LifeBasis CD-7920 Digital Ultrasonic Cleaner

Introduction to Ultrasonic Cleaning

Ultrasonic cleaning utilizes high-frequency vibrations to generate millions of tiny air bubbles within the cleaning liquid. When these bubbles burst, they create a powerful cavitation effect that dislodges debris from the surfaces of items, achieving a thorough clean.

In most cases, regular tap water is sufficient for ultrasonic cleaning. Purified or distilled water yields the same cleaning results. However, for items with significant oxidation, such as silver or copper, special cleaning solutions may be required to remove the tarnish.

Important: Always read the user manual carefully before operating the device and observe all warnings and instructions.

Safety Precautions

General Safety

• Keep the device away from children. It is not intended for use by individuals with reduced physical, sensory, or mental capabilities, or those lacking experience, unless supervised or trained.
• Keep packaging materials away from children to prevent suffocation hazards.

Electrical Safety

• Never use the device while bathing or in proximity to water.
• Do not immerse the device or power cord in water or other liquids.
• Avoid touching the power plug with wet hands.
• If the unit falls into water during operation, immediately remove the power plug from the socket before touching the unit.
• Do not spray water or liquids directly onto the device.
• Never operate the device unattended.
• Only use manufacturer-approved components.
• When unplugging, grasp the power plug, not the cord.
• Protect the power cord from damage; do not let it get caught or dragged across hot surfaces.
• Do not use the device if the power plug, cord, housing, or any other part is damaged.
• Do not disassemble the unit; service should only be performed by qualified professionals.
• If the unit is damaged, malfunctioning, or has been submerged, contact a qualified service provider.
• Remove the power plug from the socket in case of malfunction, before cleaning, if the device will not be used for an extended period, and after each use (recommended).
• For added protection against electrical shock, installation of an earth leakage circuit breaker with a rated tripping current of no more than 30 mA is recommended. This should be performed by a qualified electrician.
• Some units may feature a polarized plug (one blade wider than the other) for safety. This plug will only fit into a polarized outlet one way. If it does not fit, reverse the plug. If it still does not fit, contact a qualified electrician.

Fire Hazards

• Never block the device's vents. Keep them clear of lint, hair, and other materials.
• Do not place the device on soft surfaces like beds or couches where vents can be blocked.

Other Precautions

• Do not operate the product without water in the tank, as this can damage the unit.
• Do not plug in the power cord before adding water. Do not fill the tank above the 'MAX' line to prevent overspill.
• Do not use solutions containing abrasive substances or strong corrosive chemicals not recommended by the manufacturer.
• Place the device on a dry, flat surface for operation.
• Severe electromagnetic interference may cause the device to malfunction. If this occurs, unplug and reinsert the power cord to restart.

Items Not Suitable for Ultrasonic Cleaning

• Soft Jewelry: Pearls, emeralds, ivory, coral, agate, sea turtle shells, etc.
• Welded, Plated, and Glued Items: Items with welded joints, plating, or glued components.
• Watches: Except for diver's watches with a depth rating over 50m (150ft).
• Others: Wood, coated glass, ceramics, camera filters with pre-existing cracks.

These items may be scratched or damaged due to the cleaning process. Ultrasonic cleaning can enlarge gaps in welded or glued items, potentially causing separation. Water may penetrate non-waterproof watches. Use the provided watch stand if unsure.

Wave Patterns and Cleaning Effectiveness

The CD-7920 utilizes professional-grade full-wave circuitry, offering superior cleaning performance compared to half-wave circuitry found in other models. The CD-7920S features separately excited circuitry.

Wave Pattern Comparison:

• Full-wave circuitry (CD-7920): Generates a more consistent and powerful cleaning wave pattern.
• Separately excited circuitry (CD-7920S): Offers effective cleaning.
• Half-wave circuitry (other personal models): Provides less effective cleaning.

Cleaning Effect Comparison:

• Very effective (80%): Achieved with full-wave circuitry.
• Effective (65%): Achieved with separately excited circuitry.
• Less effective (25%): Achieved with half-wave circuitry.

Caution: Never turn on the unit when the tank is empty. Doing so can cause the ultrasonic energy to concentrate, leading to overheating and potential damage to the PCB.

Unit Components

The ultrasonic cleaner consists of the following parts:

1. On/Off Button
2. Time Display
3. SET Button
4. View Window (Lid)
5. Blue LED Indicator
6. Stainless Steel Tank
7. Housing
8. Power Cord

Optional Accessories:

• CD Stand
• Watch Stand
• Plastic Basket

Applications and Timer Settings

The digital timer offers five settings for various cleaning needs:

• 180 seconds (3 Minutes): Default time for normal cleaning.
• 300 seconds (5 Minutes): Recommended for cleaning several items together.
• 480 seconds (8 Minutes): Recommended for greasy items and multiple items.
• 090 seconds (1.5 Minutes): Suitable for CD/DVD and eyeglasses cleaning.
• 600 seconds (10 Minutes): Recommended for heavily soiled items and multiple items.

Suitable Items for Cleaning:

• Jewelry: Gold, silver, solid metal jewelry (necklaces, rings, earrings, bracelets).
• Watches: Watch bands, waterproof wristwatches.
• Toiletry Items: Electric toothbrush heads, electric shaver heads, razors, dentures, combs.
• CDs and Eyeglasses: CDs, DVDs, eyeglasses, sunglasses.
• Office Equipment: Printer heads, fountain pens, rubber stamps.
• Metal Items: Silverware, bearings, gears, valves, nozzles, small metal parts, coins, metal badges.

Note: Prolonged cleaning times may cause small parts like screws on eyeglasses to loosen.

Operation Instructions

1. Open the cover. Place the items to be cleaned inside the basket, then place the basket inside the stainless steel tank.
2. Fill the tank with tap water. Ensure the water covers the items but does not exceed the 'MAX' line.
3. Close the cover and plug in the power cord. The display will show '180' seconds, the default cleaning time.
4. Select the desired cleaning time by pressing the 'SET' button. The timer cycles through 180s, 300s, 480s, 90s, and 600s.
5. Press the 'ON/OFF' button to start the cleaning process. The blue LED light will illuminate, and the timer will count down. A buzzing sound during operation is normal.
6. When the timer reaches '000', the cleaning process stops automatically.
7. To stop the process early, press the 'ON/OFF' button. To repeat a cycle or increase the time, press 'SET' to select the desired time and then 'ON/OFF' to restart.

Important: Continuous operation for extended periods can generate heat and raise the water temperature. Do not use the unit for more than 20 minutes continuously. Allow a 10-minute break between cycles to prolong the unit's lifespan.

Maintenance and Storage

• Unplug the power cord and empty the unit after each use. Do not leave water in the tank for extended periods.
• When plugged in but not operating, the LED light may remain lit, consuming less than 1W of power.
• Pour water out from the sides of the tank, avoiding the control panel area.
• Do not run the unit continuously for over 20 minutes. Allow a 10-minute break between cycles.
• Do not spray water directly onto the housing. Use a soft towel to wipe the tank and housing dry.
• Avoid prolonged exposure to direct sunlight. Store the unit in a dry, cool, and well-ventilated area.

Use of Optional Accessories

• Basket: Use the plastic basket for cleaning small or delicate items. Ensure delicate items do not touch each other if cleaning multiple pieces. Note that the plastic basket absorbs approximately 30% of ultrasonic energy, which may reduce cleaning effectiveness.
• Watch Stand: Use the watch stand to keep the watch body elevated above the water level while cleaning the watch band. This is important for watches with a depth rating less than 50m (150ft) to prevent water ingress.
• CD Stand: The CD stand is designed to hold CDs or DVDs for cleaning. Up to two CDs/DVDs can be cleaned simultaneously.

Common Cleaning Methods

• Regular Cleaning: Use tap water only. Place items in the basket, put the basket in the tank, fill with water between MIN and MAX lines, and start the unit. Dirt will appear as 'smoke' in the water, indicating the cleaning process.
• Enhanced Cleaning: Add appropriate cleaning solutions to the water (e.g., one part solution to ten parts water) to boost cleaning power. After cleaning, run the unit with plain water for an additional 90 seconds to rinse off any residual solution.
• Partial Cleaning: For longer items that do not fit entirely in the tank, clean one end first, then turn the item around to clean the other end. Place sharp items in the basket to prevent scratching the tank.

Specifications

Performance Test (Foil Test)

An ultrasonic cleaner's effectiveness can be gauged by its ability to pierce foil paper placed at the bottom of the tank. A larger hole indicates stronger cleaning ability.

Test Procedure:

1. Place a piece of foil paper at the bottom of the water tank and fill with sufficient water.
2. Turn on the device for 90 seconds.

Observe the foil paper after the test. The image shows a comparison of an untested foil piece (left) and a foil piece after the 90-second test, showing significant perforations (right).