1. Introduction
The CREST CR4 is a versatile dive computer designed to meet the needs of various diving activities, including Scuba Diving, Free Diving, and acting as an instrumentation Gauge. It offers advanced features for both recreational and technical divers, ensuring safety and providing essential dive data.
2. Setup
2.1. Charging the Device
The CREST CR4 features a rechargeable lithium-ion battery. Before initial use, ensure the device is fully charged. The watch supports fast charging, reaching up to 85% charge in approximately 1 hour.
To charge:
- Connect the charging clip to the back of the CREST CR4, ensuring the pins align with the charging contacts.
- Connect the USB end of the charging cable to a power source (e.g., USB wall adapter, computer USB port).
- The watch display will indicate charging status.
2.2. Initial Power-Up and Wearing
After charging, the device can be powered on. The watch is designed to be worn on the wrist using its 22mm anti-allergic silicone strap. The strap can be replaced with compatible third-party watch straps if desired.
3. Operating the CREST CR4
The CREST CR4 features multiple buttons for navigation and mode selection: POWER, UP, MODE, and DOWN. The interface is designed for clear readability, even underwater, and includes a backlight that activates when the watch is held up.
3.1. Dive Modes
The CR4 supports the following dive modes:
- Scuba Mode: Functions as a standard dive computer, calculating No-Decompression Limit (NDL) and indicating required decompression stops.
- Gauge Mode: Tracks depth and dive time without calculating NDL or decompression stops.
- Apnea Mode: Dedicated free-diving mode for tracking free dives.
3.2. Navigation and Settings
Use the UP and DOWN buttons to scroll through menu options. The MODE button typically selects an option or enters a submenu, while the POWER button often acts as a back or exit function.
Key settings include:
- Date Format: Adjust how the date is displayed.
- Time: Set the current time.
- Safety Factor: Configure the decompression algorithm to Conservative, Normal, or Aggressive based on your preference and dive plan.
- Nitrox Settings: For Nitrox diving, set the oxygen percentage (21% to 56%).
3.3. Dive Log
The CR4 stores over 200 dive logs. You can access these logs to review past dive data, including dive time, maximum depth, temperature, and more. Dive logs and residual nitrogen can be reset as needed.
4. Maintenance
4.1. General Care
- Rinse the dive computer with fresh water after every dive to remove salt, sand, and other debris.
- Dry the device thoroughly with a soft cloth before storing.
- Avoid exposing the device to extreme temperatures or direct sunlight for prolonged periods.
- The bezel and buttons are made of 316 stainless steel, and the lens is K1 tempered glass, offering good resistance to wear and corrosion.
4.2. Battery Care
- Charge the battery regularly, even if not diving frequently, to maintain battery health.
- The battery has a life of approximately 25 dives with the backlight on, or up to 3 months in standby mode.
- Avoid completely draining the battery for extended periods.
5. Troubleshooting
If you encounter issues with your CREST CR4, consider the following:
- Device not turning on: Ensure the battery is sufficiently charged. Connect to the charger and check for charging indication.
- Display issues: If the display is dim or unresponsive, try recharging the device. If the issue persists, contact customer support.
- Inaccurate readings: Ensure the device is properly calibrated and settings (e.g., Nitrox percentage, safety factor) are correctly configured for your dive.
- Buttons unresponsive: Ensure no debris is lodged around the buttons. Rinse thoroughly with fresh water.
- Data synchronization issues: Check the connection to your computer or mobile device. Ensure any required software or apps are up to date.
For persistent problems, refer to the official CREST support resources.
6. Specifications
| Feature | Specification |
|---|---|
| Operating Depth Limit | 100 meters / 330 feet |
| Multiple Modes | Scuba, Gauge, Apnea Mode |
| Air and Nitrox | Oxygen 21%~56% |
| Algorithm | Buehlmann ZH-L16C |
| Safety Factor | Conservative, Normal, Aggressive |
| Battery Type | Rechargeable Lithium-ion Battery |
| Battery Life (Dive Mode) | 25 dives with backlight on |
| Battery Life (Standby Mode) | Up to 3 months |
| Dive Log Storage | 200+ |
| Screen Resolution | 110 x 110 PIXEL |
| Display Size | 2.9 cm / 1.14 inches |
| Weight | 95g ± 5g |
| Bezel and Button | 316 Stainless Steel |
| Lens | K1 Tempered Glass |
| Straps | 22MM Anti-allergic Silicone |
| Temperature Displayed | 0°C ~ 40°C (32°F ~ 104°F) |
| Operating Temperature | -5°C ~ 40°C (23°F ~ 104°F) |
7. User Tips
Based on general user experiences with dive computers:
- Always perform a pre-dive check of your computer's battery level and settings.
- Familiarize yourself with the menu navigation on land before your dive.
- Consider setting the safety factor to 'Conservative' for added safety, especially when diving in unfamiliar conditions or after a long break.
- Regularly sync your dive logs to a computer or mobile device to keep a record of your dives and free up device memory.
Note: No specific user reviews or Q&A were provided for product-specific tips.
8. Warranty and Support
For warranty information, technical support, or service inquiries, please refer to the official CREST website or contact your authorized dealer. Keep your proof of purchase for warranty claims.
