Blue Sea Systems 7650 Add-A-Battery Kit 120A

Battery Switch Rating
Max Voltage: 32V DC (No AC)
Continuous Amperage: 350A
5 Minute Intermittent Amperage: 525A
30 Second Cranking Amperage: 700A
Battery Bank Inputs: 2
Switch Positions: 3
Connectivity: Make before break
Ignition Protected: Yes, ISO 8846, J1171
Ingress Protection: IP66 - water resistant protected against powerful water jets
UL 1107

ACR Rating
System Voltages: 12V or 24V
Continuous Amperage: 120A
5 Minute Intermittent Rating: 210A
Combine 30 Seconds: 13.6V (27.2V)
Combine 90 Seconds: 13.0V (26.0V)
Open 10 Seconds: 12.35V (24.7V)
Open 30 Seconds: 12.75V (25.5V)
Open High Voltage: 16.0V (32.0V)
Undervoltage Lockout: 9.5V (19.0V)
Undervoltage Reset: 10.0V (20.0V)
Ingress Protection: IP67 - immersion up to 1M for 30 minutes

Battery Switch Details
Stud Size: 3/8in
Stud Count: 4
Max Wire Size: 4/0 AWG
Mounting Holes: 4
Mounting Screw: #1/4in (M6)
Mounting Options: Surface mount or rear panel

ACR Details
Stud Size: 3/8in
Stud Count: 2
Quick Connect Terminal Size: 1/4in
Quick Connect Terminal Count: 3
Terminal 1: Ground (Mandatory)
Terminal 2: Start Isolation (SI) (Optional)
Terminal 3: Remote LED Indication (Optional)
Max Wire Size: 1/0 AWG
Minimum Connections: 2 positive studs and ground terminal

The Add-A-Battery system is one of the most discussed electrical items in the past 20 years. The reason this system exists is because many people are improperly using their selector switch. When you place a selector switch in the 1+2 (Combine) position you charge both batteries when the engine is running (good). However, you will also drain both batteries when the engine is off (bad). Since most people don't want to play with a switch all day they leave it on the 1+2 position (bad).

The Dual Circuit Plus battery switch prevents this issue by allowing the "On" position to connect 1 battery bank to 1 load and an isolated 2nd battery bank to an isolated 2nd load. Common example is an engine to an engine battery and house loads to a house battery. This switch only has 1 fault; you can't charge both batteries when the engine is running because the batteries are isolated. That is where the ACR comes in.

The ACR senses voltage on either battery bank and when it is above charging voltages it combines both banks automatically. This is the equivalent of switching the selector switch to 1+2 (but automatically). When the charging source is turned off and the voltage drops below the designated voltage the ACR isolates the banks leaving them as 2 separate banks again, automatically. Then the cycle repeats itself. The result is you only turn the switch on at the beginning of the day, and off at the end. You never worry about the ACR during the day. Automation is a beautiful thing. Still have questions, give us a call.