BEP Battery Selector Switch 721 Heavy Duty 12/24V 350A - Robust Battery Management

The BEP Type 721 Heavy Duty battery selector switch offers robust and reliable battery management for the most demanding marine applications. Featuring tinned copper studs (12 mm / 1/2"), fiber-reinforced plastics, and extreme durability, it is ideal for professional, high-performance electrical systems.

Product features

• Heavy Duty version - Robust construction for maximum loads
• 12mm copper bolts - tinned (1/2") for optimal conductivity
• 600A continuous - continuous load for the most demanding vehicle electrical systems
• 800A peak load - 5 minutes peak load
• 2500A motor start - 10 seconds for starting currents
• Stainless steel components - washers and nuts made of stainless steel
• Fiber-reinforced plastics - High temperature resistant and robust
• 3 removable side panels - To protect the connections

Available versions

Heavy-duty construction

Extreme load capacity: 600A continuous, 800A for 5 minutes, 2500A for 10 seconds motor start.

12mm copper bolts: Tin-plated (1/2") for optimal electrical conductivity and corrosion protection.

Robust construction: Fiber-reinforced plastics for the highest temperatures and loads.

Tinned copper bolts

12mm diameter: Generous bolts (1/2") for very large cable cross-sections.

Tinned copper: Optimal conductivity and corrosion protection for marine environments.

Stainless steel fastening: Washers and nuts made of corrosion-resistant stainless steel.

Switch positions

Position 1: Only battery 1 active - battery 2 as reserve.

Position 2: Only battery 2 active - battery 1 as reserve.

Position 1+2: Both batteries connected - for starting the engine with a weak battery or for parallel charging.

Position Off: All batteries disconnected - for storage and safety.

protective plates

3 removable side plates: Protect the connections from contact and mechanical damage.

Safety: Prevents accidental short circuits.

Flexible: Removable for easy installation and maintenance.

Application areas

• High-performance yachts with large battery banks
• Professional shipping
• Heavy motorboats with high starting currents
• Inverter installations with extreme current levels
• All applications with 12V or 24V and the highest requirements
• Shipyards and service companies
• Heavy Duty New Installations

Advantages at a glance

Heavy Duty: Extreme load capacity up to 2500A for motor starting.

12mm bolts: Tinned copper for optimal conductivity.

Robust: Fiber-reinforced plastics and stainless steel components.

Flexible: 4 switching positions for optimal battery management.

Protected: 3 removable side panels for protection.

💡 Tip

This heavy-duty switch is specifically designed for very high currents. Use appropriately large cable cross-sections (the 12mm bolts allow for very large cross-sections). Use position 1 for normal operation. Keep battery 2 as a backup. Use positions 1 and 2 only in emergencies or for parallel charging. The removable side plates should be installed after installation to protect the terminals. Ensure adequate ventilation at high currents. Combine with BEP heavy-duty busbars and fuse holders for a professional system.

⚠️ Important

During installation, ensure correct polarity and use adequately sized cables for the extreme currents (600A continuous requires very large cross-sections). The switch should be installed as close to the batteries as possible. Tighten the connections securely to avoid contact resistance. Never switch the switch while the engine is running – this can damage the alternator. Use positions 1 and 2 only when necessary. Install the protective plates after installation. Regularly check the function and condition of the switch. Heat may be generated at high currents – ensure adequate ventilation.

Ideal for

• High-performance yachts with extreme requirements
• Professional shipping
• Heavy diesel engines with high starting currents
• Inverter installations with very high currents
• Workshops and service centers
• Anyone who needs maximum durability and reliability

Scope of delivery

You will receive a BEP battery selector switch 721 Heavy Duty 12/24V 350A 3-pole (BP721) in a SB pack - including 3 removable side plates, stainless steel washers and nuts.

BEP Heavy Duty Quality

The BEP 721 Heavy Duty battery selector switch combines the highest quality with extreme durability - for reliable battery management even under the toughest conditions in marine electrical systems.