Loose connection and fire risk?

softdown
softdown Solar Expert Posts: 4,081 ✭✭✭✭
Placing here due to pertinence to off grid solar connections. Fow now anyway. 

Was operating a big winch after a snapped rear axle presented a roadside emergency. 
For those who wonder, the right rear bearing only receives axle oil when making turns in a few years of the Lincoln Town Car. Similar models also I hear. There are a large number of videos on replacing the axle shafts on Lincolns and Crown Victoria’s. Mine is a 2006. 

The negative cable to the battery caught fire shortly after it started smoking. I had to operate it a few more seconds to get the car on the trailer in a pretty bad interstate location. 

Initially I thought the winch was destroyed. Still worth it since it got the Lincoln on the trailer and down the road. 

Closer look shows the negative battery cable disintegrated at the connection on the winch body. I hope to replace the lug and use the winch again. 

First time that 18K winch was used. 

A couple other cables also experienced high heat in the insulation. The rubber insulation is subsequently discolored and distorted. But the copper wires seem relatively unaffected though still covered by rubber insulation. 

18K winch so not a cheap little thing. I believe winches have short duty cycles that I likely exceeded. The demand was unusually strong due to pulling a Lincoln uphill unto a trailer. Since the axle sheared off a floor jack was used under the right axle. This was a decent tire substitute until the floor jack stopped at the trailer ramp. Then the winch was forced to work extremely hard. Probably more than extremely hard.  Smoke developed but I was literally seconds from successful completion and persevered. 

On second thought perhaps this belongs in another area? Just thought that loose connections may be a very big deal in solar power. 

I have winched a vehicle out of several “sticky” situations. Can’t recall a hot winch or hot cables before. It is possible this 18K Vevor winch has a design defect. Or a manufacturing defect. 

I can post a pic if “needed". 
First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries

Comments

  • SumPower
    SumPower Registered Users Posts: 144 ✭✭✭
    Just curious, is the conductor 100% copper? 
    Copper Clad Aluminum had been used on some of the import winches, don't know if that is still a problem.

    I personally use a snatch block when winching as one snatch block will effectively double the pulling force, minus about 10% due to friction on pulleys and bearings.
  • softdown
    softdown Solar Expert Posts: 4,081 ✭✭✭✭
    Good question. It is supple so I would “guess” copper. 

    Vevor is a big name. Not a great name but not bad. 

    Would be of interest if the positive cable is copper and the negative copper clad aluminum. I thought it odd that the negative cable caught fire at the lug. I’m kind of assuming the connection was not tight. 

    It was a hurry up throw and go operation to get the Lincoln off the road. I’ve had stuff stolen almost immediately. I’ve had a 24,000 lb. bucket truck towed after two days. You are supposed to get three.  Perhaps the location was bad but I did get permission to park there. 

    I watched a patrolman inspect my trailer with flat tire for a few minutes. Stayed up till 4am to get it out of there. Ultimately LEO can do anything they want citing safety etc. 

    Guess I could scrape the wires and see if aluminum shows up. Got a lot going on. 
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • mike_s
    mike_s Registered Users Posts: 170 ✭✭✭
    Vevor says it draws 435 A. That's 4/0 105C copper wire following ABYC, 600 kcmil 90C following NEC. I doubt it came with anything close. They also say "The winch has a huge working current under loading, so it can not continue to rewind the cable for a long time, it is highly recommended to pause the winch every 2 meters cable rewinding to allow the motor to dissipate heat" and "If the motor becomes uncomfortably hot to touch, stop and let it cool for a few minutes." So, I'm going to say it was simple overworked.
  • softdown
    softdown Solar Expert Posts: 4,081 ✭✭✭✭
    ^^^
    Guessing I used it for ~ 6 meters. Did not get the car fully loaded. Just enough to move it safely. Had to secure tailgate to trunk latch - which destroyed the trunk latch - so far. 

    I agree with your assessment. 

    Though I find it interesting that the negative battery cable died first. I thought more power generally flows in positive cables while the negative is more of a ground. But I offer no expertise on such matters. 

    Not looking at it, I’d guess the cable is AWG1 or 2. Like a battery cable. A far cry from 4/0. 
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries