Greetings from the great NorthWet...upcoming DIY build

[mlts22]

As for power, I'm doing research into seeing if I can get a second alternator on a bracket for the Transit. If this can be done, then all you need is an inverter, and you can run the microwave from the vehicle's engine, no generator needed. I want this functionality in addition to a generator so I have redundant power (so I can keep the engine running, park, nuke a sandwich at a rest stop.)

The reason for two alternators is so that the vehicle's wiring and the wiring for the house remain completely separate. This makes troubleshooting electrical faults a lot easier, plus bad things happen if trying to tap the main alternator. Very bad things, as it is PWM controlled, no D+ wire.

[skagitstan]

In theory, I like the idea of a separate alternator and split power systems, but is there enough advantage over the typical RV battery isolator approach to make it cost effective?

If we assume a microwave sucks about 1200W, that's a 100A load on the 12V battery charge system. The Transit's alternator is rated at 220A full tilt. So there should be reserve, even if we need to put a brick on the gas pedal to get the RPMs high enough.

Even counting inefficiencies (like using a car engine to power such a relatively tiny load), I'd guess the alternator and inverter is effectively the same output as a 2KW spare generator for running stuff like the micro. (assuming no other big loads.)

I may need to get re-edumacated on alternator technology, but as I remember, the D+ is mainly to fire off a charge idiot light. Am I missing something here?

I was thinking of just having a shunt based house battery monitor to track charge/discharge status and history (something like the Trimetric 2030...about $150 or so). Or maybe Magnum's ME-BMK to play nice with the ME-ARC controller for the MM-2012. (about $180)

Stan

[skagitstan]

I'm beginning to think a voltage sensitive relay (VSR) may offer the best compromise between split systems and a diode block isolator Example: http://www.jaycorptech.com/pm-220-11...tor-relay.aspx

If either side is capable of charging the other side it will (either by shore, solar, or alternator). If neither is, the sides are essentially split. A series fail-safe fuse or breaker would limit charge current above the VSR spec. A bypass relay controlled by one of the upfitter switches could combine the two systems if needed to start the car.

Comments?

Another question...My Transit order is a week old. HTF did folks actually manage to wait through the vehicle build process without going completely bonkers???
Did you ever get some sleep until the van showed up?

Stan

[markopolo]

Re: the relay or separator - try to get one that matches or exceeds the maximum alternator output

This one: http://www.cooperindustries.com/content ... 5-200.html is bi-directional like the one you linked to but it is rated higher at 200 amps.

I just got one that is similar to the one in your link. (not installed yet) It is rated 140 amps (like the one in your link) and matches the 140 amp alternator I bought. I don't think the one I got is bi-directional though. I have a manual switch in place for combining the banks but automatic would be nice.

[markopolo]

Oh yeah - sleep comes later, when you finish the van

[GuyGene]

I look forward to your progress, skag. I looked at that Truma water heater video, and wondered if something like those pipes that were shown on top could be routed under the floor on your build for heated flooring? To me, all RVs should have heated floor! Just makes sense, and I don't see why it couldn't be easily done.

I wish I had the time to build my own! Three things I'd do:

1. Heated floor
2. I NEED a very good bathroom due to physical issues! IBS, etc. due to fibromyalgia pain. I'm like the commercials where folks plan bathroom locations before they go out! I don't know if those composting types could work for me.
3. All pipes insulated.ALL the water pipes. At least so I could use my class b in below freezing temps.

[rockymtnb]

That Jaycorp Voltage Sensitive Relay is only rated for alternators up to 120 amp output, definitely not adequate for Transit's electrical output. We have the SurePower (now Cooper) 1315-200 isolator shown in Marko's link. It works reliably in our Sprinter but beware of the 1.5 amp parasitic power consumption during operation.

That parasitic consumption isn't really a problem while driving or charging off shore power when 50-100 amps of charging current are available. But if you have solar panels which output relatively low amperage, perhaps averaging 5-10 amps, over longer charging periods that 1.5 amps steals 15-30% of your solar power. A latching relay style separator such as the BlueSea 7622 would be a better choice for a new build with solar, consuming only 13 milliamps parasitic loss.

[skagitstan]

Good point! I had missed the highish parasitic current in the spec.

Needs some more thimking.

Stan

[skagitstan]

I may have found a device that handles all the issues:
http://www.sterling-power-usa.com/ProCo ... or24v.aspx

It can be programed as a bi-directional VSR, there is a 280A unit available, it has fault detection, and also will current limit if the draw is too high. Also has really low out-of-circuit and parasitic current specs and a switch controlled bypass mode..
It's a bit pricey at $288, but I may decide that it is such a small percentage of the total build price that I won't really notice the extra pain.

Further thoughts?

Stan

[markopolo]

Link to Blue Sea unit rockymtnb mentioned: https://www.bluesea.com/products/7622/M ... 2V_DC_500A

Just a general comment: look for mounting locations, and check physical dimensions of the units to see what fits.

[skagitstan]

Looks like a good possibility, maybe even better. Thanks!


I do like the current limiting on the Sterling, but that might be overkill.
Stan
edit to add: One concern could be the overvoltage lockout is above 16V. The Norcold fridge I'm looking at has a max voltage someplace in the 15V range.

[skagitstan]

Looks like this adventure is actually going to happen! Dealer called today with the VIN #, and a projected 13 April build date.

WooHoo!!!!

[markopolo]

That's exciting!
Hope April comes quick.

[Fastpaddler1]

Originally Posted by skagitstan

Hi all,
On Friday, my wife & I ordered a Ford Transit van (9500 EL HR 3.5L 3.31LS) on which we'll perform a DIY RV conversion. Been spending most of our waking (and sleeping) hours planning out the build, and how the heck we'll fit us and our Malamute. The van will replace our current smallish (~25' hitch to butt) travel trailer. Dealer estimates that it'll arrive in 10-12 weeks. Until then I will plan and .

Van will have heavy duty alternator, towing package, dual battery package and the premium leather package, MFT, etc., etc.....It'll also have the flippable 2nd and 4th window package. We're doing that with an eye to eventually replacing those with CRL torque outs when (if) they become available. I didn't really want to cut window holes.

The inside layout will be similar to the PleasureWay Plateau TS, but the bed will be fixed. We decided against a mfg built unit for a few reasons:
1. Cost. We estimate the total build, van and conversion, will be well under $70K...even very well tricked out. Labor is me.
2. We HATE the low clearance of the Plateau's running boards. Same goes for most of the other manufacturers. The Transit or Sprinter van ground clearance is already an issue we may need to address for the places we want to go.
3. We can put in exactly what we want, where we want it, with no space taken up by stuff we don't.
4. As a 3/4 retired engineer, I'm looking forward to the design and build work!

We'll be running largely solar, probably ~ 500W worth of collectors, a 2KW inverter/charger, and about 400AH AGM battery set. There will be propane for a 2 burner stove, tankless water heater, and a 19KBTU furnace (probably with underbody LP tank). Fridge will be an AC/DC only 7c.f. Norcold. Microwave will be about 900W output, and will see fairly limited use.No air conditioner desired! Current plan is for ~30-40 gallons fresh water under the bed frame, and 15-20 gray under the body. No inside shower. No black. We'll be using a composting john, likely the Nature's Head.

The van's working name is Annie.

My biggest concern with the Transit is ground clearance on the extended body, since most of our camping historically is out in the remote-ish boonies, on the fairly crappy Cascades N.F. roads. I expect to take it out roughing before the build really starts to see if this will be a significant issue. If it is, I'll think about an adjustable air-lift kit for the rear. The hitch, while worsening clearance a bit, may act as a buffer to protect the body. I may add skids or a skid plate to it's bottom.

We looked at Sprinters, but in most respects other than overhang/clearance, the Transit fits better. (Wish it had 4x4 though...) We pretty much rejected the Promaster right off...too small for our wants/needs.

I will likely post a writeup of the build as it occurs (along with 8x10 glossy photos with pictures and arrows). I didn't see a DIY section, so is any specific forum section better than General Discussion for this?

As the build proceeds, I look forward to all constructive feedback, and welcome disparaging remarks on my intelligence. I especially value "why the frack didn't you do it this way?" questions. Until then, I'll mostly lurk and learn...

Nice to meet you all!
Stan

Welcome and congratulations in anticipation of a fully tricked out and custom RV. But no shower? Won't you stop over sometimes for a few days??? OK. I have a thing about public showers and stuff at parks and rv sites. I almost died from using one somewhere in Europe(lost my sight due to an infection for several weeks). So, I guess I will have to understand different preferences. If you are going off road are you have a scatter-plate installed or I guess people call it an engine sump protector, like I had on my Toyota Landcruisher in Africa.
Keep us posted.
AL

[skagitstan]

Thanks for the welcome!

We may want to add a skid plate over the sump, as well as the fuel and propane tanks. I won't really know until I get some experience on how Annie generally handles on rougher forest roads. I don't expect we'll 'be doing any serious off-road.

As far as a shower goes: We've never used the inside shower in our old class C or current TT for anything but a place to hang wet clothes for extra water jug storage. Washed our hair with a pot of warmed up water, wet washcloths work for the rest. Our pre-RV camping background is fairly minimalist...2-3 week long backpacking trips, and living in our old VW bus up and down abandoned PNW logging roads.

We may want to put in an outside shower, but are leaning away from it. Hardly ever used the ones we've had. I may run some Pex stub lines to where we might install one, just to save rip-out work if we later change our minds.

Stan

[cargovanconversion]

I like your plans, mostly because they are very similar to mine. Except I'm porbably going for the LWB model. I'm not very mechanically inclined (as in cars) and have been researching the limited-slip issue for a while. Sofar came to the same conclusion as you and will be going for the 3.73 limited-slip with forest roads in mind.

With regard to propane, my plans have long been a propane tank underfloor and a Propex heater. Lately, I'm revisiting the issue, as a Webasto heater (gas version) or similar seems a better solution: no tank to install and no leaking propane to worry about. And comparable in price.

A little while ago, you mentioned "One thing that would REALLY help if anyone had actual well dimensioned CAD templates of the van". It may not be exactly what you're looking for, but you can download one here: CargoVanConversion.com. (2015 Ford Transit LWB)

I'll be following your adventure and good luck.

Van Williams

[skagitstan]

Hi Van,
That's a VERY impressive website you've go there!
I'm sure I'll be appropriating lots of useful ideas from there. Thanks for the effort putting it together.

I'm planning on propane for cooking as well as house heat.
Unfortunately, lead based electric storage and solar efficiency don't yet provide the energy density to do either, at least without running the engine. IMO, lithium isn't a mature enough, or cheap enough storage medium. That pretty much leaves dead dinosaurs as the energy source.
I'm reluctant to directly use gasoline for a couple of reasons:
1. The Transit gas tank (at ~25 gal.) is already smaller than I really feel comfortable with. In fact, if I can figure a safe external place to mount 'em, I'll probably add some cans or Rotopax at some point.
2. Cooking with gasoline in the house will be a non-starter, just because of stink and its own safety concerns.
So, since I need to be able to burn my eggs in the morning, I'll be installing propane. I think an adequately protected under-mount ASME tank is likely safer than storing bottles inside.

Thanks to the link to your CAD files. Your.png format down load page is returning an internal server error. The .dwg page works fine.
I've been doing most of my (rough) layouts in Sketchup, which won't import DWG (or DXF) files. It would be neat if I could try to scale a copy of your .PNG file if you have the time to look into the error.

Latest status on Annie is that she may arrive early to mid May. I will certainly be documenting how badly I can screw things up, starting with the very first hole I drill into the roof.

Stan

[cargovanconversion]

Thanks for your comments about the website. The error about the .png-file: my ISP sometimes has the hick-up; just try it again and it should work.

I agree completely with the cooking/heating dilemma. Lithium is on the verge of usable, but as you said not yet ready. I still have a little time to decide and hope things will have cleared enough to make the right decision. In recent months more user data about lithium use in an RV is being published, making things a bit more practical. Just wait and see.

Electric cooking may still be possible with a small induction cooktop (high amps, short cooking period), if you have enough battery amps and enough solar to recharge them. A separate issue about the cooktop is that I'll probably won't do a permanent installation, but store it in a kitchen cabinet so I can use it for cooking outside as well (in summer). In some situations the old Coleman stove would be sufficient too.

I have to say that an underfloor/outside Propex heater is still an elegant and QUIET solution.

Say 'Hello' to Annie when you finally meet her!

Van Williams

[stanw909]

I don't understand. Are you saying you will have no coach batteries but instead will run the engine for power generation? AGM batteries are better than nothing and can be used and stored indoors to prevent freezing and no off gassing. Solar panels are awesome if you're staying for long periods. If travelling a lot solar is not necessary. I will be very interested in how your DIY shakes out.

[stanw909]

Catalytic heaters are also great for quiet warmth , just follow the safety guidelines.