UNI-T UT312 Pocketable Vibrometer

I. Introduction to UT312 Product

The UT-312 vibration meter is a split, portable vibration measurer comprising an acceleration sensor and a digital measurement display circuit. It is primarily used to measure vibration displacement, speed (or intensity), and acceleration of mechanical equipment. The current status (e.g., excellence, notice, or danger) of equipment such as fans, pumps, compressors, and motors can be determined by comparing the measured data against enterprise and machine standards, as well as national metrological verification regulations of JJG 676-2000 for working vibration meters.

This instrument features value locking, low-voltage prompts, and automatic shutdown functions. With advantages like a wide measurement scope, simple operation, and convenient portability, it is widely used for patrol detection of equipment vibration in power, metallurgical, and petrochemical industries, making it an ideal tally instrument.

Working Principle

The working principle involves the following flow: Acceleration sensor, processed through a Wave filter, then passes through Integer I and Adjustment I, followed by AC/DC conversion and A/D conversion before displaying on the LCD. A parallel processing path includes Integer II and Adjustment II.

II. Unpacking Inspection

Please unpack and inspect the following items for any deficiencies or damage. Contact the nearest sales service agent of UNI-T if any issues are found.

• Host: 1 set
• Sensor (with magnetic base): 1 (standard) piece assembled to host
• Signal wire of sensor: 1 (standard) wire assembled to host
• Hanging rope: 1 (standard) wire assembled to host
• 9V battery: 1 section
• Manual: 1 book
• Certificate: 1 sheet

III. Safety Notices

Warning: Please pay attention to possible dangers and conditions that could lead to user injury or damage to the vibration meter.

• Use the vibration meter according to the steps shown in this manual to prevent damage.
• Abide by the following guidelines to avoid instrument damage:
• Before using the vibration meter, check if the shell is ruptured or lacks plastic pieces. Do not use the vibration meter with a damaged shell.
• Please replace the battery as soon as possible if the low battery symbol [low battery symbol] appears, to avoid errors in measurement data.
• Do not continue to use the vibration meter if it operates abnormally. Send it to an authorized repair agent of UNI-T for repair.
• Do not use the vibration meter in wet environments or in the presence of combustible and explosive gases.
• Do not detach the shell of the vibration meter to avoid damage.
• Do not attempt to charge the battery, as this may cause personal injury due to battery explosion. Pay attention to the "+" and "-" poles during battery installation.
• Protect the LCD of the vibration meter to prevent scratches or crushing.

IV. Instrument Structure

The instrument structure consists of the following components:

• 1. Signal wire of sensor
• 2. Sensor
• 3. LCD display
• 4. Three-gear toggle switch
• 5. Shell
• 6. Measurement key

The display shows measurement units: m/s² for Vibration acceleration, mm/s for Vibration speed, and µm for Vibration displacement.

The 6th element shown in Figure 1 is the Measurement key button.

V. Instrument Setup and Operation

1. Battery Installation

Open the battery compartment on the back of the instrument and install a 6F22 type 9V laminated cell. Ensure correct polarity before closing the compartment.

2. Power Inspection

Press the measurement key and observe the display. A battery replacement mark in the left end of the display indicates low battery voltage. No mark signifies normal voltage for measurement. The machine will automatically power off 1 minute after the key is released.

3. Selection of Measurement Mode

Toggle the measurement selection switch on the vibration meter to select the desired measurement mode: acceleration, speed, or displacement. An arrow on the display will point to the selected measurement unit.

4. Measurement

Connect the signal wires from the sensor to the input connector of the sensor. For initial use, absorb the sensor with its magnetic base to a vertical cross-section of the article being measured. Press the measurement key with your thumb to enter the measurement status instantly. The measured value will be maintained after releasing the key. Measurement can be continued by pressing the measurement key again. Data will be maintained for 1 minute after releasing the key, at which point the instrument will power off automatically.

Note: Tighten the clasp when connecting signal wires. Hold the instrument and sensor in your hands after measurement. Do not hoist the sensor by its signal wires, as this can affect the service life of the wires.

VI. Technical Indicators

1. General Specification

• LCD display: 3 1/2-bit display; Maximum display: 1999
• Under-voltage display: Indicates low battery.
• Sensor type: Acceleration sensor
• Power demand: 1 x 6F22 9V carbon or alkali battery
• Service life: Operates for more than 20 hours continuously.
• Outline dimension: 185 mm (Height) * 68 mm (Width) * 0 mm (Depth) (for host)
• Weight: Approximately 300g (including battery)

2. Environment Limitation

• Usage: Indoor use
• Safety standard: GB 4793, 1-2007
• Pollution level: Grade 2
• Operation temperature & humidity: 0℃ to 40℃ (not more than 90% RH)
• Storage temperature & humidity: 0℃ to +40℃ (not more than 80% RH)
• Atmospheric pressure: 75 to 106 KPa

3. Technical Specification

• Accuracy: ± 5% of 1 word (percentage of reading + word quantity); Correction period is 1 year.
• Ambient temperature: 0℃ to 40℃
• Ambient humidity: ≤ 80% RH
• Temperature coefficient: 0.1*(accuracy)/°C

VII. Maintenance

Warning: Do not scratch the LCD of the vibration meter during battery replacement or measurement to avoid damage or affect measurement precision. Do not attempt to charge replaced batteries to avoid personal injury due to explosion.

1. Battery Installation and Replacement

• Be sure to replace the battery in a timely manner when the symbol of [low battery symbol] appears on the meter. The battery replacement method is as follows:
• Removing cell cover: Replace the 6F22 9V battery with the same model. Do not install an improper battery.
• Pay attention to the "+" and "-" polarity during battery installation.
• Install the cell cover after installation.

2. General Maintenance

• Inspect signal wires of the sensor constantly, as instrument display may be affected by damage or poor contact of these wires. Do not pull or drag signal wires forcefully.
• The sensor core is sealed and cannot be detached except for sensor signals.
• Clean the instrument shell with a damp cloth and neutral detergent. Do not use abrasive cleaners or solvents.
• If the vibration meter is damaged, send it to an authorized repair agent or professional repair personnel of UNI-T. Do not attempt to repair it yourself.
• Avoid scratching or contaminating the LCD of the vibration meter during usage to prevent oil stains, water leakage, damage, or performance degradation.
• Remove the battery if the instrument will not be used for an extended period.
• Do not store instruments in wet environments, strong magnetic fields, or under high temperatures.

3. Common Troubleshooting