Unit UT8806E User manual

User’s Manual
UT8806E Desktop Digital Multimeter

User’s Manual UT8806E Desktop Digital Multimeter
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Copyright and Statement
Preface
Dear User,
Thank you for choosing this brand new UNI-T instrument. In order to use this instrument
safely and correctly, please read this manual thoroughly, especially the Safety Requirements
part.
After reading this manual, it is recommended to keep the manual at an easily accessible place,
preferably close to the device, for future reference.
Copyright
Copyright is owned by Uni-Trend Technology (China) Co., Ltd.
The instrument has a warranty period of three years from the date of purchase. If the
instrument is damaged due to improper operation by the user during the warranty period, the
maintenance fee and the costs caused by the maintenance shall be borne by the user, and the
instrument shall be maintained by the company for life.
If the original purchaser sells or transfers the product to a third party within three years from
the date of purchase of the product, the warranty period of one year shall be from the date of
the original purchase from UNI-T or an authorized UNl-T distributor. Power cords,
accessories and fuses, etc. are not included in this warranty.
If the product is proved to be defective within the warranty period, UNI-T reserves the rights
to either repair the defective product without charging of parts and labor, or exchange the
defected product to a working equivalent product (determined by UNI-T). Replacement parts,
modules and products may be brand new, or perform at the same specifications as brand new
products. All original parts, modules, or products which were defective become the property
of UNI-T.
The "customer" refers to the individual or entity that is declared in the guarantee. In order to
obtain the warranty service, “customer “must inform the defects within the applicable
warranty period to UNI-T, and perform appropriate arrangements for the warranty service.

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The customer shall be responsible for packing and shipping the defective products to the
individual or entity that is declared in the guarantee. In order obtain the warranty service,
customer must inform the defects within the applicable warranty period to UNI-T, and
perform appropriate arrangements for the warranty service. The customer shall be
responsible for packing and shipping the defective products to the designated maintenance
center of UNI-T, pay the shipping cost, and provide a copy of the purchase receipt of the
original purchaser. If the products is shipped domestically to the purchase receipt of the
original purchaser. If the product is shipped to the location of the UNI-T service center, UNI-T
shall pay the return shipping fee. If the product is sent to any other location, the customer
shall be responsible for all shipping, duties, taxes, and any other expenses.
Trademark
UNI-T is the registered trademark of Uni Trend Technology (China) Co., Ltd.
File Version
UT8806E20230718-V1.00
Statement
UNI-T products are protected by patent rights in China and foreign countries, including
issued and pending patents.
UNI-T reserves the rights to any product specification and pricing changes.
UNI-T reserves all rights. Licensed software products are properties of Uni-Trend and its
subsidiaries or suppliers, which are protected by national copyright laws and international
treaty provisions. Information in this manual supersedes all previously published versions.

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General Safety Summary
The instrument is designed to meet the safety requirements of GB4793 safety requirements
for electronic measuring instruments, IEC/EN61010-1, EN61010-2-030 pollution class 2,
overvoltage CATI 1000V, CATII 300V and double Insulation; and complies with the IP65
standard for waterproofing and dustproofing.
This manual contains information and warnings that must be observed to keep the instrument
in a safe condition and ensure safe operation.
Use Proper Power Cord. Use only the power cord specified for this product and certified for
the country of use, and make sure that no metal parts are exposed and the insulation is
broken.
Ground the Product. This product is grounded through the grounding conductor of the power
cord. To avoid electric shock, the grounding conductor must be connected to earth ground.
Before making connections to the input or output terminals of the product, ensure that the
product is properly grounded. The signal ground on the rear panel of the product is the same
as the ground potential.
Check the Wire. Check if the insulation of the test lead is damaged or if the lead is exposed;
check if the test lead is on, if there is any damage to the lead, replace it before using the
instrument.
Observe All Terminal Ratings. The voltage applied between the terminals or any one of the
terminals and the grounding point must not exceed the rated value indicated on the
instrument.
Do Not Touch Live Part. Do not touch exposed connection wires, unused inputs or circuits
being measured while the instrument is in use. When measuring voltages higher than 60V DC
or 30V AC, be sure to exercise caution and remember to keep your fingers away from the
meter's guard position to prevent electric shock.
Do Not Operate with Suspected Failures. If you suspect that this product is malfunctioning,
contact UNI-T's authorized service personnel for testing. Any maintenance, adjustment, or
replacement of parts on this product must be performed by UNI-T authorized service
personnel.
Avoid Exposed Circuitry. Do not touch exposed connections and components when power is
present.
Do Not Operate Without Covers. Do not operate this product with covers or panels removed,
and do not adjust the internal circuit.
Use Proper Fuse. Use only the fuse type and rating specified for this product.
Use Proper Over-voltage Protection. Make sure that no overvoltage (e.g. caused by lightning)
reaches the product, as this may result in electric shock to the operator.

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Avoid Severe Environment. Avoid using the instrument in high temperature, high humidity,
flammable, explosive and strong electromagnetic environments.
Disconnect the Power Supply. Before testing the impedance, conduction, diodes, or
capacitance, disconnect power and discharge all high voltage capacitors.
Input Terminal Protection Limit
1. Main Input Terminal (HI and LO)
HI and LO input terminals are used for voltage, impedance, capacitance, continuity,
frequency and diode test measurements. These two terminals define the following two
protection limits.
1) Protection limit from HI to LO, which is 1000 VDC or 750 VAC. This is also the
maximum voltage that can be measured. This limit can also be expressed as a
maximum of 1000 Vpk.
2) Protection limit from LO to ground. The LO input terminal can be safely "floated" to a
maximum of 500 Vpk with respect to ground. The protective limit of the HI terminal is
a maximum of 1000 Vpk with respect to ground. Therefore, the sum of the "floating"
voltage and the measured voltage must not exceed 1000 Vpk.
2. Sampling Terminal (HI sense and LO sense)
HI Sense and LO Sense terminals are used for four-wire impedance test and
measurement. These two terminals define the following two protection limits.
1) Protection limit from HI Sense to LO Sense. Protection limit of HI Sense and LO
Sense are 200 Vpk.
2) Protection limit from LO Sense to LO. Protection limit of LO Sense and LO are 2 Vpk.
3. Current Input Terminal (mA and A)
1) The mA and LO terminal are used to measure the current test below 200mA. The rear
panel fuse provides a maximum protection limit of 250mA for current flowing through
the mA terminal.
2) The A and LO terminal are used to measure the current test from 200mA to 10A. The
rear panel fuse provides a maximum protection limit of 10A for current flowing
through the A terminal.
Notes
The voltage at the current input terminal is about the same as the voltage at the LO terminal.
To maintain good protection, this fuse can only replace with a fuse of the specified type and
rating.
IEC Measurement Category II Overvoltage Protection
To avoid the risk of electric shock, the UT8806E digital multimeter provides overvoltage
protection for electric mains connections that meet both of the following conditions.
1. The HI and LO input terminals are connected to the electric mains under Measurement
Category II conditions (described below).
2. The maximum line voltage of the electric mains is 300 VAC.

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Warnings
IEC measurement category II includes electrical installations connected to the mains via a
socket on a branch circuit. These devices include most small appliances, test equipment, and
other devices plugged into branch circuit sockets.
Measurement of UT8806E Digital Multimeter
The HI and LO input terminals are connected to the electric mains (up to 300VAC) in these
devices, or to branch circuit socket. However, the HI and LO input terminals of the UT8806E
cannot be connected to the electric mains in permanently installed electrical devices, such as
main breaker panels, sub-panel breakout boxes, or permanently wired motors. These devices
and circuits are susceptible to overvoltage that exceed the protection limits of the UT8806E.
Notes
The voltage above 300VAC can only be measured in circuits that disconnected from the
electric mains. However, transient overvoltage also exist in circuits when disconnected from
the electric mains, and the UT8806E can safely withstand incidental transient overvoltage up
to 2500 Vpk.
Do not use this device to measure circuits where transient overvoltage may exceed this level.
Safety Term and Symbol
Safety Symbol
Danger
It indicates possible danger of electric shock, which may
cause personal injury or death.
Warning
It indicates that you should be careful to avoid personal injury
or product damage.
Caution
It indicates possible danger, which may cause damage to this
device or other equipment if you fail to follow a certain
procedure or condition. If the “Caution” sign is present, all
conditions must be met before you proceed to operation.
Note
It indicates potential problems, which may cause failure of this
device if you fail to follow a certain procedure or condition. If
the “Note” sign is present, all conditions must be met before
this device will function properly.
AC
Alternating current of device.
DC
Direct current of device
Grounding
Frame and chassis grounding terminal
Grounding
Protective grounding terminal

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Grounding
Measurement grounding terminal
Power
Supply
Standby power supply: when the power switch is turned off,
this device is not completely disconnected from the AC power
supply.
CAT I
Secondary electrical circuit connected to wall sockets through transformers
or similar equipment, such as electronic instruments and electronic
equipment; electronic equipment with protective measures, and any
high-voltage and low-voltage circuits, such as the copier in the office.
CAT II
Primary electrical circuit of the electrical equipment connected to the indoor
socket via the power cord, such as mobile tools, home appliances, etc.
Household appliances, portable tools (e.g. electric drill), household sockets,
sockets more than 10 meters away from CAT III circuit or sockets more than 20
meters away from CAT IV circuit.
CAT III
Primary circuit of large equipment directly connected to the distribution board
and circuit between the distribution board and the socket (three-phase
distributor circuit includes a single commercial lighting circuit). Fixed
equipment, such as multi-phase motor and multi-phase fuse box; lighting
equipment and lines inside large buildings; machine tools and power
distribution boards at industrial sites (workshops).
CAT IV
Three-phase public power unit and outdoor power supply line equipment.
Equipment designed to “initial connection”, such as power distribution system
of power station, power instrument, front-end overload protection, and any
outdoor transmission line.
Certification
CE indicates a registered trademark of EU.
Certification
UKCA indicates a registered trademark of British.
Certification
ETL indicates a registered trademark of Intertek.
Waste
This product complies with the marking requirements of WEEE Directive
(2002/96/EC). This additional label indicates that this electrical / electronic
product must not be discarded in household waste.
EFUP
This environment-friendly use period (EFUP) mark indicates that dangerous or
toxic substances will not leak or cause damage within this indicated time
period. The environment-friendly use period of this product is 40 years, during
which it can be used safely. Upon expiration of this period, it should enter the
recycling system.

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UT8806E Introduction
The UT8806E is a 6½ -digit desktop digital multimeter with a maximum display of 2,000,000,
featuring high accuracy, versatility, and full automation. In addition to the most basic
measurements, it has various mathematical operation function, and supports capacitance,
temperature and other measurements.
The UT8806E is equipped with a 4.3-inch TFT display with 480*272 resolution and supports
LAN, USB, RS-232C and GPIB (option), making it suitable for use as a laboratory work meter
and for high-precision measurements in automated test systems.
Main Features
Real 6½ -digit resolution
Minimum integral time: 0.006PLC
Dual display function can present two features of the same input signal at the same time
DC voltage range of 200mV ～1000V
DC current range of 2μA ～10A
True-RMS, AC voltage range of 200mV ～750V
True-RMS, AC current range of 200μA ～10A
Impedance range of 20Ω ～1GΩ, 2-wire, 4-wire impedance measurement
Capacitance range of 2nF～200mF
Frequency measuring range of 20Hz ～1MHz
Continuity and diode test
Temperature test, built-in thermocouple cold-end compensation
Multiple mathematical operation: maximum, minimum, average, standard deviation,
Pass/Fail, dBm, dB, relative measurement, histogram, tendency chart and bar chart
USB is for saving data and configuration
Support USB, GPIB, RS-232C and LAN interface; support USB-TMC, IEEE 488.2, VXI11 and
SCPI
Compatible with the newest mainstream multimeter SCPI command set
Record and save the historical measured results
32Gb NANDFLASH capacity for save the system configuration and test data
Chinese/English menu and on-line help system
PC control software
Support global mains voltage

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About this Manual
This manual provides information on the operation of the UT8806E digital multimeter and
includes the following chapters.
Chapter 1 Quick Guide
This chapter is to guide you through the front/rear panel and user interface and get the
UT8806E digital multimeter ready.
Chapter 2 Panel Operation
This chapter is to introduce various functions and operations of multimeter in detail.
Chapter 3 Measurement Guide
This chapter provides information on how to eliminate the possible errors in measurement to
obtain accurate measured results.
Chapter 4 Applications
This chapter provides detailed information on using the UT8806E to make electrical
measurements.
Chapter 5 Troubleshooting
This chapter provides detailed information of system prompt and common troubleshooting.
Chapter 6 Appendices
This chapter provides details of attachments, warranty and service and support information.

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Table of Contents
Copyright and Statement .......................................................................................2
General Safety Summary........................................................................................4
Safety Term and Symbol ........................................................................................ 6
UT8806E Introduction............................................................................................ 8
About this Manual ..................................................................................................9
Chapter 1 Quick Gide................................................................................................1
General Inspection..........................................................................................2
Adjusting Handle............................................................................................. 3
External Dimension.........................................................................................3
Front Panel.....................................................................................................4
Rear Panel ......................................................................................................6
Power On........................................................................................................8
User Interface.................................................................................................8
Built-in Help ...................................................................................................9
Chapter 2 Panel Operation.....................................................................................10
Measurement Configuration...........................................................................10
Range Selecting ..................................................................................... 11
Integral time Time and Resolution...........................................................13
Input Impedance.....................................................................................15
Automatic Zeroing..................................................................................16
Low-frequency Filter ..............................................................................17
Short-circuit Resistance.........................................................................18
Diode Break-over Voltage .......................................................................19
Measuring Interval ..................................................................................19
Basic Measurement ......................................................................................20
DC Voltage Measurement.......................................................................20
DC Current Measurement....................................................................... 22
AC Voltage Measurement....................................................................... 24
AC Current Measurement....................................................................... 27
2-wire Resistance Measurement............................................................ 30
4-wire Resistance Measurement............................................................ 32
Capacitance Measurement .................................................................... 35
Frequency Measurement ....................................................................... 37
Signal Period Measurement ................................................................... 39
Continuity Measurement.........................................................................41
Diode Measurement............................................................................... 43
Temperature Measurement ................................................................... 45
Auxiliary System Function............................................................................. 47
Storage and Restore.............................................................................. 48
Management File ....................................................................................51

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I/O Configuration ................................................................................... 52
Self-inspection...................................................................................... 54
System Setting...................................................................................... 55
Firmware Update................................................................................... 57
Sampling Setting .......................................................................................... 58
Automatic Trigger ................................................................................. 59
Single Trigger........................................................................................ 60
External Trigger......................................................................................61
Enable Trigger....................................................................................... 62
Help System ................................................................................................. 62
Mathematical Operation................................................................................ 64
Statistical Operation.............................................................................. 65
Limits Operation.................................................................................... 66
dBm Operation ...................................................................................... 68
dB Operation ......................................................................................... 69
Relative Operation ................................................................................. 70
Dual Display ...................................................................................................71
Display Mode ................................................................................................ 72
Digital.................................................................................................... 72
Bar Figure ............................................................................................. 73
Tendency Figure.................................................................................... 74
Histogram Figure................................................................................... 75
Hold Measurement................................................................................. 77
Chapter 3 Measurement Guide ............................................................................. 78
Load Error (DC-Voltage) ................................................................................ 78
True RMS AC Measurement ........................................................................... 79
Load Error (AC-Voltage) .................................................................................81
Chapter 4 Applications......................................................................................... 82
Example 1 Reading Statistics......................................................................... 82
Example 2 Eliminate Test Lead Impedance Error........................................... 83
Example 3 dBm Measurement ....................................................................... 84
Example 4dB Measurement........................................................................... 85
Example 5 Limits Measurement .................................................................... 86
Example 6 Hold Measurement ....................................................................... 88
Example 7 Thermocouple Setting and Measurement...................................... 89
Chapter 5 Troubleshooting....................................................................................91
Chapter 6 Appendix.............................................................................................. 92
Appendix A UT8806E Accessories ................................................................. 92
Appendix B Warranty Overview...................................................................... 92
Appendix C Maintenance and Cleaning .......................................................... 92
Appendix D Contact Us.................................................................................. 93

Chapter 1 Quick Gide
This chapter is to introduce the preparation of the UT8806E digital multimeter and simply
introduce the front/rear panel and display screen.
General Inspection
Adjusting Handle
External Dimension
Front Panel
Rear Panel
Power-on
User Interface
Test Connection
Help System

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General Inspection
1. Check for damage caused by transportation
If you find that the packing carton or protective foam cushion is badly damaged, keep it
until the complete unit and accessories have passed the electrical and mechanical tests.
2. Checking accessories
The details of the supplied accessories are described in Appendix A in Chapter 6 of this
manual. You can refer to these instructions to check for missing accessories.
If you find that an accessory is missing or damaged, contact the UNI-T distributor
responsible for your business or the local UNI-T office.
3. Checking the complete unit
If you find that the instrument is visually damaged, that the instrument is not working
properly, or that it fails a performance test, contact the UNI-T distributor responsible for
the operation or the local UNI-T office.
If the instrument is damaged due to transportation, please retain the packaging. Notify
the shipping department and the UNI-T distributor. UNI-T will arrange for repair or
replacement.

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Adjusting Handle
The multimeter’s handle can adjust to three positions by appropriate strengths, as shown in
Figure 1-1, 1-2 and 1-3.
Figure 1-1 Adjusting Handle
Figure 1-2 Holding Down Position Figure 1-3 Moving Position
External Dimension
Figure 1-4 External Dimension

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Front Panel
The UT8806E digital multimeter provides the user with a simple and clear front panel. These
controls are displayed in logical groupings, and basic operations can be performed by simply
selecting the appropriate button, as shown in Figure 1-5.
Figure 0–1 Front Panel
1：LCD
The 4.3-inch TFT display with a resolution of 480*272, showing the menu and
measurement parameter settings, the system status and prompt messages.
2：USB
This interface allows storing the current instrument status or measurement data to an
external device, as well as reading stored instrument status or upgrade files from an
external device when needed.
3：Power Button
Short press/long press the power button to turn on/off the multimeter. The UT8806E has
power memory function, which is restore to the state before power off after power on.
4：Menu Operation Key
Press any one of soft key to activate the menu.
5：Measurement and Auxiliary Function Key
DC voltage measurement or DC current measurement (secondary function)

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AC voltage measurement or AC current measurement (secondary function)
2-wire impedance measurement or 4-wire impedance measurement (secondary function)
Capacitance measurement or match with probe temperature measurement (secondary
function)
Continuity measurement or diode measurement (secondary function)
Signal frequency measurement or signal period measurement (secondary function)
Dual display function or auxiliary system function (secondary function)
Sampling setting or auxiliary help system (secondary function)
Mathematical operation or storage function (secondary function)
Start/stop or return function
Manual trigger or reading hold function
Secondary function or key switching
6：Range and Direction Key
Automatic/manual range
Set the parameter/move the cursor/page turning/range switching
Configure measurement parameter/Select cursor position
7：Signal Input
The signal to be measured is connected to the multimeter via this input terminal. The
measurement connection method varies for different measurement objects, so please
refer to the description in "Measurement Connection" for details.
8：Front/rear Input Switch
Select the input terminal, when the switch key is pressed, the measurement circuit
connects to the input terminal on the rear panel; when the switch key is pop-up, the
measurement circuit connects to the input terminal on the front panel. Be sure to
disconnect the input signal when switching.

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Rear Panel
The rear panel of the UT8806E digital multimeter provides multiple ports, including USB
Device, RS-232C, LAN and GPIB (option) as shown in Figure 1-6.
Figure 0–2 Rear Panel
1：Power Input Port
This multimeter can input four sizes of AC power. Use the power cord provided with the
accessory to connect AC power to the multimeter through this jack. Note, before
connecting AC power, select the correct voltage level (voltage selector inside the socket).
Power Fuse
The multimeter has built-in power fuse when out of the factory. This fuse is a slow blow,
explosion proof, 250mA,5x20mm fuse.
To replace the fuse, follow the steps in below.
1) Disconnect the power of the multimeter.
2) Use a screwdriver to pry open the fuse compartment (on the top) and pull out the fuse
holder.
3) Select the correct voltage level by dialing the voltage selector according to the voltage
range indicated by the socket.
4) Replace the fuse with the specified size.
5) Reinstall the fuse holder into the slot.
6) Close the fuse compartment.

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Voltage Selector Turnplate
UT8806E supports 100V~240V frequency of 50Hz, 60Hz, 400Hz industrial AC mains, please
confirm the AC power specification you are using, and dial the voltage turnplate according
to the label on the left side of the jack to select the correct voltage scale.
2：RS-232 Communication Port
RS-232 serial communication port of UT8806E is 9-pin male socket, which on the rear
panel. The pin definition is as follow.
Pin2-----RXD
Pin3-----TXD
Pin5-----GND
3：RJ45 Internet Communication Port
The UT8806E is equipped with a RJ45 interface on the rear panel, which supports VXI-11
protocol. Through this interface, the multimeter can connect to the LAN for remote
control. For the specific settings, please refer to Chapter 2 Panel Operation-Auxiliary
System Functions-I/O Port Configuration.
4：USB-DEVICE Port
The UT8806E is equipped with a D-type USB 2.0 port on the rear panel, which supports
USB-TMC protocol for communication with a PC. Using the upper computer software to
control the multimeter.
5：GPIB Port
For the specific settings, please refer to Chapter 2 Panel Operation-Auxiliary System
Functions-I/O Port Configuration.
6：VMC Signal Output Port
The UT8806E outputs a pulse with a width of about 1μs and an amplitude of 5V from this
port every time it completes a sampling.
7：Ext TRIG Signal Input Port
The UT8806E supports external trigger switching, including the rising edge, falling edge
and level trigger.
8：Signal Input
There are 5 input terminal in total, arranged in the same order and the same electrical
parameters as the previous input terminal.
9：Lock Hole

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If necessary, you can lock the digital multimeter in a fixed position using a safety lock
(please purchase your own).
Operating Method
Insert the key along with the vertical direction to the lock hole on the rear panel and
clockwise rotation to lock the digital multimeter and then plug out the key.
10：Ground Terminal
Ground the outer shell of UT8806E multimeter through a metal wire.
Power On
Please follow the following steps to turning power on.
1. Adjusting AC voltage selector according to the regional power standard to 100 (95～110V,
45～440Hz, AC), 120 (110～132V, 45～440Hz, AC) or 230 (215～240V, 45～440Hz, AC), 240
(225～265V, 45～440Hz, AC).
2. Using the power cable attached with the meter to connect to AC.
3. Observing the power indicator turning to red.
4. Press the power button on the front panel, wait for seconds, the instrument will start to
display.
Note: The character with【】represents the six software menu below the screen.
User Interface
Single display
Figure 0–3 Single Display

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Dual Display
Figure 0–4 Dual Display
Built-in Help
If you need to get the built-in help information of this product, press [Shift] + [Acquire] to
enter the help system at first, then press the arrow keys to select the desired help item, and
finally press [OK] to view the corresponding help information.
Built-in Help System
1. Basic Measurement
2. Temperature Measurement
3. Capacitance Measurement
4. Mathematical Operation
5. Dual Display
6. Storage Function