Blue Sea 9003e 350Amp Battery Switch ON/OFF

Item Number: BLS-09003
Manufacturer: Blue Sea Systems
Model Number: 9003e
Manufacturer Country: United States United States
Last Price Update: 07/08/2019

Blue Sea 9003e 350Amp Battery Switch

We recommend the use of several of these switches, as a stop gap measure, on parallel connected 12 and 24 Volt battery banks (Not rated for 48Volt banks), to enable the strings to be easily separated for equalization.

As always the design should be a single series string, but there are good economic arguments for keeping the already purchased batteries until they are used up. With routine equalization of the strings separately, much of the hard sulfation from the parallel bank design can be reversed.

Switches a single battery string to a single load group

  • Ignition protectedsafe for installation aboard gasoline powered boats
  • Case design allows surface or rear panel mounting
  • Meets American Boat and Yacht Council (ABYC) requirements for battery switches
  • 3/8"-16 tin-plated copper studs for maximum conductivity and corrosion resistance, accepts 3/8" and M10 ring terminals.
  • 7/8" (22.22mm) stud length to accept multiple cable terminals
  • Tactile textures indicate knob position by feel only


           Blue Sea 9003e Battery On / Off Switch     Specifications

Switch Type 

Single Circuit ON-OFF



Switch Positions


Battery Combine


Alternator Field Disconnect 


Maximum Voltage

48V DC

Terminal Stud Torque

140 in-lb (15.82 Nm)

Continuous Rating 


Intermittent Rating 

600A (5 min)

Cranking Rating 30 sec 


Battery Inputs


Cable Clearance For 4/0 AWG Cables

1.10in (27.94 mm)

Cable Size to Meet Ratings

4/0 AWG (120mm²)

Mounting Holes

Accept 1/4" (M6) Screw

Stud Material

Tinned Copper

Terminal Stud Size

3/8" - 16 (M10)


1.30lb (0.59 kg)

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