How to Wire a Battery Isolator
Isolators are commonly used in automobiles and vehicles, so naturally, one might find one at an auto parts store. Battery isolators are great because they serve the purpose of protecting the batteries and wiring from melt-down. When installing a battery isolator, it is important to follow a few basic guidelines to avoid unnecessary errors and ensure proper safety.
First: Notice the amperage rating
Before attempting to connect the batteries, it is important to check the relays for an amperage rating. This basically tells you how much amps the relay can handle or how much current can transfer from one post to an opposite post. Take note of this number once you find the number at the top of the relay.
Second: Specify the number of posts
Determine how many batteries the isolator can connect by finding the number of posts. For example, an isolator with three posts can connect up to four single batteries to the relay. Each battery uses the relay isolator to transfer energy back and forth in order to prevent power drainage.
Third: Install each battery, and test the connection
Next, simply locate the correct amount of batteries, and place them, one by one, inside the isolator system. After hooking up the battery terminals to the relay, look for the ignition connection, and adjust the wiring as needed. Keep in mind a true 12 volt ignition wire is found in the main power harness under the steering column inside the vehicle. Notice how the relay does not transfer power to your vehicle when at rest, even after the unit is properly grounded. In order to test out the connection, turn the isolator to the "on" position, and start the engine of your vehicle.