What Size Circuit Breaker For 12V Trolling Motor: Everything You Need To Know

The circuit breaker of a trolling motor generally bumps a certain current. When installing the trolling motor, you have to use a fuse or circuit breaker to prevent over current flow  which can instantly burn the motor. Trolling motors have different volts like 12V, 24V, 36V, and 48V, but what size circuit breaker for 12V trolling motor.

There are different circuit breakers out there for a trolling motor. However, for a trolling motor of 12V, we can use a 50 amp or 60 amp circuit breaker. But you have to consider some facts. If your trolling engine weighs 30 or 45 pounds, a 50 amp circuit breaker is the best, and motors over 50–55 pounds usually work best in combination with a 60 amp. circuit breaker.

Should I Use A Circuit Breaker for A Trolling Motor?

Circuit breakers are extremely safe equipment to protect your new engine. The Coast Guard also requires them for live ungrounded conductors. It works by automating opening or breaking an electric circuit to stop the electric flow. 

Here we mention some important causes,  why you should use a circuit breaker for your trolling motor:

  • Circuit breakers protect your trolling motor from overloads.
  • They help prevent fires by interrupting the flow of electricity if there’s a problem.
  • Circuit breakers can also protect your trolling motor from damage caused by lightning strikes.
  • They’re a good idea if you plan on using your trolling motor in saltwater, as they’ll help prevent corrosion.
  • Circuit breakers are relatively inexpensive, so they’re a good investment for your trolling motor.
  • When the propeller gets stuck in a submerged object (log, rock, thick seaweed, etc.) and cannot turn, the motor can use more battery power to turn your shaft. If it continues for a long time, the high current level will cause permanent damage to the trolling motor, usually causing it to fail. Here the circuit breaker plays a vital role to disconnect the connection and keep your motor safe from damage.

Overall, using a circuit breaker with your trolling motor is a good idea. It can help protect your trolling motor from damage and keep it running smoothly for years to come.

What Size Circuit Breaker For 12V Trolling Motor?

When it comes to trolling motors, the rule of thumb is that the circuit breaker should be sized at 125% of the trolling motor’s max amperage draw. 

Circuit breakers are usually rated for the power of the trolling engine installed on the boat. The amperage rating varies for different models. It can be 30A, 40A, 50A, 60A, 100A, 300A etc. You should pick the right one depending on your maximum amperage current.

For example, your trolling maximum  amperage draw is 40-45  amps, the circuit breaker should be rated at 50 amps.On the other hand if the maximum current become more than 50 ampere then you should go for the 60 ampere circuit breaker.You can’t select below the 50A range. Otherwise your motor will trip on the normal condition.

Here are a few additional things you need  to consider when choosing a circuit breaker for your trolling motor:

Weight Of The Motor

It tends to be directly proportional to the trolling motor switch current for weight. Generally, if the motor weighs around 30-45 pounds, a 50 amp circuit breaker is best and motors over 50–55 pounds usually work best in combination with a 60 amp circuit breaker.

Type Of The Motor

There are two main types of trolling motors – brushless and brushed. Brushless motors are more efficient and will require a different circuit breaker than a brushed motor.

Wire Length

In particular, the trolling motor’s 50 or 60-ampere circuit breaker must withstand not less than 10 percent of the amperage drawn by the motor. It is similar to the wire length. 

As for the wire length, if the length is too long, it will be a problem. It rarely happens on most ships. But if you face the problem, you have to consider the drag that comes from that length.


It is another crucial aspect, but for simplicity, you have to look at Volts or VDC to match the switch voltage to the battery voltage. Trolling motor batteries are rated at 12 volts each, and you can use multiple batteries when you need a higher voltage.


It means the driving force of the trolling motor. In fact, it is essential to know the traction a derailleur can provide, and using a wrong derailleur can reduce engine thrust, resulting in reduced performance.

Types Of The Circuit Breaker

There are different circuit breakers available for a trolling motor. Here we discuss the most common models of circuit breaker which are frequently used in various trolling motors.

50 Amp Circuit Breaker For Trolling Motor

You can use a 50 amp circuit breaker for various electric motors. A 12V DC 50 amp circuit breaker can be used with 30, 40, and 45 lb trolling motors. The maximum power consumption for these motors is 30 amps and 42 amps.

You can use the 24V DC and 36V DC circuit breaker with a 70 and 101 lb motor. The maximum power consumption for this trolling motor is around 42 and 46 amps. On the other hand, a 48 VDC circuit breaker for an E-Drive motor can consume 40 amps.

60 Amp Circuit Breaker For Trolling Motor

Like a 50 amp, 60 amp circuit breakers have different types. You can use a 12VDC 60A circuit breaker with 50 and 55 pounds trolling motors. In addition, the maximum power consumption for those motors is around 50 amps.

You can use a 24 VDC and 36 VDC circuit breaker with an 80, 101, and 112 lb motor. The maximum power consumption for this motor is 56, 50, and 52 amps, respectively.

Moreover, the 2 x 60A (24VDC) circuit breaker contains 2 circuit breakers that can be used with a 160 base motor.Here, the maximum power draw for the engine is around 116A. Together these circuit breakers deliver a surge of around 120A resist. 

However, as mentioned earlier, these circuit breakers can adequately protect your motors if some requirements are met. The conductor should have good insulation at around 105°C, and the maximum number of conductors will be two. When the engine is running at full strength, the voltage drop should not exceed 5 percent.

Does A 12 Volt Trolling Motor Need A Circuit Breaker? 

The circuit breaker plays a vital role in your trolling motor operation. It protects both the engine’s internal electrical system and your boat. 

Trolling motors are often prone to overload and susceptible to short circuits. Circuit breakers control this. If the trolling motor has a short circuit or overload, your circuit breaker may light up or go out.

This surge usually occurs when the trolling motor or propeller encounters additional resistance. It may happen if your propeller gets stuck in rocks or bushes. 

When your trolling motor runs at the preferred speed, it consumes more energy to overcome resistance. This increasing power may create a short circuit. If a circuit breaker is not installed, it can damage many critical engine components.

How Do I Wire A Circuit Breaker To My Boat?

Wiring the circuit breakers is easy. You have to connect it to the positive wire between the battery and motor. For wiring a 50 amp circuit breaker, you can follow the guidelines below.

Step 1: Select A Suitable Location

Choose an appropriate location for installing your circuit breaker on the boat. The circuit breaker is best installed near the batteries.

Step 2: Mount The Circuit Breaker

Use the 2 holes in the breaker base to install your 50 amp circuit breaker. It has two terminals labeled BAT and AUX. One is connected to the battery and the other to the trolling motor.

 Fig.:How to wire a circuit breaker for 12V trolling motor

Step 3: Finish Wiring

Connect the positive (+) power wire to the terminal “AUX” on the circuit breaker from your trolling motor. Then, join the terminal marked “BAT” to the switch on the positive (+) end of your battery terminal.

Final Thoughts

I think you have got all you need of what size circuit breaker for 12V trolling motor. Remember that the extension wire used for all 50 and 60 amp circuit breakers can be 5′ to 25′ long. They differ depending on their caliber. 

The choice of cable thickness from the battery to the motor is significant. That’s because it determines if the cable can handle the surge. The cord will not withstand the surge when installing an extension wire with the wrong gauge. 

The wire will overheat, and the insulation will melt if you do so. As a result, your breaker may become useless, and you may damage your trolling motor. In severe cases, it may cause a fire.

Anthony Jones
Anthony Jones

Anthony is an expert in fishing and trolling motor equipment, based in Austin. In his free time, he can often be found out on the water, perfecting his fishing techniques and testing out the latest gear.

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