Elec questions

[citylights]

My tow vehicle has a standard 4 pin connector.

Is it ok to run hot and ground from 4 pin connector to trailer battery for charging (using fuse in vehicle and adding one for trailer battery) Or do I need to run separate wires directly from tow vehicle battery to trailer battery (with fuse on both sides.)

I am going to get a battery tender for the trailer battery. Any issue with that being plugged into the wall charging the trailer battery AND the trailer plugged into the tow vehicle? Would it just charge both batteries? What about with the tow vehicle running?

Now for an inverter and shore power. I plan to have a shore power connection providing power to several 120 outlets on the trailer. When not connected to shore power, I may have an inverter connected to the battery and the 120 outlets. Any issue with the inverter on and trailer plugged into shore power?

I am just thinking about my wiring and seeing the possibility of multiple things plugged in at the same time... Of course I don't want to let the smoke out.

[Forrest747]

http://www.tnttt.com/viewtopic.php?p=960575#p960575

This is what Zach did.

[citylights]

Another question, can I use AC switches for a DC circuit?

[pmowers]

Another question, can I use AC switches for a DC circuit?

I actually had the same question, could not find an authoritative answer so I called Leviton customer support and they connected me with one of their engineers (great friendly support). The engineer said that most of the switches are rated for either and I shouldn't have any problems.

I considered the number of amps that are going to go through the switch. Most AC wall switches are rated for 15 A. The loads that I was going to pull on the 12 VDC circuits that I used wall switches on are in the order of 2-3 A. for lights. If you are going to be switching LED lights, the current draw would be even less. If I was switching the battery, then I would use a DC switch, but that is because of the current load.

Additionally, I considered the construction of the switches. When you open up a typical 12 VDC switch (unfortunately too easy to do) and compare it to a UL approved 110 VAC switch, the DC switch is often made of thin tin-plated crap. An exception would be the much more expensive mil-spec or industrial switches. Unless you can find them surplus, you may pay as much for one as it would cost you to use all AC switches.

I decided to use standard AC switches in my CTC (cargo trailer conversion). They are inexpensive, available in multiple forms, standardized mounting covers, sturdy. If they do ever go out, then a replacement is available at virtually any place that sells hardware.

Pat

[working on it]

How do you intend to connect the inverter to the 120vac outlets? Hardwire it? All the inverters I've seen and/or used are provided with their own outlets. In my trailer, when I need to use the inverter to supply 120vac, I simply remove an extension cord plug from the shore powered 120vac outlet, and plug it into the inverter outlet (my 110/120vac lights/appliances are all powered thru heavy duty extension cords, reconfigurable, and flexible). If you do hardwire the inverter to a common 120vac outlet, and you leave the inverter in-line with live shorepower, then the two different power supplies may not be in prefect sync (sine waves, hertz, other EE stuff), and may cause problems with electronics downline. Why chance it? And, concerning leaving the inverter on while charging the 12vdc battery, I've experienced no problems there. In fact, I use the inverter to monitor my charge state voltage. Concerning the Battery Tender: I would only leave the batteries hooked when travelling, not at home, because the single charger will sense both batteries as one, and unless both are basically identical in capacity, age, condition, stage of sulfation, and usage, then one my actually suffer from a false charge condition. Isolate one from the other. Concerning the use of AC switches for DC usage: I have been using Leviton switches for that for many years, and have had no problems in low amperage situations (I wouldn't use one to switch/power an item drawing over 10amps @ 12vdc). Conversely, I'd never use 12vdc switches for any AC wiring.

[Forrest747]

They are inexpensive, available in multiple forms, standardized mounting covers, sturdy. If they do ever go out, then a replacement is available at virtually any place that sells hardware. Pat

I chose the same reason. If they are broken or need replaced its a easy fix to goto Lowes or Home depot. So that I wouldnt have a potential little annoying stick that could poke me or worse get broken I went with the Decora style and yes Mr. Wayne it does come in black. Someone suggested just having them just inside the door to make it easier to turn off from the outside. well i did that but what i found was i have to sit up, cause the switch is by my mid-calf, to turn the lights off when laying down which is kind of annoying. if i were to do it over again i would put them on the other side of the door, closer to my head and up higher. Also the switches are thicker than the DC ones so you have to take that into account. I routed out a small pocket for the switches. In the galley I ordered the wrong led lights, that had both red and white so i got a two switch. I am happy with it.

http://www.tnttt.com/viewtopic.php?p=920747#p920747 DO NOT USE A CHOP SAW
http://s1060.photobucket.com/user/forrest74769/media/Charley/IMG00306_zpsa0b21f82.jpg.html
http://s1060.photobucket.com/user/forrest74769/media/Charley/IMG00296_zps99cf8a6a.jpg.html
http://s1060.photobucket.com/user/forrest74769/media/Charley/IMG_8686_zps51f14b2f.jpg.html
http://s1060.photobucket.com/user/forrest74769/media/Charley/IMG_8687_zps6636c67b.jpg.html
http://s1060.photobucket.com/user/forrest74769/media/Charley/IMG_8821_zps182de3f8.jpg.html

[working on it]

Someone suggested just having them just inside the door to make it easier to turn off from the outside.

I concur with having easy-to-reach lighting switches for entering a dark trailer. I put an easily reached (from either door) single switch hanging free behind the overhead fan. It powers a set of overhead LEDs (12vdc, always live).Here's photos:

[pmowers]

I put the lights right next to the door on my CT, controls the ceiling and porch lights, with no fumbling. I used the AC decor switches as well, no annoying things sticking out to catch on.

[citylights]

Thanks for the responses.

I will put the switches near the bed headboard where they can be reached from outside with the door open, or when laying down. I got decor, multi switches to use. Four switches per receptacle, one for each side. One side will control porch light, puck interior light, and reading light, with one spare for passenger side. The drivers side will control the same devices on the that side of the tear, plus the fantastic fan.

Also I will set up the inverter so that it is unplugged from the system when on shore power. I ordered a battery charger and converter combined, so that is fine on shore power or operating from battery.

New question, what side does shore power plug go on : driver or passenger?

[GuitarPhotog]

The "power tree" in every RV Park, State Park, and National Park campground I've ever visited is on the driver's side of the pad.

<Chas>