TRAVEL TRAILER BUILD JOURNAL
 Page 23

Posted: Sun Oct 02, 2011 1:58 pm    Comment from reader portable air conditioners

Dual hose portables work just fine.

Posted: Sun Oct 02, 2011 10:07 pm    Question from a reader: Brakes

You say you left the brakes on while changing the tires I wonder did they become hot leaving them on long enough to change tires or did you just stop trailer from rolling away and blocked the wheels with the 4X4?

Posted: Mon Oct 03, 2011 10:31 pm    My Reply:

I parked it with the brakes on for about 20-30 minutes.

The electrical magnet inside of the brakes never gets hot from the 12 volts. It gets hot when it is energized and RUBS (sticks) to the inside of the brake drum where it actuates a lever that moves the brake shoes. The heat is from the brakes shoes mostly and some from the rubbing of the magnet.  You could turn on the brakes and "park" it without any problems except running down the battery.

Posted: Mon Oct 03, 2011 10:49 pm    Question from a reader   RE: Brakes

Let me see if I understand, when you pulled the brake switch the trailer was sitting still so the brakes were never actuated just the magnets against the drum was holding the trailer?  Or did I miss it completely and the brakes were activated?

Thanks for the answer and by the way, nice looking trailer. 

Posted: Mon Oct 03, 2011 10:57 pm    Reply: Electric brake operation

The trailer is stopped, I pull the breakaway switch, the brake magnet powers up, the trailer rolls forward about 6 inches. The magnet stuck against the brake drum pulls the actuator lever which expands the brake shoes and locks up the wheels.

Normally, when you apply the brakes while driving, the magnet sticks to the inside of the face of the brake drum and slips because the wheels are turning. But there is enough "sticking" to pull the actuator lever that expands the brakes.

Posted: Mon Oct 03, 2011 11:09 pm    Post subject:  12 volt power center

Here is the 12 volt power center. The fuse block on the left is the incoming from the tow vehicle, thru the fuse, and out to the trailer lights, brakes etc. If something shorts out on the trailer running lights I will not lose the tow vehicle lights.

The small center terminal strip is for the brakes. I ran a separate cord to each wheel brake. The next fuse block is for the 12 volt lighting inside of the trailer. Next is the Precision Dynamics 60 amp converter/charger. The two batteries are 35 amp hour deep cycle wheel chair batteries. They each plug in via a polarized two-wire connector. I can unplug a battery and use it for my trolling motor, then plug it back in for a recharge.

Every 12 volt circuit has a 30 amp fuse. I am not concerned about over current protection. I only care about short circuit protection.