"Add-A-Battery" Dual Circuit System


In stock online.
Model # 8646275 | Mfg # 7650 | UPC # 632085076504

Adding a second battery to support your new electronics or trolling motor? Charge it and use it as an emergency backup with an Add-A-Battery system.

If you are adding a second battery to support a larger stereo, a trolling motor or a new fishfinder, this kit is an essential part of the installation. The Blue Sea System Add-A-Battery™ kit packages a switch and an automatic charging relay (ACR) to help protect and maintain the additions to your boat. Both components are designed to withstand a life on the water.

Single charging source: The kit allows you to charge your new and existing battery from a single charging source; often your engine. It also helps to keep the two power sources separate so that you are only drawing power from the battery you want to. That is until one battery can no longer supply power. The included battery switch provides an emergency combine feature that can get you out of a jam.

ACR combines or isolates battery banks: The automatic charging relay (ACR), a Blue Sea Systems 7610, performs several tasks. It combines the two batteries while charging, and isolates the house battery to protect sensitive electronics while starting the engine. The ACR will share the charging source more efficiently than a battery isolator—without creating a voltage drop—and will not require additional wiring or an external regulator; installation is straightforward. Because the ACR is ignition protected, it can be installed within the engine room.

Prevents dead batteries: The included battery switch, a Blue Sea System e-Series Dual Circuit Plus™, is packed with features. While in the ON position, both house and start batteries provide power, but are separated giving power to only the circuits dedicated to each battery. This eliminates the risk of draining the start battery by leaving the stereo on too long or running the trolling motor too much.

Backup starting power: However, if there is a time that extra power is needed from the battery with a charge, the combine features allows you to draw power to start the engine or make an emergency radio call. This battery switch is ignition protected and compatible with installations in engine compartments of gasoline powered boats. It can be surface or rear mounted for a cleaner look.

Key Features

  • Allows two batteries to be efficiently charged from a single charging source without external regulators or isolators
  • Automatically isolates house battery during starts to protect electronics
  • Provides an emergency combine feature to draw power from both batteries
  • Simplifies switching for two battery systems
  • Tin plated copper studs on the battery switch provide maximum conductivity and corrosion resistance
  • Ignition protected ACR and switch; can be installed in engine rooms of gasoline powered boats
  • Multiple switch installation options

7610 Automatic Charging Relay (ACR) 

  • Nominal voltage: 12V, 24V
  • Start Isolation: Yes
  • Amperage Operating Current: 175mA (combined), 15mA (open)
  • Continuous Rating: 120A
  • Intermittent Rating: 210A for 2min.
  • Cable Size to Meet Rating: 1/0AWG
  • Terminal Stud Size: 3/8"
  • Closing voltage: 13/26V (2 min.) or 13.6/27.2V (30 sec.)
  • Opening voltage: 12.75/25.5V (30 sec.)
  • Engages: 12.7/25.4V DC
  • Disengages: 13.5/27V DC  
  • Over Voltage Lockout: 16V@ 12V, 32V@24V
  • Under Voltage Lockout: 5V@12V, 19v@24V
  • Weight: 25 lbs.

5511e Dual Circuit Plus Battery Switch

  • Switch Type: Dual Battery switch plus
  • Switch Positions: 3
  • Battery Combine: Yes
  • Alternator Field Disconnect: no
  • Maximum Voltage: 32
  • Continuous Rating: 350A
  • Intermittent Rating (duration): 525A (5min)
  • Cranking Rating (30Sec): 700A
  • Battery Inputs: 2
  • Cable Size to meet ratings: 4/0
  • Mounting Holes: 4 ¼"
  • Terminal Stud size: 3/8"
  • Dimensions: 3 5/8" x 3 5/8" 3 5/8" diameter face

Manufacturer's Documents

 WARNING: Cancer and Reproductive Harm -


"Add-A-Battery" Dual Circuit System

Name Value
Amperage 120 Amps
Color Red
ISO Approved ISO 8846
Meets UL 1500
SAE J1171
Voltage 12 Volts/24 Volts DC
Warranty Details Lifetime


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