How to Hook up Dual Marine Batteries
- 1). Make certain the marine battery you are going to hook up to your existing battery produces the same voltage and amperes. Incorrect matching can result in damage to the batteries and may affect the electrical equipment in your boat.
- 2). Put on a pair of rubber gloves. You will touch battery terminals during the process of hooking up dual marine batteries.
- 3). Position the second battery next the existing battery in the battery compartment. The battery compartment on boats can easily accommodate two or more batteries. Secure the battery using elasticized straps. Wrap the straps around the two batteries, then fasten using the hooks on the end of the straps.
- 4). Attach the spring-loaded clamp on the end of a new battery cable to the negative terminal on the marine battery you're hooking up to the existing battery. The negative terminal is marked with a "-" sign or with "Neg." Squeeze the plastic-coated handles so the jaw opens, then place the jaw over the terminal. Release the pressure so the jaw closes and fits tightly on the terminal. Attach the opposite end of the cable connected to the negative terminal to the negative terminal of the existing marine battery.
- 5). Attach the spring-loaded clamp on the end of a second new battery cable to the positive terminal on the second marine battery you're hooking up. The positive terminal is marked with a "+" sign or with "Pos." Squeeze the plastic-coated handles as before, then place the opened jaw over the terminal. Release the pressure and ensure the clamp is secure. Attach the opposite of the cable to the positive terminal of the existing marine battery. You have hooked up dual marine batteries in parallel.
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