Update on Inverter Operating A/C

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Dreamsend

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Got some real numbers from the manufacturer for the actual equipment in the Outdoors RV I'm likely getting.  Also, had them measure the tongue behind the LP tanks to get a handle on the feasibility of putting a generator and maybe a gasoline container in the spot.  Here is some updated info, and where I think I am now.

Equipment
A/C - draws 14.6 to 15.3 A when cooling, so that's about 15 A average.   
Fireplace - draws 11.7 A
Microwave - draws 11.25 A

All of the above of course at 120V.  Those are the big ticket items so far.

Converting ---
A/C about 1800 Watts.  Surge quoted at 2000 watts
Fireplace - 1440 watts
Microwave - 1350 watts

The trailer has 30 Amp service (3600 watts)

Generator
Honda EU20001 -- rated at 1600 watts running, 2000 surge, and 13 Amp draw, 1 gal fuel tank, no electric start
        Weighs 47 lbs.

Honda EU3000  - rated at 2800 watts running, 3000 surge,  and 23 Amp draw, 3.5 gal fuel tank and electric start
        Weighs 134 lbs.

(I'm using Honda as reference, cause I think most others, Champion, and the blue one etc. will be in the same capacity range for comparable models)

Comparing the A/C to the generators, it's obvious the Honda 2000i is too small.  The 3000i would be a good fit I'm thinking.  I also like the bigger fuel tank on the 30001.  Using 2 Honda 2000i gets me 3200 W, and the 3000i is 2800 W.  Yeah I could play around and burden myself with the idea of running JUST one 2000i, but given that you can throttle-down all the models, I'm not gonna be that picky with my operating scenarios.

Neither option looks like it will fit on the tongue behind the LP tanks, BUT, it's very close and I'm certain a carrier could be designed and welded to the frame that would extend the surface area enough to make this work safely and securely with a single 3000i.  I'd also like to be able to carry a gas can on the tongue, and NOT in the TT or the truck.  I'm not found of the idea of using a carrier mounted on the rear bumper of the TT -- rather have it up front.  But with the genny up front, I'll need longer extension cord because the hook-ups on the anticipated trailer are on the rear end! (not the sides).  So many things to think about #&*@#!

Being a haz material manager, I don't like gasoline!  I worry about things heating up in the HOT sun -- explosive vapors, even IF they claim gas cans are safe. 

Any helpful comments about carrying a ~ 3gal. gas can in the truck bed under a tonneau cover?  I'm sure many of you have experience with gas cans living full time in your pick-ups in HOT weather.

Also, a 1350 watt straight microwave without convection oven seems awfully big to me.  It's not a big deal, just curious.  Are microwaves in TT typically that big?

Best to all
Linda

 
Dreamsend said:
Also, a 1350 watt straight microwave without convection oven seems awfully big to me.  It's not a big deal, just curious.  Are microwaves in TT typically that big?

That's the microwave's power consumption, not it's heating power.

The Dometic RV microwave (CDMW10MW) in my RV is rated at 1000 watts, with 1500 watts power consumption and works really well.

At 1350 watts input power, you probably have an 800 watt microwave.

Dreamsend said:
Neither option looks like it will fit on the tongue behind the LP tanks, BUT, it's very close and I'm certain a carrier could be designed and welded to the frame that would extend the surface area enough to make this work safely and securely with a single 3000i.  I'd also like to be able to carry a gas can on the tongue, and NOT in the TT or the truck.  I'm not found of the idea of using a carrier mounted on the rear bumper of the TT -- rather have it up front.  But with the genny up front, I'll need longer extension cord because the hook-ups on the anticipated trailer are on the rear end! (not the sides).  So many things to think about #&*@#!

Where are your trailer batteries located?  The trailer tongue is a popular spot, if they're there, they may interfere with the generator mounting.

Make sure whatever you add to the tongue does not reduce the turning clearance between the trailer and the tow vehicle.
 
Hi Lou
Sorry to leave out the battery part.  I plan on lithium installed inside in a bunk area, so the normal tongue position for GC type will be freed up.  A suitable genny platform shouldn't interfere with any requirements between the truck, the hitch, and the trailer, but thanks for pointing it out - I'll add that to my planning notes.

And hey Tom, I have thought about a Class A -- almost longingly.  But decided on the truck and trailer option for the backcountry abilities and hopefully getting into more remote areas with the truck right now, not necessarily the trailer.  If the good Lord grants it, $$$ holds out, the economy is stable, no nuclear wars or asteroid hits for the next several years, I could absolutely see doing a used smallish Class A in my later silver-headed years and spending most of my time stationery as you are.  Other thing is, I'm not anywhere near being able to do all the maintenance and system fixes it appears the Class A-ers do - don't know anything mechanical. A Ford truck I can take just about anywhere for dealer service/repairs.  Linda
 
Are those generator weights dry weights. If you fill up the generator, {which you will}, and add a extra can as well, you will be adding several hundred pounds to your tongue weight. Make sure you dont overload the tongue weight on the hitch. Moving the batteries back will help for sure. I have never seen a factory generator on any travel trailer. I guess lots of them end up in trailer parks and dont need one.
 
I would lean toward not having the gas can near the genny. It certainly cant go near the exhaust end. If you have a bed cover it may be best to have a small TT bumper rack to store fuel.  I have older plastic fuel cans that would swell up like the doughboy when out in the sun so I open the vent a little. I know I know hydrocarbons.  With 3.x gallons in the Honda you may not need extra fuel on hand, just keep a 2 gallon empty can on hand in the truck bed. Fill the Honda at fuel stops and use the 2 gallon jug when going to town and not breaking camp so the can is always stored empty. If you are only running the Honda for the micro, toaster  etc occasionally vs hour after hour you will not use a lot of fuel. It's the ac and long charging hours that suck fuel.

Of course it costs more but it's very convenient to have a transfer switch where your shore power cord enters the rig and run 10 gauge up to the genny with a twist lock. Otherwise you have to drag a cord out a lot.  A transfer switch is simple to install and 10 gauge Romex can be fastened and protected along with the other mechanicals running under the rig. Before the romex exits the underside or perhaps in a storage compartment  run it into a junction box then continue outside to the genny with appropriate outdoor rubber covered cord. Price romex vs rubber cable for the whole run.  It doesn't happen often but it's nice to remote start the genny while driving and be cooled down when stopping for lunch or a short nap etc.

After the tongue mount idea your next option is an open truck bed with the genny bolted in. Of course the now longer rubber cord would then need to unplugged when you want to drive the truck away. The bad part is that stuff is out in the weather. Your next option could be to use a truck cap and mount the genny near the back and open the lid and drop the gate when running it with the exhaust pointed out the back though I dont like the idea of the exhaust pointed at the TT.

I dont remember the size but my old micro is sort of big. If I ever replace it I will go smaller since it's primarily for heating coffee water or defrosting.


Just some ideas:

Honda bolted in, two person operation to steal.
You do have to climb in bed to fuel.
Honda controls can be reached from side of truck.
generator is always with me for jump starts or tire filling.
Left side is clear for oil changes.
Cheap and highly effective 120 volt air compressor with rubber flap cover to keep it dry yet easy to uncover. Can reach from side of truck.
50' air hose reaches all the way back to the utility trailer.
No problem with fuel vapors.
10 gallons of fuel because I also have motorcycles.
Plastic tote carries oil, solvents, cleaners.
Long board on left is two pieces of 3/4 plywood screwed and glued together to form 10" x 1 1/2" x 5 ' long leveling board.
Bungees are also one of mans best friends.
I use an short aluminum ladder to get in bed because I'm old.

There is still enough room for 5 gallon water jugs. I also have a 60 gallon water bladder and two 15 gallon blue tanks that can go to town on a utility trailer instead of breaking camp. NO NO I never stay longer than 14 days ;) Promise.

Propane tank is empty but I chain/lock it down when traveling. I also secure the fuel jugs better.

I also wired in an Anderson connector to the genny battery in case it goes dead. It has happened if I leave the key on for too long without running it. The brain for the remote start uses power all the time.

I carry a Meanwell power supply which at times is used to equalize the rigs batteries or I can run it off the genny to jump my own truck or others with dead vehicle. I never connect jumper cables to my vehicle to start others.





 

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Lou Schneider said:
That's the microwave's power consumption, not it's heating power.

Lou and All - Hi

I see what you're getting at here, but can't seem to find any charts or info on making the conversion you suggest.  In thinking about it, every micro I've owned was sold as a particular rated wattage, i.e. 1000 watts, 1100 watts etc. They are still sold that way.  The appliances are marked with the plate showing that the stated watts is the power draw -- not a cooking power level.  If I have a 1000 watt micro, and need to cook something at 800 (watts), one is supposed to simply set the "power" level to 80% of the rated wattage for example.

Can you provide any reference for how you determined your conversion?  My bet is that the actual micro in the anticipated trailer is 1000 watts, not 1350.  But I'm not concerned, really just curious.

As to the generator issues, carrying gasoline etc.  I'm back to my initial inclinations of not worrying about powering an air-conditioner.  Outdoors RV sent pics of the available tongue area sans batteries and a platform that is available for that area (to place a battery box offered as a dealer add-on), and there is no way that a Honda 2000 or 3000 will fit there -- not even enough room to fabricate something larger.  Based on QZ's feedback, a closed truck bed does not look attractive for carrying a gen either.  But, a Honda 1000i is still an option for emergency use, as I can handle lifting and moving its weight.  I'm thinking like when needing power to get a slide closed, tongue jack up, awning in, or batteries charged to do so until I could break camp and get plugged in. 

Someone mentioned TT not having compartments for built-in generators, and I find that true also.  BUT, what started me down this merry lane was that Nash, made by Northwood Manufacturing in Oregon just came out with a bunk house model, the 29S, that does indeed have a built-in compartment for an Onan 3600 LP generator.  Nice!  Didn't look at other models so I don't know if they have added the genny option to other TTs.

So, I'm fine with going along with my initial thoughts of not having off-grid A/C, having an emergency gen, and enough solar and lithium to be able to adjust and anticipate conditions and head for shore power or cooler regions.  I'm sure I'll learn what's needed to work best.

Great feedback and information folks.  I really appreciate it.  Linda

 
Hi Linda ...

The input power and heating power of my microwave are stated on the nameplate label.  I took the ratio of 1300 watts (your oven's input power) divided by 1500 watts (my oven's input power) times 1000 watts (my oven's heating power) to estimate the heating power of your  microwave.  There shouldn't be much difference in efficiency between them because the basic operation of all microwave ovens are the same.

A generator compartment needs venting to dissipate gas fumes and fire resistant walls so if a fire should break out you have a chance of fighting it or at least getting out of the RV before it spreads.  This is part of what manufacturers offer with a generator ready package.
 
I have been cooking with a microwave since the 70s. Always with a 600 watt job. Six months ago I bought a new RV with a dead microwave so I replaced it with a 1200 watt job. I just cut the cooking times in half and then feel how warm it is. If it is not hot enough I give it a few more seconds. The simple way is to not ever over cook anything. You can always pop it back in for a few more seconds.
 
Microwaves are advertised by their output cooking power, e.g. 1000 watts. That is NOT their input power, which is shown on the UL rating plate on the back. For a modern microwave, the input power draw is typically 40-50% greater than the advertised cooking power.

Both numbers are valid, but you want to be careful about which one you use for each purpose.
 
I just looked mine up. The cooking power is 1250 watts, the input is 1500 watts. The good news is it is selling for $30 more than what I paid six months ago.

Interesting story. I needed some help with three projects so I asked my nephew to drop by. My recliner leaned to the right and was causing me problems. He suggested he could cut some pieces of plywood to shim one side. He just looked at it and guessed at the dimensions, then went home and cut two 1/2" pieces of plywood. He brought them back and put one under the base and it was perfectly level. So we moved on to the second problem. The microwave was a counter top job and not meant to be installed in a cabinet cut out. So every time I pushed the start button the microwave would push back into the hole and the door was harder to operate. Every day I had to pull the microwave back to flush. It needed a board behind it so it would not move. He pulled the microwave out and I measured and we both said let's try the other board first. Absolutely a perfect fit. We could not have gotten it better if we would have measured and attempted to cut the perfect size board. Both edges of the microwave are flush as can be and it doesn't walk back into the hole anymore.
 
The cooking power is 1250 watts, the input is 1500 watts.

Great efficiency for a magnetron - they've really improved a lot. The 1986 vintage GE in our kitchen at home draws a whopping 1250 watts to produce just 700 watts of cooking power.
 
I too was shocked, Gary. It is a great microwave. Cooks everything real fast. Here is a link in case anyone is interested:

https://www.amazon.com/gp/product/B00FRD0PNC/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
 
Lithium is a great battery but you will need to update your converters on board charger to take advantage of them.  My ORV AC will start and run very well on one Honda 2000 which you could just carry in the bed of the truck.  My ORV also came with a hitch receiver on the rear bumper which you can mount a platform to and carry it there as long as it is chained down well. That would be my choice.  If you are not going to place the batteries on the tongue there would also be plenty of room for the genny to be placed on a platform there as well. Any welding shop can make a custom one for not much money. If you will not have batteries there that may be a better way to go so you keep the tongue weight high enough.
 
Keymastr makes a very good point, make sure you still have enough tongue weight if you eliminate the heavy lead-acid batteries from the tongue, especially if you also add weight to the rear of the trailer.  As you lighten the tongue the trailer's center of gravity moves rearward.  Move it too far back and the trailer becomes very unstable. 

There are numerous videos on YouTube showing what happens when the tongue gets too light.  Here's one:

Safe Trailering Demonstrator
 
Lithium batteries require very different charging systems than lead acid cells. If you just swap out the batteries I would worry about fires and maybe something worse (remember the Galaxy 7 Note)!
 
Dreamsend, you've probably solved your riddle, but I might have one other thought. Northern tool (I think. Been there for three years, I just pull the rope a couple times) sells a 3750? watt propane gen through Home depot, and others, that weighs about a 100lbs. I built a carrier for it, and a bin, on the rear of my 26' TT, plumbed it into the water heater line, and went to two 7gal tanks and two Trojans. The bolts holding it are peened over the nuts. Theft proof, no gas, and no turning issues. Not 'Honda quiet', more like Champion, but will run the the a/c all night and day without putting gas in. Been on the TT for about 14k mis. My 2ct.
 
I think the Lithium batteries sold as direct replacements for lead-acid 12v's are probably reasonably compatible with standard 12v charging systems. Brands like Smart Battery have a built-in BMS that handles the charging prperly. Greenlife Lithiums also have that.

https://www.lithiumion-batteries.com/

https://www.amazon.com/GreenLiFE-Battery-GL100-100AH-Lithium/dp/B01NAV9G9X

Beware of lower priced lithiums that may not be "plug & play" replacements for a lead acid battery - they may not have the necessary battery management as part of the battery. That saves on the cost but risks the damage or fires that others have referenced.
 

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