I know this topic has been discussed ad naseum. I keep blowing my 30 amp fuse when utilizing my landing gear, (Lippert). 1.My 12V batteries are new/good2. My landing gear does not need lubrication, nor is it binding in any way.3. My wiring is good.4. I am not retracting or extending gear too far. I recently installed a 12v 30amp circuit breaker, as this has been mentioned multiple times on numerous forums. Problem is, after installing 30a circuit breaker and testing landing gear, it still blew the 30 amp fuse. Perhaps i have installed the circuit breaker in the wrong place, but i don't think so. I would add a picture, but can't seem to figure out how to add a photo.Black(hot) wire leads from battery terminal and in to a circuit board,(not sure of correct terminology). This is where the 30a fuse is located. On other side of circuit board two wires,(white and white with black stripe), leave circuit board and tie in to landing gear motor. I inserted 30 circuit breaker on Black(hot) wire that feed power from battery to circuit breaker.Does this sound like proper location for circuit breaker?Does anyone thing that i need to replace my landing gear motor, as this is the only thing i have not been able to test. Thanks.Jerry

All electrical motors will draw more current when starting especially when loaded. For this reason, a lot of circuit breakers will have a time delay before opening to allow for higher than normal starting current. You may want to replace your fuse with a slow blow fuse that does the same thing. All things being equal, fuses will always blow before circuit breakers because circuit breakers are mechanical and fuses are not.Hard to say if you need new motor, if your starting current is enough to keep blowing fuses, you landing gear may be binding a little or you may have loose or bad connections/wiring. The less load (resistance)it is trying to move, the less current it needs to operate.The only way to truly tell is find out the power rating of your motor and test it unloaded and loaded to see how many amps its pulling.If you know for sure your landing gear is operating normally, and your connections are clean and tight, than its most likely your motor

The breaker should replace the fuse, and should be close to the battery, which is where the fuse should have been.

Do a simple test. Connect the 30A breaker at the battery and using even a cheap jumper cable power the motor at the motor. Does the breaker pop?

The breaker should replace the fuse not be added in series with it. If they are in series it is a **** shoot as to which will blow first.

No one so far has mentioned this so I will. How heavy is your nose. Does the motor sound strong or is it laboring when lifting the trailers nose? While not blowing fuses, my single motor setup always sounded like it was straining when lifting. Swapping to a dual motor setup and adding heavy duty reversing relays took care of my problem.

Installing 12v 30a circuit breaker for landing gear

18 Replies

richheck
Explorer
Jun 03, 2017
Many times the problem of high current draw is because of a poor ground circuit. Did you check your ground wire also?
DrewE
Explorer II
Jun 02, 2017
time2roll wrote:
Something is causing a draw in excess of 30 amps. If the circuit board is protected at 30 amps surely the equipment is designed to operate at 22 to 26 amps maximum. Besides the board itself it is just the motor so my inclination is to reinspect the wiring and connections but most likely replace the motor. A motor can seem to run fine and still have some internal short. For all know the board itself could be drawing the extra power and should be replaced.

Continuing to just replace fuses on the board is insanity. Adding circuit protection to save the fuse will be fruitless.

It could also very well be a mechanical problem, such as binding or misalignment or excessive friction in the mechanism. Motor current varies with load (and motor speed), both for DC and AC motors.
time2roll
Nomad
Jun 02, 2017
Something is causing a draw in excess of 30 amps. If the circuit board is protected at 30 amps surely the equipment is designed to operate at 22 to 26 amps maximum. Besides the board itself it is just the motor so my inclination is to reinspect the wiring and connections but most likely replace the motor. A motor can seem to run fine and still have some internal short. For all know the board itself could be drawing the extra power and should be replaced.

Continuing to just replace fuses on the board is insanity. Adding circuit protection to save the fuse will be fruitless.
myredracer
Explorer II
Jun 02, 2017
dougrainer wrote:
myredracer wrote:
According to this Lippert info. it is acceptable to replace the stock 30 amp fuse with a 30 amp breaker. Lippert specs. a fuse and breaker in series for our stab. jacks but KZ only installed a breaker. Fuse is to protect against short circuit and breaker for overload. For the landing gear it's one or the other.

Sorry, this is the problem when people have NO clue as to what they are talking about. The OP has a DIFFERENT system than the link you provided. He has a CONTROL Circuit board with a 30 amp fuse ON the board. Using a 30 amp auto reset ATC 12 volt breaker installed on the board may cause a temp overload that would burn the circuits on the board. Doug

My bad...
dougrainer
Nomad
Jun 02, 2017
myredracer wrote:
According to this Lippert info. it is acceptable to replace the stock 30 amp fuse with a 30 amp breaker. Lippert specs. a fuse and breaker in series for our stab. jacks but KZ only installed a breaker. Fuse is to protect against short circuit and breaker for overload. For the landing gear it's one or the other.

Sorry, this is the problem when people have NO clue as to what they are talking about. The OP has a DIFFERENT system than the link you provided. He has a CONTROL Circuit board with a 30 amp fuse ON the board. Using a 30 amp auto reset ATC 12 volt breaker installed on the board may cause a temp overload that would burn the circuits on the board. Doug
myredracer
Explorer II
Jun 02, 2017
According to this Lippert info. it is acceptable to replace the stock 30 amp fuse with a 30 amp breaker. Lippert specs. a fuse and breaker in series for our stab. jacks but KZ only installed a breaker. Fuse is to protect against short circuit and breaker for overload. For the landing gear it's one or the other.
pianotuna
Nomad III
May 27, 2017
Always size the fuse or breaker to the wire.

I did replace the 60 amp fuse for charging my house batteries with a 50 amp automatic circuit breaker. It has worked well for me.
dougrainer
Nomad
May 27, 2017
To answer your question. You have installed the CB in FRONT of the problem. The power goes from the battery TO your 30 CB and THEN to the circuit Board that has the 30 amp fuse. The problem is the CURRENT overload goes to the Circuit Board FUSE first. 30 amp circuit breakers will usually have a higher load before tripping. They make a CB that will plug into the circuit board in place of the 30 amp fuse. Usually when you have this type problem, it is the OEM's fault. They have NOT installed large enough 12 volt wire for the circuit. I would install a larger supply wire from the battery TO the Circuit board. The LCI install states 8 GAUGE for both Negative and Positive. If you do NOT have that Gauge, then that is part of the problem. Remember, regardless of what others have posted and complain about, IF the OEM does NOT install the correct wiring, it is NOT LCI's fault. FIX the problem, do not go around it. The 30 amp fuse is THERE for a reason. IF you bypass or modify, you may burn the control of the board. Doug
MEXICOWANDERER
Explorer
May 27, 2017
Separate post. To help some who have responded IMPORTANT

Reduction of voltage to a DIRECT current motor does NOT raise amperage. It cannot. With higher resistance and lower voltage automatically comes LOWER amperage.

The lower voltage higher amperage phenomenon occurs in alternating current motors.
MEXICOWANDERER
Explorer
May 27, 2017
Fuses are intended to protect electronic components. Breakers are intended to protect electrical circuits. A master breaker with branch fuses is standard protocol when distributing power to electronics.

Having a fuse inline with a breaker to protect an electric motor is a gross misapplication. Eliminate the fuse.

The breaker has nothing at all to do with protecting the motor. It has everything to do with protecting the electrical circuit to the motor.