BEP Battery Selector Switch PRO 771 12/24V 400A - Professional Battery Management with Protection

The BEP PRO INSTALLER battery selector switch type 771 with alternator protection offers professional switching between two batteries. With its 3-pole design, 2 x 10 mm terminals and integrated alternator protection, it is ideal for demanding marine applications.

Product features

• 3-pole with alternator protection - Protects the alternator during switching.
• 2x 10mm connectors - (3/8") for secure wiring
• 400A current rating - Suitable for demanding vehicle electrical systems
• STD assembly - Standard assembly for surface mounting and panel installation/assembly
• 12/24V voltage - Universally applicable (max 48V)
• Switch positions - 1 / 2 / 1+2 / Off for flexible battery management
• Compact design - 98 x 98 mm base area, 92 mm height
• BEP Quality - Premium manufacturer of marine electrical systems

Available versions

Alternator protection

Integrated protection: Prevents damage to the alternator when switching under load.

Make-Before-Break: Ensures that the new connection is made before the old one is broken.

Safe switching: Switching can be done safely even with the engine running.

3-pole version

2x 10mm connectors: Generous connectors (3/8") for secure cabling.

400A current rating: Suitable for demanding electrical systems and high loads.

12/24V voltage: Universally applicable, max. 48V.

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.

STD assembly

Surface mounting: For flexible placement in the engine compartment or other locations.

Panel installation and assembly: Versatile mounting options for professional installation.

Compact design: 98 x 98 mm base area, 92 mm height.

Application areas

• Sailing yachts and motorboats with dual battery system
• Professional battery management for starter and auxiliary batteries
• Motorhomes and camping with two batteries
• Commercial vehicles with dual battery system
• All applications with 12V or 24V on-board voltage
• Installations requiring alternator protection
• Shipyards and service companies

Advantages at a glance

Alternator protection: Prevents damage during switching under load.

3-pin: Professional battery management with two batteries.

Flexible: 4 switching positions for optimal battery management.

Heavy-duty: 400A for demanding applications.

Professional: BEP PRO INSTALLER quality.

💡 Tip

The integrated alternator protection is especially important if you frequently need to switch between positions while the engine is running. Use position 1 for normal operation with the starter battery. Keep battery 2 (auxiliary battery) as a reserve. Use positions 1 and 2 in an emergency if the starter battery is too weak, or to charge both batteries while driving. Switch to the "Off" position during extended periods of inactivity to prevent parasitic drain. Clearly label the switch positions. Install the switch in an easily accessible location. Combine with BEP PRO INSTALLER busbars and fuse holders.

⚠️ Important

When installing, ensure correct polarity and use adequately sized cables (rated for at least 400A). The switch should be installed as close to the batteries as possible. Tighten the connections securely to avoid contact resistance. Although alternator protection is integrated, exercise caution when switching under load. Ensure all high-current consumers are switched off before switching. Use positions 1 and 2 only when necessary. Regularly check the switch's function and condition. Observe the maximum voltage of 48V.

Ideal for

• Boat owners with dual battery system
• Sailors with high energy requirements
• Professional installations with the BEP PRO INSTALLER system
• Applications requiring alternator protection
• Motorhome drivers with starter and service batteries
• Workshops and service centers

Scope of delivery

You will receive a BEP battery selector switch PRO 771 12/24V 400A 3-pole with alternator protection and STD mounting (BP771-SFD) in a self-service pack - ready for installation in your vehicle electrical system.

BEP PRO INSTALLER Quality

The BEP PRO 771 battery selector switch combines the highest quality with professional functionality and integrated alternator protection - for reliable and safe battery management in marine electrical systems.