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UT525/526 Operating Manual
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Contents
Item Page
I. Safety Precautions
II. Features
III. Specications
IV. Front View of the Instrument
V. Function of Keys and Dial Plate
VI. Testing Preparation
VII. Earth Testing
VIII. RCD Testing
IX. Voltage Testing
X. Insulation Resistance Testing
XI. Replace Battery
XII. Maintenance
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UT525/526 Operating Manual
Overview
UT525/UT526 is a digital multi-functional electric testing instrument adopting
new design and integrating large scale analog integrated circuit, digital circuit
and microprocessor chips, which can mainly test parameters of residual current
device (RCD), earth, insulation resistance, DCV and ACV; with features of full
functions, high accuracy, stable performance, easy and reliable operation, it
is available to test RCD, insulation and earth of electric equipments. UT525/
UT526 is the ideal selection for repairing, maintaining and testing RCD of all
electric equipments.
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I. Safety Precautions
This instrument was designed, manufactured and tested according to
IEC61010 safety standard (Safety Requirements for Electrical Equipment).
This Instructions describe the warnings and safety rules which ensure the safe
operation and safe state of the instrument, which the user must follow. Please
read following instructions before using.
Warning
● Please read and understood the Instructions before using.
● Please follow the requirements of the Instructions, keep the
Instructions well for further reference at any time.
● During testing, incorrect operation will cause accident and
instrument damage.
Sign on the instrument tell the user that some operations should be
made according to relative requirements of the Instructions to ensure safety
operation of the instrument.
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UT525/526 Operating Manual
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It means under some conditions, the operation may cause
serious or fatal damages may be caused.
Warning It means taking care to keep away from electric shock.
It means avoiding instrument damage and gain accurate
testing.
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UT525/526 Operating Manual
Note
Danger
Danger
● Do not test circuit with AC440V/DC440V or above.
● Do not test in the place with inammable conditions.
● Do not operate the instrument if the surface of the instrument is wet or the
hand is wet.
● During testing, do not touch the conductive part of the testing pen.
● Do not open the battery cover during testing.
● During testing insulation and RCD, do not touch the circuit to be tested.
Warning
● When there is anything unusual to the instrument, such as the instrument
is damaged or the metal is exposed, please do not use it.
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● Operate carefully under the voltage over 33Vrms, 46.7Vacrms or 70Vdc,
electric shock may be caused under such kind of voltage during operating.
● After completing high resistance testing, the charge storage of the circuit
to be tested must be released.
● Do not replace battery if the instrument is in place with humidity.
● Make sure the all testing wires are connected with the testing ports rmly.
● Before opening cover of the battery, please make sure the instrument is
turned off.
Note
● Before testing resistance, the circuit to be tested must be discharged
completely and separated from the power circuit absolutely.
● If the testing pen or adapter is damaged and needs to be replaced,
please replace with testing pen or adapter with the same model and
electric specications.
● When the battery sign ( ) shows that the battery is used up, please do
not use the instrument any more. If the instrument won’t be used for a long
time, please take out the battery and then keep the instrument well.
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UT525/526 Operating Manual
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UT525/526 Operating Manual
● Do not put or use the instrument in the place with high temperature, high
humidity, inammable or explosive matters and high electromagnetic eld.
● Do not clean the cover of the instrument with wet cloth of detergent, do not
use abrasives or solvent.
● When the instrument is wet, please make it dry and then put it in the
proper place.
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UT525/526 Operating Manual
II. Features
Danger of electric shock may happen
The instrument has double-insulation or reinforced insulation
DC
AC
Earth
● Designed and manufactured strictly according to IEC61010 safety
standard, the instrument meets with Over Voltage Standard (CATIII600V)
and safety standard of Class II Pollution.
● Auto discharge function.
● Red warning light.
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UT525/526 Operating Manual
III. Specications
Error limit: ±(a% reading + digits), one year of warranty period
Environment temperature: 23±5℃
Environment humidity: 45-75%RH
UT525/UT526 RCD testing indexes
RCD testing current 10mA 30mA 100mA 300mA
Applied voltage Voltage: 220V±10%, frequency: 45Hz-65Hz
Accuracy tolerance
RCD testing current accuracy tolerance with AC (220V±2): (0+10%)
Testing time
range when
switch of
RCD is off
Accuracy tolerance ±(5%+2)
(10mA) range: 0-2,000mS
(30mA) range: 0-500mS
(100mA) range: 0-300mS
(300mA) range: 0-300mS
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UT525/526 Operating Manual
UT525 earth testing indexes
Rated voltage About 5.0V
Test range 0.01Ω-200Ω
Test current >200mA for 0.00Ω-2.00Ω
Accuracy tolerance 0.01Ω-200Ω: ±(2%+5)
UT526 earth testing indexes
Rated voltage About 5.0V
Test range 0.01Ω-2,000Ω
Test current >200mA within 0.00Ω-2.00Ω
Accuracy tolerance 0.01Ω-2,000Ω: ±(2%+5)