UNI-T UT321, UT322, UT323, UT325 Operating Manual

Table of Contents

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Title Page

Safety Information
Getting Started
Components
Display Elements
Buttons
Using the Thermometer
Changing Setup Options
Entering and Exiting Setup
Changing the Logging Interval
Changing the Thermocouple Type
Changing the Offset (T1)
Changing the Offset (T2)
Sleep Mode
Changing the Line Frequency
Setting the Time
Setting the Low Limit Alarm (Lo)
Setting the High Limit Alarm (Hi)

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Title Page

Measuring Temperatures
Connecting a Thermocouple
Displaying Temperatures
Holding the Displayed Temperatures
Turning on and off of display backlight
Viewing the MIN, MAX, and AVG Readings
Using the Offset to Adjust Probe Errors
Over Limit Alarm
Over Limit Signal Output
Debug
Using Memory
Starting and Stopping Logging
Viewing Logged Readings
Clearing Memory
Communicating with a PC

Enabling or Disabling Over Limit Signal Output
Enabling or Disabling Normal Temperature Compensation (NTC)
Enabling or Disabling Debug

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Maintenance
Replacing the Battery
Cleaning the Case
Specifications
Environmental
General
Electrical

Title Page

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Safety Information

The Uni-Trend Model UT321, UT322, UT323 and UT325 Thermometers (‘the
thermometer) are microprocessor-based, digital thermometers designed to use
external J-, K-, T-, E-, R-, S- and N- type thermocouples (temperature probes) as
temperature sensors.

UT321: T1, suitable for K-, J-, T- and E- type thermocouples
UT322: T1 and T2, suitable for K-, J-, T- and E- type thermocouples
UT323: T1, suitable for K-, J-, T-, E-, R-, S- and N- type thermocouples. Equipped
with over limit alarm, over limit signal output and user self-debug features.
UT325: T1 and T2, suitable for K-, J-, T-, E-, R-, S- and N- type thermocouples.
Equipped with over limit alarm, over limit signal output and user self-debug features.

Use the thermometer only as specified in this manual. Otherwise, the protection
provided by the meter may be impaired.

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Refer to safety information in Table 1 and the international symbols in Table 2.

Table 1. Safety Information

Before using the thermometer inspect the case. Do not use the thermometer if it
appears damaged. Look for cracks or missing plastic. Pay particular attention to the
insulation around the connectors.
Disconnect the thermocouple(s) from the thermometer before opening the case.
Replace the batteries as soon as the battery indicator ( ) appears. The possibility
of false readings can lead to personal injury.
Do not use the thermometer if it operates abnormally. Protection may be impaired.
When in doubt, have the thermometer serviced.
Do not operate the thermometer around explosive gas, vapor, or dust.
Do not apply more than the rated voltage, as marked on the thermometer (30V|),
between the thermocouple(s), or between any thermocouple and earth ground.
When potential differences are anticipated between the thermocouples, use electrically
insulated thermocouples.
When servicing the thermometer, use only specified replacement parts.
Do not use the thermometer with any part of the case or cover removed.

Warning

A warning identified conditions and actions that pose hazards to the user. To avoid
electrical shock or personal injury, follow these guidelines:

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Caution

A caution identifies conditions and actions that may damage the meter or the
equipment under test.

Use the proper thermocouples, function, and the range of your thermometer.
When carrying two thermocouples measurement, make sure there are no
potential differences between two thermocouples.
Do not attempt to recharge the battery.
Match the + and – polarities of the battery with the battery case.

Table 2. International Symbols
Refer to the manual for information about this feature
Complies with European Union directives
Battery

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Getting Started

Everything in this Users Manual applies to all Models of UT321, UT322, UT323 and
UT325 unless otherwise indicated.

To become familiar with the thermometer, study the following:

Figure 1 and Table 3 describe the components
Figure 2 and Table 4 describe the display.
Figure 3-a and 3-b and Table 5 describes the functions of the buttons.

Then read the following sections.

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Figure 1. Components

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Table 3. Components

Display
Buttons
Thermocouple T1 input
Thermocouple T2 input (UT323 and UT325 only)
USB Port
SIGN Port - Over Limit Signal Output (UT323 and UT325 only)
NTC
Battery Door
9V battery (6F22 )

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Table 4. Display Elements

Setup is in progress when the icon blinks
Display readings of maximum, minimum and average
Data Transferring is in progress
Logged readings are displayed when the icon blinks
Low battery. Replace the battery
The thermocouple type
The temperature units
Secondary Display 1
Under Calibration mode when the icon blinks. The displayed reading is fixed.
Secondary Display 2
The thermocouple measurement includes an offset. See “Changing Setup

Options”
Readings are being logged when the icon blinks
Primary Display
The displayed readings do not change
The symbol of display backlight

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Figure 3-a UT321 and UT323 buttons set

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