Inverter - better to order factory or do aftermarket?

[BAB]

I listened to Lewster. All these choices really have to do with HOW you'll use your trailer, but the lure of operating virtually every single 110V outlet won out and I did the Magnum MSH. Yes, I did add 4 big 6V Lifeline AGM's, and yes, you do have to add a sub-panel and wire in each circuit you want to operate through the Magnum...BUT, having had just a shakedown cruise with the new Classic, I can tell you that this inverter/charger -- coupled with 600W of solar panels, really is the ultimate in convenience and "off the grid" option.

[DHart]

Awesome comments, everyone. Much to consider.

BAB... does wiring in each circuit from the inverter involve opening up the aluminum wall panels in every area of the trailer that one wishes an outlet from the inverter? If so, that sounds like major and very costly work?

First, let me say that I know almost nothing about RV electrical circuits. Couldn't the inverter be wired to the existing outlets and have them fed by either shore power, battery inversion, or solar?

Deciding my inverter and solar power needs is inextricably intertwined with the costs involved in upgrading systems, so knowing something about the approximate costs will likely influence what I decide my inverter needs will be.

[AnnArborBob]

Originally Posted by DHart

Awesome comments, everyone. Much to consider.

BAB... does wiring in each circuit from the inverter involve opening up the aluminum wall panels in every area of the trailer that one wishes an outlet from the inverter? If so, that sounds like major and very costly work?

First, let me say that I know almost nothing about RV electrical circuits. Couldn't the inverter be wired to the existing outlets and have them fed by either shore power, battery inversion, or solar?

Deciding my inverter and solar power needs is inextricably intertwined with the costs involved in upgrading systems, so knowing something about the approximate costs will likely influence what I decide my inverter needs will be.

Based on your stated level of knowledge about electrical systems, I would initiate a email or phone conversation with Lew Farber (Lewster.) He is by far the most knowledgeable person on this forum on this topic. I believe his contact information is in his signature line (if you can't find it, PM me and I'll give it to you.)

Of course, you first need to decide how you plan to use your trailer before you know what to get (and of course, the budget comes into play at some point.) If you don't plan to camp "off the grid" much (i.e., stay in parks with electrical hookups), then you don't even need an inverter. But if you will do a lot of boondocking you will want to have a beefier battery system than Airstream provides, as well as an inverter and either a generator or solar panel system.

[BAB]

Before you go any further with this, you might want to check out the process for installing a Magnum MSH inverter: http://magnumenergy.com/wp-content/u...Series_Web.pdf
IF you have little to no experience with electrical stuff, I would NOT recommend you take this on without someone who does -- who could check out/help you with the process.
But, in response to your question about "opening up the aluminum wall" -- the answer is a qualified "NO". Your main chore is figuring out how close you can put all the piece parts -- inverter, batteries, sub-panel as close as you can to your existing main electrical panel. My trailer's main panel was just underneath the closet...which is where I put the sub-panel. The reason I qualified the panel part is that I did have to run 120V cable from the main panel to the inverter -- which in my case was on the opposite side of my trailer. i did this using conduit mounted right up against the belly pan.

[lewster]

Some clarifications that I added to post 20 that was on another thread.

Originally Posted by WindyJim
General comments: Using your batteries to heat water can really suck your batteries down. If you use a 1000 watt microwave running off an inverter, you are discharging your 12 volt batteries at the rate of 1.4 AH (ampere-hours) per minute, or 84 AH per hour. Battery discharge is measured in amp/hours (A/H). If you wish to obtain amp/minutes, divided A/H by 60. You then have amp/minutes.There is no measurement for battery discharge called amp/hours per minute I believe the fans draw about 3 amps each when running, so the two of them add another 72 AH discharge, per 12 hours (if they are running constantly and not cycling on and off via thermostats) (142 AH per 24hours). I believe the batteries you referenced have a capacity of approximately 84 AH each (when new) (total 168 AH) and I think the guidelines are to not let your batteries go below 40% of capacity (if so that means you only have 100 AH per day available for use, excluding solar generation).The generally accepted rule of battery discharge is a 50% depth of discharge, which for Interstate Group 24 liquid cells would be 80 amp/hours of usable capacity.

You state the solar was putting out 10 amps at 12 volts. That may be the max, with less in the morning and tapering off in the evening, going to nothing at night. Lets say that effectively you produce 10 amps for 10 hours per day, or 100 AH per day from your solar (more in summer, less in winter). No solar charging system puts out a consistent, continual amount of power during a sunny day. There is minimal charging from dawn that increases with the sun's azimuth, and hence the solar radiance that the solar array receives and increases to 'solar noon' which is generally 2 hours before and after peak sun angle. If one assumes a 10 amp maximum solar output during solar noon, then the projected output of this system would be approximately 70-80 amps including 10 amps/hour during solar noon and a tapering of this amount for the remainder of the day. Let's call it 80 amp/hours of solar charge per day. This is assuming a summer sun pattern.

If you have incandescent lights, they draw about 5 times the power of LED lights, so depending on how much lighting you are using they can suck the batteries down too. To heat a quart of water from 60 degrees up to boiling (without boiling) takes 7.4 AH (continuing to heat it with 1000 watt inverter would be adding another1.4 AH per minute). Don't know where you got these figures from, but there are few electric kettles that will run from a 1000 watt inverter, as many have 1200 or 1500 watt heating elements. And remember, there is an increase in the load by a factor of 10 going from AC to DC, so a 1000 watt heating element appliance (8.3 amps) would draw 83 amps plus 15% for inverter inefficiency or a total of almost 100 amps from the batteries for each hour of use, That translates to 1.7 amps for each minute of use that will be coming out of the battery bank.

All that said and done, I’m a believer in using the propane stove to heat water, and run the fans and lighting judiciously. A heavy overcast day can mess up your anticipated solar generation. Don’t let the batteries get too far discharged. Make sure they have the plates in the batteries complete covered (by adding distilled water if necessary). You can play around with the numbers, but still see that without additional power being supplied you still have to be conscious of your rate of consumption. This is good advice for any system.

[switz]

The #10 wire the factory pre-positions for their solar system is just barely adequate for their 106 watt system. Any larger solar system will require much larger diameter wire to reduce the DC voltage drop.

[gecko]

All good! But one observed fact for us is that changing from halogens to LED's resulted in a 10 fold (rather than 5x) reduction in amp draw. The 14 main cabin lights drew about 14 amps/hr when halogen, but only 1.4 amps/hr when we switched the bulbs to LED. Of course, dimming them reduces the power consumption even more.

[DHart]

Originally Posted by switz

The #10 wire the factory pre-positions for their solar system is just barely adequate for their 106 watt system. Any larger solar system will require much larger diameter wire to reduce the DC voltage drop.

Lou... would having the factory #10 pre-wired provide a good (easier) upgrade routing path for heavier line later?

[lewster]

Originally Posted by DHart

Lou... would having the factory #10 pre-wired provide a good (easier) upgrade routing path for heavier line later?

Nope! It follows thru strain relief and bulkheads and can't be pulled thru. Besides, it's much much easier to run new solar cable by the most direct route to keep the length to a minimum.


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[switz]

Since everything the factory preinstalled for their solar system is undersized for anything larger, the prewiring becomes useless. As Lew stated above, it can not even be used for a pull wire. I have photos of my unit on the assemble unit before the insulation went in the the wire runs went through the ribs. If any wires would have to be replaced in the future, I think the inner skin would have to come off to provide access.

All our controls and equipment were placed elsewhere to keep the DC wires as direct as possible. Our control center shows in my avatar and the refrigerator space provided access to the backside of that wall. The TriStar charge controller panel is top left with the Magnum remote below it and the Thermostat below the Magnum control head. The SeeLevel display is above the clock. The Magnum MS2812 resides where the factory inverter was located and the new battery will be within inches of it under the sofa.

The original battery install used 4-0 copper wire (about as thick as my thumb) and was routed as short as possible. When reading installation manuals, one sees that five feet or less is preferred to reduce voltage drop. Longer runs require even larger diameter wire which becomes ever more difficult to work with as it is so stiff.

[DHart]

OK... thanks guys for all the wonderful advice! Much to consider now.

[AWCHIEF]

Just thinking, is it possible to order a new trailer all prepped for an inverter but without the inverter installed?

[idroba]

As far as I know, all modifications and special orders are $500 each, so there would really be no savings.

[WayneS]

Originally Posted by lewster

And depending on the size of your battery bank, you can start and run a 15K BTU roof A/C with a Honda 2000 watt generator and a Magnum MSH3012-M hybrid inverter. It will seamlessly supplement the output from the generator to 'fill in the gap' for additional amperage when the A/C starts.

Many custom electrical options exist if you think just a bit 'out of the box' and consult someone with the knowledge and experience to point you in the right direction.

We are about ready to order our first Airstream (and first travel trailer) and I really like the ability to run the a/c with one Honda eu2000i generator.

Should we order it without an inverter and have the Magnum MSH3012-M installed after delivery? Will the factory batteries work with the generator and inverter to start the a/c compressor?

I think that I like the idea of the factory putting any holes in the top of the trailer.

Should I not worry about that, order it without solar also, and have all of the upgrades done together?

We want the ability to boondock but really don't know what we need yet.

[lewster]

Originally Posted by WayneS

We are about ready to order our first Airstream (and first travel trailer) and I really like the ability to run the a/c with one Honda eu2000i generator.

Should we order it without an inverter and have the Magnum MSH3012-M installed after delivery? Will the factory batteries work with the generator and inverter to start the a/c compressor?

I think that I like the idea of the factory putting any holes in the top of the trailer.

Should I not worry about that, order it without solar also, and have all of the upgrades done together?

We want the ability to boondock but really don't know what we need yet.

If you're considering using a Magnum MSH3012-M as a supplement to a Honda 2000 for A/C use, then it is pointless to order the factory inverter as the hybrid inverter requires some extensive re-wiring of your circuit breaker box.

Also, Magnum recommends a battery bank of at least 400 amp/hours for proper operation of the hybrid inverter during heavy use like A/C operation. The factory solar is also not necessary, as any properly sized solar charging system will utilize new, heavier cabling for the effective charging your larger battery bank.

If a new solar charging system in installed, it will introduce NO HOLES into your roof if properly mounted!

[DHart]

Originally Posted by lewster

If a new solar charging system in installed, it will introduce NO HOLES into your roof if properly mounted!

Lew... is this true even if there is no factory solar panel installed?

[lewster]

Originally Posted by DHart

Lew... is this true even if there is no factory solar panel installed?

This is true ESPECIALLY if there is no factory solar. Airstream places 4 holes per panel into the roof for their heavy lag screws and another penetration for their solar cable. That alone could be 9 holes with a 2 panel system......and they don't go out of their way to really seal any of them especially well!!!

When I install solar on an Airstream, there are NO HOLES from the solar charging system on any trailer that has a fridge roof vent, as I use this as the pathway for solar cable runs in and for cell/WiFi antenna cables out. All panel feet are bonded to the roof with 3M VHB tape and SikaFlex 221 with no screws used.

If a Jack digital TV antenna is used to replace the old Winegard crank-up unit, there will be a new hole for the rotational mechanism. THAT'S IT!

On smaller trailers with no fridge roof vent, there will be ONE HOLE under the combiner box for the solar cable run that is triple sealed and WILL NOT LEAK!

[DHart]

Lew... thanks for the info. It certainly looks like there is no benefit to be derived from purchasing factory solar/inverter systems, if one wishes to have either upgraded from that.

That's essentially what I wanted to know all about by starting this thread.

[ckottum]

Unless the factory solar is all you need, primarily for lights, entertainment systems, and furnace and vent fans. It provides enough to recharge the factory AGM batteries by noon on sunny days. A generator runs the air conditioner and recharges the batteries on overcast days, and the propane system heats the trailer, hot water, and range/oven. The factory solar also keeps the batteries charged when the Airstream is not being used.

Our Airstream was on the lot with factory solar and inverter and we're glad to have it. It may not be for everybody for their own reasons, but is certainly a very usable system. The only upgrade we are considering is one size larger batteries when these wear out, the solar output is plenty but the battery storage is where we may come up slightly short with heavy furnace fan use.

cheryl

[DHart]

[QUOTE=ckottum;1604304]Unless the factory solar is all you need, primarily for lights, entertainment systems, and furnace and vent fans. It provides enough to recharge the factory AGM batteries by noon on sunny days. A generator runs the air conditioner and recharges the batteries on overcast days, and the propane system heats the trailer, hot water, and range/oven. The factory solar also keeps the batteries charged when the Airstream is not being used.

Our Airstream was on the lot with factory solar and inverter and we're glad to have it. It may not be for everybody for their own reasons, but is certainly a very usable system. The only upgrade we are considering is one size larger batteries when these wear out, the solar output is plenty but the battery storage is where we may come up slightly short with heavy furnace fan use.

Cheryl... I agree. If not planning to upgrade solar/inverter, I would definitely get the factory options for this... to cover basic needs!