Battery master switch

Battery main switches for boats, yachts and vehicles

The battery main switch isolates the battery system from the on-board network. It prevents deep discharge during lay-up, makes maintenance safe and allows quick emergency shutdown. philippi offers rotary and selector switches, flange switches for high currents and remote-controlled switches for 12, 24 and, depending on the model, 48 V.

In short: the main switch switches, the main fuse protects. Both belong together; the fuse sits no more than 17.8 cm from the positive terminal (ABYC E-11).

The types

• BHM and BHS rotary switches: round, for surface, flush or panel mounting. BHM size 300 A continuous (900 A for 30 s), BHS size 350 A (1,200 A for 30 s), also double-pole.
• BWS selector switches: switch between two batteries or connect them.
• BH-F flange switches: for high currents from 200 A rated current, IP 67, also double-pole.
• Remote-controlled FHR, FBR and XD series switches: operated via push button, P-BUS or NMEA 2000; they can sit right at the battery while the control point is freely chosen.

The Blue Sea switch ratings apply to 120 mm² cable and are continuous ratings in the on state, not switching ratings. All data at a glance: Blue Sea battery main switches.

Choosing the right switch

Frequently asked questions

Do I also need a main fuse? Yes. The switch isolates but does not protect against short circuits. The main fuse sits no more than 17.8 cm from the positive terminal; with lithium batteries only as an SHB bolt-down fuse or Class T.

May I switch under load? That depends on the switch. The current ratings of the rotary switches are continuous ratings in the on state, not switching ratings. Switch off large consumers before switching over.

Which current rating do I need? The continuous rating of the switch must exceed the highest current in the main cable, i.e. what all consumers draw together. Inrush currents of winches and starters are covered by the short-time rating.

Are there remote-controlled main switches? Yes, the FHR, FBR and XD series switches are operated electrically, for example via push button, the P-BUS system or NMEA 2000.