Odd question about battery hookup

[parallon]

Hello all. Recently purchased a barely used 2009 NorthTrail 21fbs. I have been gathering all the required equipment and making some repairs, and when I went to put in batteries, which weren't there, I noticed the heavy gauge Red and Black wire, which I am assuming runs to the AC-DC converter, and then I noticed a smaller gauge pair (black and white) with eyelet battery terminals. They run directly into the covered underbelly. Does anyone happen to know what these wires go to? I assuming that White would be Positive, and the black would be Negative?

Thanks in advance,

Mike

 

[cookie]

In the case of a white and black wire bundle white would be neutral.
But I would first want to know what they are providing power to.
Track it down.

Peace
Dave

 

[danemayer]

One skinny wire goes to the emergency breakaway switch. If the trailer comes off the hitch, the cord pulls out of the switch and battery power is applied to the trailer brakes.

 

[parallon]

In the case of a white and black wire bundle white would be neutral.
But I would first want to know what they are providing power to.
Track it down.

Peace
Dave

I know that white is neutral on AC, but black is also ground on DC so that's where part of my confusion lies. I had a thought, could those be the wires that come from the AC to DC converter to charge the batteries while on shore power?

Mike

- - - Updated - - -

One skinny wire goes to the emergency breakaway switch. If the trailer comes off the hitch, the cord pulls out of the switch and battery power is applied to the trailer brakes.

Ahh, that makes sense.

Mike

 

[parallon]

Hello all, so I plugged the trailer into shore power and checked both sets of leads with my meter, and it looks as though I am getting ~13.8v charge out of both pairs, so the only other thing I can think of is that maybe the smaller pair is somehow connected to the wiring in the Truck/Trailer harness. I haven't had a chance to verify this, but I am wondering if when I am connected to the truck only, if I will get the 13.8v out of the smaller harness only? Would this sound reasonable?

Thanks,

Mike

 

[danemayer]

12V DC power is distributed 4 different ways.

1. Battery to buss bar to 12V DC mini-circuit breakers to devices. On a travel trailer, this powers exterior components like tongue jack and stabilizers.
2. Battery to buss bar to 12V DC mini-circuit breaker to Power Converter and interior fuse box. This provides power to the interior lights, furnace, 12V side of refrigerator and water heater. It's also the path for the Power Converter to charge the battery.
3. Battery direct wire to the emergency breakaway switch that powers the trailer brakes if the trailer separates from the tow vehicle (sometimes through a separate 12V mini-circuit breaker).
4. Battery direct wire to the umbilical cord that attaches to the tow vehicle (sometimes through a separate 12V mini-circuit breaker). Assuming power out of the tow vehicle, this helps keep the trailer battery charged while towing.

One hot wire probably goes to the breakaway switch and the other to the umbilical connection.

 

[parallon]

12V DC power is distributed 4 different ways.

1. Battery to buss bar to 12V DC mini-circuit breakers to devices. On a travel trailer, this powers exterior components like tongue jack and stabilizers.
2. Battery to buss bar to 12V DC mini-circuit breaker to Power Converter and interior fuse box. This provides power to the interior lights, furnace, 12V side of refrigerator and water heater. It's also the path for the Power Converter to charge the battery.
3. Battery direct wire to the emergency breakaway switch that powers the trailer brakes if the trailer separates from the tow vehicle (sometimes through a separate 12V mini-circuit breaker).
4. Battery direct wire to the umbilical cord that attaches to the tow vehicle (sometimes through a separate 12V mini-circuit breaker). Assuming power out of the tow vehicle, this helps keep the trailer battery charged while towing.

One hot wire probably goes to the breakaway switch and the other to the umbilical connection.

Thank you. I will look into that.

Mike