Automotive Products

Automotive products list

Battery Master Switches (BMS) - The Big Red Switch

BMS-12L, BMS-K-12L & BMS-24L

tl_files/automotive-products/BMS.jpgBattery Master Switch, models BMS-12L, BMS-K-12L &
BMS-124 are a fully sealed, heavy duty, double pole switch
designed for commercial vehicles They are also suitable for
industrial and marine applications.

The outer case is made from an anti-crack material, it has
great resistance to damage from impact, is impervious to fuel
oils, petroleum etc. and in case of fire has self extinguishing

The Battery Master Switch can be operated manually. It can
also be switched ‘OFF’ electronically by a momentary push
switch (cab mounted , not supplied) which operates a solenoid inside the main switch.

The Battery Master Switch is designed so that the ‘alternator field circuit contacts open prior to the main contacts opening. When the switch is turned off electronically this is aprox. 2-3 miliseconds. When turned off manually, the delay on both models is 100-150 milliseconds.

Main terminals of the Battery Switches are 4 heavy duty studs and the Auxiliary terminals are screws protected by a detachable cover on the front of the switch.  

The BMS-K-12L is specifically designed for dual positive isolation.

Installation Sheet-BMS-12L, BMS-24L

Installation Sheet-BMS-K-12L







Input Voltage


12V (Dual Positive Setup Only)



Working Current

200Amps for 5 Minutes


Maximum Current



IP Rating Class



Complies with Australian Standards

AS/NZS 3947.3:2001

AS 60529:2004

AS 60947.1:2004




Design and specifications may change without notice.