line Fuse
The fuse rating is 250 V, F1AL. To replace the fuse, see page
39, Appendix C: Line Fuse Replacement.
3
AC Mains Input
AC mains input connector.
User Interface
Figure 2-3 User interface (Single display)
Trigger Mode
Reading
Range Function
Operation Menus
Unit
Status Icon
Secondary function
Primary function reading
Primary function
Trigger Mode
Status Icon
Display
Description
Trigger Auto trigger
Icon
Description
Auto record function is running
Manual record

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Figure 2-4 User interface (Dual display)
Power On
(1) Connect the instrument to the AC supply using the supplied power cord.
Warning:
To avoid electric shock, the instrument must be grounded properly.
(2) Press down the power button at the front panel, the screen shows the boot screen.

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Measurement Connections
After selecting the desired measurement function, please connect the signal (device)
under test to the multimeter according to the method below. To avoid instrument
damage, do not discretionarily switch the measurement function when measuring.
DC Voltage Measurement AC Voltage Measurement
DC Current Measurement
AC Current Measurement
DC Voltage
AC Voltage
DC Current
DC Current
AC Current
AC Current

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Resistance Measurement
Continuity Test
Diode Measurement Capacitance Measurement
Frequency/Period Measurement Temperature Measurement
Resistance
I
Open or
Closed Circuit
I
I
Forward Bias
Capacitance
AC Signal
I
Temp
Transducer

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3. Functions and Operations
To Set the Range
The instrument provides auto and manual range. In auto range, the multimeter selects a
proper range automatically according to the input signal; in manual range, you can use
the front panel key or menu softkey to set the range. The auto range can bring a lot of
convenience for users while the manual range provides higher reading precision.
1st Method: Use the front panel key to set the range.
When the Range softkey is shown on the right menu, you can press the key to
switch between auto and manual range. Press or keys to enable manual
range, and increase or decrease the measurement range.
2nd Method: Select the range in the measurement function menu.
Select auto range: In the measurement function menu, press the Range softkey, select
Auto.
Select manual range: In the measurement function menu, press the Range softkey, select
a range except Auto.
Note:
When the input signal exceeds the current range, "overload” will be displayed.
By default, the range is set to Auto at power-on or after a reset.
Auto range is recommended if you are not sure about the measurement range in order
to protect the instrument and obtain accurate data.

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Measurement Speed
The instrument provides three types of measurement speed:
"Low" speed is 4 reading/s; "Mid" speed is 16 reading/s; "High" speed is 65 reading/s.
In DCV, ACV, DCI, ACI and resistance measurements, the measurement speed is
selectable.
Basic Measurement Functions
Measuring DC Voltage
This section describes how to configure DC voltage measurements.
Operating Steps:
1. Enable the DCV measurement.
Press on the front panel to enter DCV measurement mode.
2. Connect the test lead.
3. Set the function.
Press the Function softkey to switch between V and mV.
4. Set the range.
Press the Range softkey to set the range. Auto range automatically selects the range
for the measurement based on the input.
Note:
1000 V input protection is available in all ranges.
10% over range for all ranges except 1000 V range.
If the reading exceeds 1050 V in 1000 V range, "overload" will be displayed.
DC Voltage

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5. Set the measurement speed.
Press the Speed softkey to switch between Low, Mid and High. See page 15 ”
Measurement Speed”.
6. Set the relative value.
Press the Rel softkey to turn on or off the relative operation. For relative operation,
the multimeter subtracts the pre-specified value of REL operation from the actual
measurement result and displays the result. See page 28, Relative Value.
Measuring AC Voltage
This section describes how to configure AC voltage measurements.
Operating Steps:
1. Enable the ACV measurement.
Press on the front panel, press it again to enter ACV measurement mode.
2. Connect the test lead.
3. Set the function.
Press the Function softkey to switch between V and mV.
4. Set the range.
Press the Range softkey to set the range. Auto range automatically selects the range
for the measurement based on the input.
Note:
750 V input protection is available in all ranges.
10% over range for all ranges except 750 V range.
If the reading exceeds 787.5 V in 750 V range, "overload" will be displayed.
5. Set the measurement speed.
Press the Speed softkey to switch between Low, Mid or High. See page 14,
“Measurement Speed “.
AC Voltage

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6. Set the relative value.
Press the Rel softkey to turn on or off the relative operation. For relative operation,
the multimeter subtracts the pre-specified value of REL operation from the actual
measurement result and displays the result. See page 28, Relative Value.
Measuring DC Current
This section describes how to configure DC current measurements.
Operating Steps:
1. Enable the DCI measurement.
Press on the front panel to enter DCI measurement mode.
2. Set the function.
Press the Function softkey to switch between A and mA.
3. When the Function is set as A, connect the test lead as below.
When the Function is set as mA, connect the test lead as below.
DC Current
DC Current

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4. Set the range.
Press the Range softkey to set the range. Auto range automatically selects the range
for the measurement based on the input.
Note:
The multimeter uses two kinds of fuses for current protection: A 10A fuse is built
into the 10A input terminal for overcurrent protection, and a 600mA fuse is built
into the uAmA input terminal for overcurrent protection.
10% over range for all ranges except 10 A range.
If the reading exceeds 10.5 A in 10 A range, "overload" will be displayed.
5. Set the measurement speed.
Press the Speed softkey to switch between Low, Mid and High. See page 14,
“Measurement Speed “.
6. Set the relative value.
Press the Rel softkey to turn on or off the relative operation. For relative operation,
the multimeter subtracts the pre-specified value of REL operation from the actual
measurement result and displays the result. See page 28, Relative Value.
Measuring AC Current
This section describes how to configure AC current measurements.
Operating Steps:
1. Enable the ACI measurement.
Press on the front panel, press it again to enter ACI measurement mode.
2. Set the function.
Press the Function softkey to switch between A and mA.
3. When the Function is set as A, connect the test lead as below.