Trolling Motor Wiring Guide: 12V, 24V & 36V Battery Setup Guide
A trolling motor is an important tool for boating enthusiasts and serious anglers. It is known for offering quiet and accurate navigation through coastal waters, rivers, and lakes. Remember, the reliability of your trolling motor mainly depends on the power system it relies on.
At the same time, proper battery wiring is crucial, as it ensures stable performance and keeps you away from experiencing electrical issues, such as fire hazards, overheating, and power loss. Therefore, having a reliable setup powered by trustworthy names like Renogy is critical.
Renogy is known for its unmatched contribution to marine energy and off-grid solutions, as it offers marine-grade batteries, comprehensive kits, solar panels, integrated systems, charge controllers, and inverters.
Are you a DIY boater, angler, or marine enthusiast living in the US? Searching for a comprehensive guide on 24V trolling motor wiring? Your search ends here. This article helps you choose the right battery and learn how to wire a trolling motor in series or parallel. It also outlines some actionable tips and common issues.
Trolling Motor Systems Explained
Let's first understand what exactly the trolling motor is. It is a small electric motor mounted on the stern or bow of your boat. It is considered ideal for precise navigation and fishing. This motor performs its operations quietly.
Unlike the boat's main engine, a trolling motor helps the boat move at slow and consistent speeds, thereby allowing it to troll for fish. This motor draws power from the batteries installed on the boat.
When it comes to choosing and installing the trolling motor, you get different systems with varying voltage requirements, as outlined below.
- 12V System: It is commonly used for small motors (30 to 50 lbs thrust) in kayaks and small boats.
- 24V System: This system is usually used for medium-thrust motors. It provides longer run time and delivers more power.
- 36V System: It is used to power large, heavy-duty, and high thrust motors and larger vessels.
Components Required
When you plan to wire a trolling motor, make sure that you have the following components in hand.
- Trolling motor
- Fuses/circuit breakers
- Deep cycle batteries (such as AGM batteriesand lithium batteries)
- Solar charging system or battery charger
- Battery cables and connectors
Selecting the Right Battery
The right selection of the trolling motor helps you optimize its performance. Let's compare the two potential battery types that can be used in marine applications, e.g., lead-acid (AGM) and lithium (LiFePO4) batteries.
The reason why lead-acid batteries are commonly used is their wide availability and affordability. At the same time, this battery charges slowly and has a heavier structure. Plus, it comes with a shorter lifespan.
In contrast, lithium batteries support fast charging and have a lighter physical structure. Their longer lifespans make them stand out among other battery types. In addition to this, lithium batteries are expensive, but worth using in the long run.
Series vs. Parallel Connections
A series connection adds up the battery's voltage and increases the overall voltage level. For example, two 12V batteries connected in series produce a total of 24 volts at the output. On the other hand, a parallel connection maintains voltage, but increases capacity (amp-hours). For example, two 12V 100Ah batteries connected in parallel produce 12V 200Ah as the output.
The table below shows the recommended setups for different thrust levels and boat sizes.
| Boat Size | Thrust (lbs) | Voltage (V) | Battery Setup |
| Small (Kayak, Jon) | 30-55 | 12 | One 12V battery |
| Medium (Bass Boat) | 55-80 | 24 | Two 12V batteries connected in series |
| Large (Offshore, Pontoon) | 80-112 | 36 | Three 12V batteries connected in series |
Dominate the Water: Renogy 12V 100Ah Trolling Motor LiFePO4 Battery
Ready to upgrade your trolling motor setup with serious power and smart tech? The Renogy 12V 100Ah Trolling Motor Battery is built for boaters, anglers, and off-grid explorers who demand performance, reliability, and convenience.
Why This Battery Stands Out:
- High-Performance Output: Delivers 150A continuous and 300A for 30 seconds—perfect for 12V to 36V trolling motors.
- Lightweight & Compact: Weighs just 21.83 lbs—half the weight of lead-acid batteries. Group 24 size, 1/3 smaller than Group 31.
- Built for the Elements: IP67 waterproof rating and marine-grade durability for rugged environments.
- Smart Monitoring: Bluetooth 5.3 connectivity lets you track battery health and performance in real time.
- Advanced Safety: 150A BMS with low-temperature cut-off ensures safe, long-lasting operation.
Tools and Materials Needed
Now, you are well familiar with the trolling motor system and choosing the right battery. It is time to look at the tools and materials required for wiring a trolling motor, including essential tools, recommended wire gauges, and safety gear.
Essential Tools
Before you start wiring, ensure you have the tools listed below.
- Voltmeter or multimeter
- Crimpers
- Wire strippers/cutters
- Heat shrink tubing
Recommended Wire Gauges
Different wire gauges are recommended for different voltage systems, as given below.
- 6 AWG or 8 AWG for 12V and 24V systems
- 4 AWG for long wire runs of 36V systems
Safety Tools
The protective tools you should use while wiring a trolling motor include:
- Insulated, anti-slip gloves
- Safety goggles
How to Connect Trolling Motor Batteries in Series?
As stated earlier, connecting multiple 12V batteries in series allows us to power higher voltage systems, e.g., 24V, 36V, and 48V. Let's look at each system one by one. But before we proceed, make sure that each battery in the system is of the same age, size, type, and manufacture.
24V System
Two 12V batteries will be required to establish a series connection to deliver 24 volts. Here is how to wire a 24V trolling motor battery system.
Step 1: Switch off the motor.
Step 2: Connect the positive terminal (+) of battery 1 to the negative terminal of battery 2 using a connector cable.
Step 3: Now, connect the positive (+) motor lead to the positive terminal (+) of the battery 2.
Step 4: Connect the negative (-) motor lead to the negative terminal (-) of battery 1.
36V System
Connecting three 12-volt batteries in series will deliver a combined voltage of 36 volts. Follow the steps below to achieve 36V at the output.
Step 1: Switch off the motor.
Step 2: Use a connector cable to connect the positive terminal (+) of battery 1 to the negative terminal (-) of battery 2. Use another connector cable to connect the positive terminal (+) of battery 2 to the negative terminal (-) of battery 3.
Step 3: Connect the positive lead (+) of the motor to the positive terminal (+) of battery 3.
Step 4: Connect the negative lead (-) of the motor to the negative terminal (-) of battery 1.
48V System
To achieve 48 volts at the output, you will need four 12-volt batteries connected in series. Here is how you can establish a series connection between these batteries.
Step 1: Disconnect the trolling motor.
Step 2: Connect the positive terminal (+) of battery 1 to the negative terminal (-) of battery 2 with a connector cable. The jumper wire you use must be one size larger than the lead wire of the trolling motor.
Step 3: Now, connect the positive terminal (+) of battery 2 to the negative terminal (-) of battery 3. The same requirements are for jumper wire, as mentioned in Step 2.
Step 4: Use the connector cable to connect the positive terminal (+) of battery 3 to the negative terminal (-) of battery 4.
Step 5: It is time to connect the red lead (+) of the trolling motor to the positive terminal (+) of battery 4.
Step 6: Connect the black lead (-) of the motor to the negative terminal (-) of battery 1.
How to Connect Trolling Motor Batteries in Parallel?
If you want to connect multiple batteries to increase the run time or amp-hour capacity, a parallel connection will help achieve your goal.
12V System
Connecting two 12V batteries in parallel will increase the overall amp-hour capacity, while keeping the voltage the same.
Step 1: Bring two 12-volt deep-cycle batteries. Make sure that they are of the same age, type, manufacture, and size.
Step 2: Disconnect the trolling motor.
Step 3: Use a connector cable to connect the positive terminal (+) of battery 1 to the positive terminal (+) of battery 2.
Step 4: Now, connect the negative terminal (-) of battery 1 to the negative terminal (-) of battery 2 using the connector cable.
Step 5: Connect the red lead (+) of the trolling motor to the positive terminal (+) of battery 2.
Step 6: Connect the black lead (-) of the motor to the negative terminal (-) of battery 1.
24V System
Developing a 24-volt system with an increased current capacity will require four 12V batteries. The steps for 24 volt trolling motor wiring are as follows.
Step 1: Switch off the trolling motor.
Step 2: Use a connector cable to connect the positive terminal (+) of battery 3 to the positive terminal (+) of battery 4.
Step 3: Connect the negative terminal (-) of battery 1 to the negative terminal (-) of battery 2 using a connector cable.
Step 4: Use another connector cable to connect the positive terminal (+) of battery 1 to the negative terminal (-) of battery 3.
Step 5: Now, connect the positive terminal (+) of battery 2 to the negative terminal (-) of battery 4 with a connector cable.
Step 6: It is time to connect the red lead (+) of the trolling motor to the positive terminal (+) of battery 4.
Step 7: Connect the black lead (-) of the motor to the negative terminal of battery 1.
Trolling Motor Batteries Wiring Tips
Below is a list of valuable tips you should follow when wiring a trolling motor safely.
- Always use corrosion-resistant connectors
- Utilize marine-grade cables
- Never forget to prevent wiring from vibration damage.
- Install an in-line fuse and a circuit breaker to protect your wiring and trolling motor.
- Avoid exceeding the rated capacity of wires used. Otherwise, it may cause overheating problems.
- Label all connections and wires properly. It will help you maintain the system easily.
Troubleshooting Common Issues
This section focuses on the three common issues associated with trolling motor wiring.
1. Motor Not Working
- Possible Cause: Loose connection or dead battery
- Solution: Tighten battery terminals and check the battery voltage.
2. Voltage Drop
- Possible Cause: Battery age or undersized wires
- Solution: Test the battery or upgrade the wires
3. Corrosion
- Possible Cause: Lack of protection or exposure to saltwater
- Solution: Apply dielectric grease or clean the battery terminals with baking soda
FAQs about Trolling Motor Wiring
Can I use a solar panel to charge a trolling motor's batteries?
Yes, brands like Renogy offer marine-grade solar charging systems to charge your trolling motor batteries safely while you are on the water.
What size wire do I need for a 24V system?
When it comes to 24V trolling motor wiring, 4 AWG or 6 AWG marine-grade wires are good for long cable runs and to achieve the best performance.
How long will my battery last?
Well, it depends on how much current the trolling motor draws and the amp-hour capacity of your battery. For example, a 100 Ah battery can run a 20A trolling motor for 5 hours (100/20).
Final Thoughts
Proper wiring of a trolling motor is important to ensure safe fishing and boating. Following the best wiring practices is crucial for both smaller boats and large offshore vessels. At the same time, the use of premium-quality components is equally important.
Renogy provides you with a reliable and efficient off-grid solution by offering high-quality and long-lasting marine-grade batteries, solar chargers, and other accessories, such as solar panels, charge controllers, and solar charging systems.
The discussion above has presented a step-by-step guide for wiring multiple 12V batteries in series and parallel to operate 24V, 36V, and 48V systems. You can try a DIY safe installation. If unsure about anything, call a trained marine electrician for effective 24V trolling motor wiring.
