My Wiring Diagram, thoughts? Concerns?

[VTTeardrop]

Hello everyone-
This forum has been an absurd well of information. I am just starting a teardrop build and have learned almost everything from reading through this forum, the internet is a beautiful place. My main questions are about the electric system. I am very confident in simple electrical work, but only in 120V AC. I would love to share what I’ve come up with for my electric system and welcome any and all critiques and suggestions. I am going to try and be as exhaustive as possible.
First the crude electric drawing and then it will be explained:



The system breakdown:
1) Battery: I am actual still stuck on this. I am looking for an AGM, deep-cycle battery that is around 70Ah’s and can’t find any decent ones around. Any suggestions? Would this one work? http://www.batterysharks.com/SigmasTek-SPG12-90-IT-p/spg12-90it_gel12-90it.htm

2) Kill Switch - Between positive battery terminal and the PD4000
http://www.amazon.com/Battery-Kill-Safety-Disconnect-Switch/dp/B0017101BE/ref=sr_1_7?s=automotive&ie=UTF8&qid=1426947145&sr=1-7&keywords=battery+kill+switch

3) In-Line Fuse - I bought this:
http://www.homedepot.com/p/Unbranded-30-Amp-Glass-Tube-Fuse-Fuseholder-12-BP-HMK-RP/203298931?keyword=in-line+fuse
but unsure of how to install it, I’m thinking I might need something like this:
http://www.delcity.net/store/JCase-Inline-Fuse-Holders/p_800448

4) All wire from battery will be 8-Gauge, the positive wire then goes to the PD4000 from the Master Fuse and the Negative goes straight to the PD4000

5) RV Inlet Plug - 30 Amp 120V - Wired to the PD-4000 with 10-2 Wire

6) All of this will be powered by a Progressive Dynamics (PD4000) converter/inverter all in one sweet little machine
7) I will have 2 120V circuits. One will be 2 receptacles in the cabin and one will be 2 receptacles in the Galley.
These will be run with 12-2 wire and the first receptacle will be GFCI in each circuit.

For the 12V side I will have 6 circuits all run on 14-gauge wire. I have read that people recommend the 12V receptacles be 12-gauge, thoughts?
Circuit 1: Cabin Dome Lights that will be through this Rocker Switch.
Circuit 2 - Cabin 12V Receptacles
Circuit 3 - Fantastic Vent Fan
Circuit 4 - Cabin Reading Lights with built in Switch
Circuit 5 - Galley Receptacles
Circuit 6 - Galley Lights (I might use the Reading Lights so I don’t have to wire a switch in )

9) All these Circuits will be run through the PD4000 and through ATC-style Automotive fuses
10) All the 12V circuits neutral side will come back to a common ground bar and the wired directly to the Neutral battery lug. Is that correct?

(I have links to almost everything that I wanted to make hyperlinks but I am not sure how to do that, if you are wondering about any of the specific products I will gladly post the link)

Questions:
1)How is the Rocker Switch installed? My walls are only ⅞” thick and the switch is 1.25” deep behind the plate.
2) Should it just stick out of the wall? Do I need to buy different switches?
3)Suggestions on what kind of battery and where to buy?
4)Do I ground the battery directly to the trailer or the PD4000?
5)If you suggest 12 gauge wire for the 12V receptacles, do you just strip Romex so it is 3 individual wires and go from there?
6)For the neutral side of the 12V system, does the common ground bar go to the PD4000 or to the battery?
7)Am I horribly wrong in any area? All areas?

I apologize for the wall of text but I would really appreciate it if any of this is looked through and critiqued. I also hope this can be of some help to someone out there. All the best

[daveesl77]

On electrical systems, whether DC or AC, consider your loads, run length and isolation needs. A good safe load on a 12v DC circuit is about 15 amp. 14 ga wire is rated for 15 amp, 12 ga is 20, and so on. Use stranded wire, not romex like in a house. Tin (solder) all connections or wire ends. 12 volt uses positive and negative. 120v AC uses hot and neutral and ground. When designing for electrical loads, depending on the location, we seldom add up all the devices on the line to get the need. Instead we use a percentage. A refrigerator may use 8amp, but it only runs about 25% of the time. A coffee pot uses 10 amp and may well use that 100% of the time. You might have 10 LEDs in your cabin, which combined would require 20 amp, but would you have them all on at once? Probably not even close.

Look at your cabin lighting. You have 2 separate circuits to feed a couple of lights. Not sure the type, but say you are going incandescent tail light, but probably something like LED. Anyway, a 25 watt tail light is about 2 amp. So, using that, to push a single 15 amp circuit, with all devices on at the same time, you would need 6-7 tail lights going at once. I use a 15 foot roll of 300 LEDs that burn 2 amp @ 12v. This roll of lights makes my canopy look like a carnival. So, to max out a single, 15 amp circuit, I could run 90 feet of LEDs, that would be 1,800 LEDs, not something I or my neighbors would want me to do.

What I'm getting at is doing separate circuits for every device does not make it safer, just makes it more complicated and costly. My 25' travel trailer had four 120v circuits and 4 12 volt circuits. My pop up truck camper had 2 of each. My 48 foot sailboat had two 120v, one 240v and ten 12 volt - it also had a ton of electronics onboard. My trailer build will probably have two 120v and three 12v.

For your disconnect, the one you picked works fine, but you may want to consider a marine type, dual battery switch. You'll find them at an equal price to the single. They come in nice if in the future you increase your battery needs.

http://www.amazon.com/Attwood-4-Way-Battery-Selector-Switch/dp/B0000AZ7X6/ref=sr_1_4?ie=UTF8&qid=1427047722&sr=8-4&keywords=battery+switch

Something I would add, if you plan on being able to charge your trailer from your tow vehicle, is a battery isolator circuit. This keeps your trailer from killing your tow battery. With my truck, I have a relay that only engages the trailer charging system if the truck ignition switch is on. I also will use a diode isolator to keep one trailer battery from draining the other trailer battery, unless I have used the above mentioned switch to tie them together. However, the way I designed my circuit is if the need arises I can charge my truck from my trailer.

On your GFCI, having two separate circuits is a good idea. Be sure to get the "pass thru" units, that way the first one can protect several in line. The thing to be aware of in your 120v circuits is the load and what type of load. A coffee pot is 15 amp, a microwave is 10-15 amp, a small AC is 10-15 amp, a dorm type fridge is 5 amp, etc. A standard GFCI is rated at 15 amp, that includes all devices in line. So, depending on your needs or desires, you might find you need more 120v.
dave

[tony.latham]

I'm a 12V guy so won't go beyond that. You need to put your main fuse as close to the battery as possible.

I don't have a problem with your 14 GA wire for the 12V runs. Your fan will pull 4.5 amps at max. My 12V electric blanket pulls 4 amps and my DVD player pulls 4 if I recall. 12GA wire to your recepticles? It'd be hard to argue against that thought, but it depends on how many amps you're going to draw from them. Obviously, with my amp draw, I don't need it.

T

[MtnDon]

Yes that DC fuse should be connected closer to the battery. Next inline would be the disconnect switch, if you want to use one. I have to admit I am not 100% familiar with the PD converter/charger. If there are two battery connection leads, one for taking power from the battery to the 12 VDC distribution system and a separate line for the charger to battery connection, then I suppose a disconnect in the DC distribution lead could be handy. But if there is only one wire between battery and the PD I would think about whether a disconnect is a good idea or not. With only a single wire pulling the disconnect would disable the battery charger as well.


Re wire and fuses.... size the wire to the maximum current flow for the panned electrical devices. In the case of AC that means 14 gauge wire if the receptacles are 15 amp; 12 gauge if for 20 amp. Then once the wire gauge is picked the fuse or breaker size is picked to match the maximum capacity of the wires. The rule is the same with DC; match wire to load and match fuse to wire. The fuse is to protect the wire not the lights or other devices. A TD is small enough we do not have to be concerned with voltage drop so there is no reason to oversize any wires. The exception might be if a PV solar system was planned.... in that case the wires from PV to charge controller and then to the battery may be oversized. One other exception would be the battery to inverter wires. I advise to oversize those as much as your wallet can afford. But I did not see an inverter so no bother with that.

5) RV Inlet Plug - 30 Amp 120V - Wired to the PD-4000 with 10-2 Wire

Probably a typo, but that should be 10-3 wire.


IMO, many DC circuits instead of one or two have the advantage of making it easier to troubleshoot. Also easier to add new stuff when you think of extras after you are done.


There is no harm, in fact there is lots of good, if you connect the battery negative to the trailer frame. The PD also has a negative / chassis connection. The ground buss can be connected to either the PD negative DC or to the battery directly. Myself, I'd choose the battery; battery ----- ground buss ---- device/light. The drawing makes it look like negative and positive wires are run separately. It is best, simpler, IMO to run a pos. and a neg. to each light or device.

[Esteban]

I have not yet installed my teardrop's electrical system. I have purchased most of the parts I plan to use. For the most part my plan is similar to yours.

My plans differ (or expand on your plan) because I plan to mount a solar panel on the roof to help charge the teardrop's battery. I also plan to run a 7-way RV wire from the trailer to the tow vehicle in part to be able to charge the teardrop's battery from my tow vehicle when traveling.

I bought the same Kill Switch you're using for an on/off switch between the battery and the PD 4045. As others have written your fuse, or a circuit breaker, should be on the positive cable near the battery.

I plan to use a 12 gang screw terminal block to connect each of the teardrop's dc circuit positive wires to the corresponding dc circuit wires in the rear of the PD4045.

You do not show outside porch lights in your plan. Is that an oversight?

sailorsams.com sells single and dual Euro Rocker Switchs that have a 0.78" recess that may fit in your walls. I'm using them. They also have a nice selection of LED reading lights.

Your "5) RV Inlet Plug - 30 Amp 120V - Wired to the PD-4000 with 10-2 Wire" should be use 10-3 wire instead.
Suggestion: Amazon.com sells a Furrion F30INS-PS Square Non-Metallic 30 Amp Inlet with Stainless Plate 30 amp inlet for $42.98. It's pretty economical and has a LED that lights up when it's connected to shore power.

As I wrote above I'm using a 7 Way Plug Inline Trailer Cord to connect the wiring from the teardrop to my tow vehicle. Under the trailer frame I'll mount a Stud-Type-Plastic-Junction-Box/p_790202 to make the initial under the trailer wiring and any subsequent upgrades and or repairs easier to do. I bought a 25' length of the 7-way wire so it can be spliced at the junction box and continue rearward to the electrical compartment in my upper galley area. The 10 gauge dc+ charge wire will be connected to the PD4045. The other wires for the trailer lights from the 7-way wire will be connected to a second terminal block, and from there will be wired with trailer connectors to the galley hatch.

DelCity.net sells a variety of Trailer-Connectors wiring loops with plugs that are handy for wiring the DC circuits (in my electrical plan from a terminal block in the electrical compartment to the hatch wiring) to power your tail lights and the overhead galley light(s). The plug(s) for the connector(s) can be accessible/exposed under the galley hatch near the hurricane hinge should you ever need to disconnect them.

Bonus Idea for added safety on the road. Consider installing a USA-MADE-TecNiq-Red-HI-Mount-Center-Brake-Turn-ID-Bar-11-LED-Light-Trailer-Truck LED light high on the center rear of the trailer.

Adding, the PD4045 is a converter. It is not in inverter.

[VTTeardrop]

Concerning the fuse: does everyone mean that it should go before the kill switch? That’s easy and thanks for pointing that out!

For the shore power I bought a 30-Amp 120V plug so there is only 3 prongs in it and 3 wire attachments in the back. Wouldn’t that be 10-2 (3 wires including the ground)?


Dave:
Do you suggest stranded wire for everything? Even the 12-gauge wire and just run 3 separate wires vs. all three in romex?
That makes sense simplifying the circuits. Maybe run all my lights on one circuit but keep all the receptacles separate?
The dual disconnect makes a lot of sense, I haven’t bought one yet so I think I’ll go that route. Thanks.
There will be a couple different cars that pull this so I am not sure if I’m going to go down the car charging route. I was hoping that with the PD, plugging it in and keeping the battery charged wouldn’t be too much of a hassle.


Tony:
I think I’ll use 12-gauge for the 12-volt receptacles just to be extra safe.


Don:
Good point about the disconnect. Yes I suppose it would disable to battery charger as well. I guess I see the kill switch as a kind of final safety switch to shut most of the system down. I will look into that.
Thanks for putting the wire sizes to AMP load in clear language that all makes a lot of sense.
Ok, I’ll attach all the negative/neutral 12V bar to the battery.


Esteban:
No, porch lights weren’t an oversight, I guess I don’t see their utility in my case. I have done a ton of tent camping and I don’t see why I would need a porch light. Maybe to use as a light while hanging by the fire or to play cards etc.. with? I will be carrying a propane lantern or 2 so that was going to be my external light source plus headlamps. Where do you see their utility coming into play?
Thanks for that link to those rocker switches, perfect!
Thanks for the delcity links and that braker light, looks good I will try to add that for sure!

Thanks for all the input guys I will certainly be making all of these changes?
Any thoughts on batteries? What do you guys use?
Also - how do I make a set of words or a word a hyperlink?

[MtnDon]

Also - how do I make a set of words or a word a hyperlink?

It is done with some BBC, Bulletin Board Code.

I can do it quicker than I can explain but here goes.... I hope this is clear.

First, for an example I will use this url as the one we want to link to...
http://www.solar-electric.com/mosu300wasiw.html
We could simply paste that in the message like many do.

We will use the URL button that appears right above the area where we write our message before posting.


Note: To make everything visible I have to change some characters to make everything visible to you. If I typed the line exactly as would be used to make that one word "suresine" be a working link, you would not see the code, just the word suresine in light blue, signifying there is a link.
So I will replace the square brackets [ URL ] with these { URL }
To make it work replace the { and } with [ and ] and it will be a working link.


To start, type the word we want to be the visible word that is the link. Like this...

Suresine

Highlight the word and then click on the URL button.
We will then have this... (again I will replace the square brackets with the parentheses. So we end up with this....)
{URL}Suresine{/URL}

Next place the cursor after the L in the {URL} and press the = key. So we then have....
{URL=}Suresine{/URL}

After inserting the = sign the cursor will be just after the = sign. Leave it there and Paste the url we want to have linked to.... (the url is the one to .... http://www.solar-electric.com/mosu300wasiw.html

After pasting the line then looks like this....
{URL=http://www.solar-electric.com/mosu300wasiw.html}Suresine{/URL}
Remember I have substituted the { and } for the [ and ] that we use to make this work.


Try one and use the preview button to see if you have it right.

[daveesl77]

Keep your 120v neutral and your 12v negative separate. 120v ground and negative can share. Some States (for the actual power supply - like the campground) allow the neutral and grounds to be on the same line, others they must be separated. While the separate systems can be potentially safer, they can also introduce a potential problem by allowing the hot and neutral to be switched. Best practice is to keep the neutral and negative on different terminal strips.

I would always use stranded wire over solid on any moveable structure. Just be sure to "tin" the wire ends, as this will help to reduce any potential future connection problems or corrosion. Actually, I solder every joint except wires going on a terminal strip, those are tinned as usual. A good way to do wiring in a trailer is to use good 3 wire extension cords, 12 ga or bigger. This assures you of having a flexible, color coded and double covered wiring system. Use like orange colored for 12v systems and yellow for 120. Be certain to ALWAYS mark your wires as you pull them so you know what each goes to, make a circuit diagram and mount it in a safe place for future reference.

While you may not want a porch light, I would set up some type of exterior 12 volt receptacle, weather rated, just for future use. You can also pre-run wire during your build stage, leave it disconnected but location determined so you have it if you want it.

3 wire recept and wiring is normally referred to as something like 12-2 w/ground or 10-2 with ground. That means 3 wires total. 10-3 with ground means 4 wires. Also remember, with North American 220v you have 2 hot legs, no neutral and a ground. Each leg is 110 and the ground becomes the neutral.

While many people won't agree with me on this, I always bring a 2' copper ground bar with strap that I drive into the ground. I then attach that to my trailer frame with some 12 gauge wire to act as an earth ground. This isn't for lightning, but instead to counter any doinks in the campground power system, not an urban legend saw it on my dad's trailer once - 120v electrified trailer skin, the campground had reversed their hot and neutral, damn near killed my dog.

dave

[Dale M.]

If one is versed on proper procedures and with proper crimping tools connections do not have to be soldered.... Actually solder make wire at connection more brittle and more susceptible to breakage, even in aircraft and all automobiles and lost of other industries solder connections are not used any more.....

A corrosion preventive (dielectric) grease that keeps oxygen out of connection prevents corrosion and a proper crimp tool with changeably dies in necessary.... Throw away those $7.00 auto parts store crimpers and get good $30-50 set of ratchet crimper with dies for insulated connectors and non insulated connectors....

This tool is not your friend....



And this is what you want minimally (better) ...



Then these ratchet styles are BEST...



Get set with changeable dies, one set for insulated terminals (oval dies) and one set for non insulated terminals (indented)



And with indenter dies and non insulated terminals be sure terminal/connector is oriented in die correctly (split in terminal barrel away from indent post or split towards rounded portion of die if you prefer) if you do not do it properly this is why crimps fail.... ...

Actually if you want failure proof, use non insulated terminals a corrosion preventive grease and heat shrink along with proper crimp dies ...

Dale

[H.A.]

- 120v electrified trailer skin, the campground had reversed their hot and neutral, damn near killed my dog.

dave

A reversed 'hot and neutral would have no affect upon ones trailer skin provided the trailer were correct in its wiring, and no faulty appliances plugged inside the trailer.

Perhaps years past folks confused grounding conductor with grounded conductor making connections interchangeably ??

A 'hot skin' would also indicate the campground receptacle were not grounded, or the trailers appliance cord (I am guessing a trailer could be considered an appliance... Interesting question??) had a faulty grounding conductor.

[MtnDon]

While many people won't agree with me on this, I always bring a 2' copper ground bar with strap that I drive into the ground. I then attach that to my trailer frame with some 12 gauge wire to act as an earth ground.

This extra ground earthing rod can create more problems and danger that it could possibly ever solve. It is against the US national electrical code. If we are worried about there being a fault in the campground electrical connections buy and carry a simple tester that will indicate faults right at the outlet.




If you tin the stranded end of a wire haven't you just made it more like a solid wire?

Dale is correct; soldering is old technology and crimped fittings done with the correct tools is the best modern way. Better connection and less bother. Times and methods change.

[MtnDon]

5) RV Inlet Plug - 30 Amp 120V - Wired to the PD-4000 with 10-2 Wire
Probably a typo, but that should be 10-3 wire.

and

3 wire recept and wiring is normally referred to as something like 12-2 w/ground or 10-2 with ground. That means 3 wires total. 10-3 with ground means 4 wires. Also remember, with North American 220v you have 2 hot legs, no neutral and a ground. Each leg is 110 and the ground becomes the neutral.

and

For the shore power I bought a 30-Amp 120V plug so there is only 3 prongs in it and 3 wire attachments in the back. Wouldn’t that be 10-2 (3 wires including the ground)?

Wire can be confusing and it doesn't help when I make an assumption and don't explain it. For the connection from the RV plug to the PD unit my thoughts jumped immediately to how I would wire that. I would use a short length of wire something like the flexible wire that is used as the trailer to shore connection... a heavy duty ext cord more or less.Like this.... It is stranded and flexible, available by the foot; just buy what is needed. I would not use the wire that would be correctly called 10-2 (plus ground) as 10 gauge solid wire is very stiff to work with.

My apologies for making the issue more confusing.

[Esteban]

The Little Guy forum has an ongoing discussion about (paraphrasing the discussion title) How to make a Fantastic Fan more efficient - 7350 model or upgrade kit that is very worthwhile reading. The new 7350 model has 13 speeds and uses much less power than the previous three speed Fantastic Vents (Fans) use.

There is now a retrofit kit available to change an installed three speed Fantastic Vent (Fan) to modify/upgrade it to a more efficient 7350 vent. Amazon.com sells the Fan-Tastic Vent Upgrade to Model 7350 Kit too.

The 7350 at its lowest speed uses just .2 amps. At its highest speed it uses 1.9 amps. This can help extend your camping time before your battery needs a recharge.

If you are building a new teardrop you can buy a 7350 Fantastic Vent (Fan) so your battery power lasts longer. I've linked to www.rvvent.com because they offer low prices, free shipping, and customization of the fans that no other sellers I know of can do.

[VTTeardrop]

Don -
Thanks for the hyperlink info, got it! My posts will now be way more slick!!
Great link for the 10 gauge wire to use for the shore power, I will definitely use that instead of a Romex equivalent.

Dale -
Yeah I was hoping to not have to solder anything and just crimp the terminals. I’ll make sure to get a good crimping tool.

Esteban -
I wish I posted all of this before I bought the fan! Good to know they have the retrofit kit out there, I’m keeping track of my expenses and if they aren’t too crazy at the end (wishful thinking? haha) I’ll get that.

[daveesl77]

Tinning the end of a stranded wire is a time-tested and NASA/NSF/NRC approved method of connection. It does not make a stranded wire into a solid wire. With that said, using a proper crimping tool and connectors is a very, very good way to attach wires. Unfortunately, most people do not have the tool and buy the connectors at Walmart. By tinning the wire you actually create a better bonding surface (but less conductive) than using thin, multistrand wire raw.

I will give it that a ground rod can possibly bring a lightning surge into a camper, but no more so than having steel legs on the ground itself. It is NOT dangerous and I would love to see the section of the code that says so.

If a circuit has a hot and neutral reversed and no grounding, and if the unit has a bonded neutral and ground and the unit itself is NOT tied to ground, then yes you absolutely can electrify the skin and all metal parts as the normal neutral ground would now be the hot side.

I will defer to other comments on this and there are lots of ways to do stuff.

dave