Bigblue B406 User Manual

The Bigblue B406 is a professional-grade underwater dive light featuring a maximum output of 2000 lumens, multiple lighting modes (High, Medium, Low, SOS, Strobe), rechargeable lithium-ion battery with USB-C charging, durable aluminum alloy construction, IPX8 waterproof rating up to 100 meters, adjustable beam focus, and a wrist lanyard for secure handling. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

Features at a Glance

Key components: Aluminum alloy body, CREE XHP70.2 LED, USB-C charging port, magnetic rotary switch, adjustable focus bezel, wrist lanyard.

Feature	Description
Maximum Output	2000 lumens on High mode
Lighting Modes	High, Medium, Low, SOS, Strobe
Battery	Rechargeable 5000mAh lithium-ion
Charging	USB-C fast charging (5V/2A)
Waterproof Rating	IPX8 (up to 100 meters/328 feet)
Beam Distance	Up to 200 meters on High
Body Material	Aerospace-grade aluminum alloy
Switch Type	Magnetic rotary switch
Focus	Adjustable from spot to flood
Runtime	Up to 12 hours on Low mode

Installation

Unpack and inspect contents. Ensure all components are present.

1. Attach wrist lanyard: Thread through lanyard hole and secure with knot.
2. Charge battery: Connect USB-C cable to light and power source.
3. Install optional accessories: Mount to camera bracket if needed.
4. Check O-rings: Ensure clean and lubricated before diving.

WARNING! Do not use if housing is damaged. Always check waterproof seals before submersion.

First-Time Setup

Fully charge before first use.

1. Charge: Connect USB-C cable; red indicator shows charging, green when full.
2. Power on: Rotate magnetic switch clockwise until click.
3. Select mode: Single click to cycle through High, Medium, Low, SOS, Strobe.
4. Adjust focus: Rotate bezel to change beam pattern.
5. Test waterproofing: Submerge in shallow water for 30 minutes before deep dive.

CAUTION! Never open housing underwater. Ensure switch is in OFF position during charging.

Specifications

• LED: CREE XHP70.2
• Output: 2000 lumens (High), 1000 lumens (Medium), 300 lumens (Low)
• Battery: 5000mAh lithium-ion, 3.7V
• Charging Time: 4 hours (0-100%)
• Runtime: 2 hours (High), 5 hours (Medium), 12 hours (Low)
• Waterproof: IPX8, 100 meters
• Dimensions: 150mm length × 45mm diameter
• Weight: 280g (without battery)
• Operating Temp: -20°C to 40°C (-4°F to 104°F)
• Storage Temp: -20°C to 60°C (-4°F to 140°F)

Controls and Settings

Magnetic Rotary Switch: Rotate to turn ON/OFF. Single click when ON to cycle modes.

Mode Sequence: High → Medium → Low → SOS → Strobe → High

Focus Adjustment: Rotate front bezel clockwise for spot beam, counterclockwise for flood beam.

Battery Indicator: LED near switch shows battery status (Green: >70%, Yellow: 30-70%, Red: <30%, Flashing Red: Charge immediately).

Lock Mode: Press and hold switch for 3 seconds to lock/unlock (prevents accidental activation).

Connecting Devices

USB-C Charging: Use included cable to connect to USB power adapter or computer.

1. Ensure light is OFF and dry before charging.
2. Open charging port cover; insert USB-C cable fully.
3. Connect to 5V/2A power source (not included).
4. Close cover securely after charging.

Camera Mounting: Use 1/4"-20 tripod socket on bottom of light.

Tip: Use only included or certified USB-C cable. Do not use damaged cables.

Charging & Battery Care

Supports USB-C fast charging.

1. Charging: Connect to power; red LED indicates charging, green when full.
2. First Charge: Charge fully for 4 hours before first use.
3. Regular Use: Recharge when battery indicator shows red.
4. Storage: Charge to 50-60% if storing for more than 3 months.
5. Battery Replacement: Contact manufacturer for battery replacement service.

WARNING! Do not charge underwater. Do not expose battery to extreme temperatures. Use only specified charger.

Maintenance & Storage

Rinse with fresh water after saltwater use. Lubricate O-rings every 6 months.

1. Cleaning: Rinse exterior with fresh water; dry completely.
2. O-ring Maintenance: Clean with soft cloth; apply silicone grease lightly.
3. Lens Cleaning: Use microfiber cloth to clean lens surface.
4. Storage: Store in cool, dry place away from direct sunlight.

CAUTION! Do not use alcohol or solvents on O-rings. Do not disassemble beyond user-serviceable parts.

Safety Information

Do not look directly into LED. Keep away from children. Do not use if housing is cracked.

• Never point at eyes at close range
• Do not modify or disassemble
• Use only original accessories
• Check waterproof seals before each dive
• Do not use in explosive atmospheres

Regulatory Information

CE, RoHS, FCC compliant. Contains lithium-ion battery - follow local regulations for disposal. Copyright © 2025 Bigblue. For support, visit www.bigbluedivelights.com or contact [email protected].

Troubleshooting

Symptom	Possible Cause	Corrective Action
Light won't turn on	Battery depleted	Charge for 4 hours; check charging indicator
Dim output	Low battery	Recharge immediately
Water inside housing	Damaged O-ring	Stop use immediately; contact service center
Switch not responding	Lock mode activated	Press and hold for 3 seconds to unlock
Not charging	Dirty charging port	Clean port with dry cloth; try different cable
Overheating	Extended use on High	Switch to lower mode; allow to cool

Reset: Remove battery for 30 seconds, then reinstall.

Service: [email protected]; www.bigbluedivelights.com/support