Unit UT528 User manual

P/N:110401105431X
REV.3
DATE:2015/07/15

Overview - UT528/528AU
UT528/528AU from.
UT528/528AU Main Unit
UT528/528AU

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＊EarthNullingBlock 1x
＊Neck strap 1x
＊IEC Lead 1 x
＊Batteries C Type R14 1.5V UM2 6 x
Safety Information
Warnings - Please be aware of the following warnings.
●Before using the unit and test leads inspect both items. Do not use the unit
and test leads if they are damaged or the case is broken or damaged as this
could result in electrical shock.
●Replace the battery as soon as the battery indicator “ ”appears. Low
battery levels may produce inaccurate readings.
●Do not use or store the unit in high temperature, humid, flammable or
electromagnetic environments as damage and incorrect readings may result.
●If the tester requires repair or replacement please contact your local service
center.
Declaration of Conformity
Uni-T manufactures this product and declares that this product conforms to the

UT528/528AU

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8.Warning Symbol
9.Unit Error
10.Readings and Cable Results
11.Leakage Current
12.Double Insulated / Class II Test
13.Class I Test

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ClassITestButton+Zero/NullSelection
Class II Test Button + 250V Insulation Selection
IEC / Cable Test Button +30m Long Lead Selection
Earth Probe Mains / IEC testing

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Front Panel Operation
1: Press +button to Power on / Power Off.
2: Press button when testing a CLASS I Appliance.
3: Press button when testing a CLASS II Appliance.
4: Press button when performing Cord / Extension Lead testing.
Advance Features
5: Press and hold the button this will set the tester into Long Lead Mode.
6. Press and hold the button to activate 250v insulation test.
You can exit the above advanced features by turning the unit off and back on.

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Before Testing - Zero the Earth Bond Test Lead!
Plug the earth probe into the rear of the unit and connect it to the earth nulling
adapter. Plug the earth nulling adapter into the front panel earth socket to
complete the circuit.
Press and hold the button for 5 seconds to zero the earth bond reading
using the earth bond lead and the nulling adapter together in the front test socket.
This will null the earth reading of the test lead and “GOOD” will be displayed once
complete. It is good practice to do this once prior to carrying out testing.
Auto Switch Off
The unit will automatically switch off after approximately 2 minutes if no buttons
are pressed.
Testing a Class 1 Appliance
Plug the appliance into the UT528/528AU panel main socket. Plug the earth test lead into
the socket on the UT528/528AU end panel. Connect the earth crocodile clip to an

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exposed metal part on the appliance as shown in Diagram 3.
1. Earth / Protective Conductor Test
Press the Class 1 test button to start the test. The earth resistance test will
begin.

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If the earth resistance measured is greater than 0.2Ω, the meter will display “×
Rpe”, which is a FAIL. If this occurs, re- check the connections between the pin of
the plug to the bodywork of the appliance and that the crocodile clip is attached to
clean earthed metalwork on the appliance (try attaching the clip to an alternative
piece of metalwork). If all connections are ok the appliance earth connection may
be faulty.
The PASS mark for the earth bond test is 0.2 Ωfor a Class 1 appliance.
If the reading is less than 0.2 Ω, the meter will display “√Rpe”, which is a PASS.
The unit will then automatically attempt to proceed to the insulation test. If it
detects that the appliance’s power switch is in the ON position it will carry out the
insulation test automatically.
If this is not detected the unit will display a flashing symbol and also “LO
LOAD”. Press the button to proceed to the insulation test.