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How do I calculate the inverter / batteries / Solar panel thingy?


MoonTimber

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After being away from travel trailers for nine years, my wife and I just purchased and old 1991 Jamboree Rallye. We're planning on taking our two little kids on weekend boondocking trips once a month and then doing a two and a half week there and back across the country late in the fall.

 

The Rallye does not have an inverter or solar panels. It has a well maintained generator with one dedicated battery to handle all the internal lights and electrical appliances.

 

My wife makes her living doing online sales and blogging, and I am occasionally required to login remotely to do tech support and software fixes so I need to make sure that we have enough off the grid power for two power hungry laptops (140 watts each), cell phones, and a multifunction printer/scanner.

 

In a pinch we should be able to hook up the onboard generator to get power. But in general I want to have a solar power system that is pretty much independant of the RV to power two laptops, three cell phones, four 7" android tablets, four hours a day (The tablets use about as much power as a phone). I'm guessing a 2500 watt inverter will be more than enough power for all of this, but how many batteries and solar panels do I need? Since we're not going to do this full time, I'm looking at very inexpensive 100 watt solar panels on Amazon. I will pack them inside the RV between trips. I have several unused 12V 2ah UPS batteries I can borrow for each trip but I have no problem buying a bunch of golf cart or car batteries.

 

 

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http://www.rv-dreams.com/rv-electrical.html is a good overview of RV electric in general, along with batteries and solar once the basics are covered. Howard provide links to many of the webpages others will reference, including Jack Mayer's http://www.jackdanmayer.com/rv_electrical_and_solar.htm#Introduction%20to%20Solar.

 

Everything matters to have a good experience, being cheap on panels, charge controller, charger and especially wiring will hurt your ability to keep things working. Do your homework.

 

I am going out on a limb, but my gut says at least 400 watts of solar with the option for 600, 4 golf cart batteries miniimum, a 2000 watt or larger pure sinewave inverter/charger (don't go modified with sensitive electronics), at least a 30 AMP MPPT charge controller, and go big on wire sizes. Once you add up what this will cost, you might find that running a small generator will be a better idea.

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Your rooftop size is going to determine a lot of this. In our little 21' 1970s Streamlline (which is similar to an airstream) I couldn't put any solar on it unless it was leaning against the TT somewhere. But in our 36' DP I have enough room to get 600 watts easy. The big fifth wheel trailers can put over a kilowatt up there.

 

Kirk's estimate of 400 watts is probably not unreasonable. But *any* solar would be a start. The panels are one of the cheapest aspects of the system, actually. The 12vdc (nominal) panels are more expensive - on a per-watt basis - than the 24vdc (nominal) panels but they are also smaller and can fit onto roofs easier. The 24vdc panels are more common for houses and buildings so they are producing more fo them.

 

Get a good controller right off the bat... MPPT and at least 30-amp (as Kirk mentioned). Make sure you have a decent battery bank. There is no advantage to having a 1,000 watts of solar if you have only one deep-cycle battery. Most of us shoot for a system that has the battery bank fully charged by noon or a little after on a reasonably sunny day. If it never charges fully then you light up the generator (and add another panel when you can). If it charges early than you can plug more stuff in. :P

 

You could go through an "audit" and figure out exactly (more-or-less) what you'll use and then match that. But... I dunno.... that seems like a lot of work to me.....

 

Just remember that you can add panels; panels in parallel (the most common configuration - but maybe not the best) need to have their current output matched pretty closely and panels in series (which has issues of its own) have to have the voltage output match closely. In both cases, the smallest one determines the output and may even be damaged if out of spec too badly.

 

There is some talk that an MPPT solar charger controller should really have 24vdc (nominal - it's really more like 36vdc from the panel) input from the solar array for a 12vdc system. So you could buy one 240-watt panel (if it fits) and try that. If it's not enough, install another one. Two panels would be 480-watts and that should do pretty well; although you may still need the generator on a cloudy morning after working late.

 

2000 watts of inverter will run a lot of stuff... not your air conditioner but still, a lot of stuff. Install it as close to the battery bank as you can. I like to have smaller pure sine wave inverters around the coach and one 1500-watt inverter just above the battery bank. I've found that the LED TV and the BluRay player can both run on less than 150-watts which can be supplied by a cigarette lighter plug. So an $80 PSW inverter that can plug into a 12vdc cigarette lighter plug is close to my TV and BluRay just for those two. No special wiring. Some people use one 400-watt PSW inverter for their residential refrigerator and leave that on all the time. Smaller wiring and also smaller idle current (amps drawn from the battery bank when nothing is demanding power).

 

There are some rules (wire size, power draw, voltages) but a lot of this is personal preference. You can even buy a charge controller and a panel and just lean the panel up next to the RV (facing the sun is best) and connect it up to see how it works. I've camped with panels leaning against my trailer tongue; and able to move them to keep facing the sun is good, too.

 

WDR

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I don't have time now but later will run some calculations for you HOWEVER just as a pure GUESS NO WARRANTY I will venture this:

 

At a MINIMUM Id want 200 Watts of Solar and two 6 volt true deep cycle golf cart batteries in series, that's around 205 to 230 Amp Hrs of energy storage capacity depending on batteries used.

 

Id feel much more comfy with 300 to 400 Solar Watts and four 6 volt true deep cycle golf cart batteries, that's around 410 to 460 Amp Hours of energy storage capacity.

 

NOTICE BEFORE ANYONE HAS A CALF.....The ACTUAL figures depend on hours of use,,,,,,loads,,,,,,,,angle of sun and how many hours of sunlight,,,,,,,solar capacity,,,,,,batteries etc etc etc. so its IMPOSSIBLE TO SAY FOR SURE UNTIL CALCULATIONS ARE PERFORMED.

 

I Would use a SMART 3/4 stage quality MPPT Solar charge Controller

 

You mentioned 140 watt laptops for four hours per day, if I had the cell phone charger watts and time along with the tablet wattage and time etc. I could perform more exact calculations. Any guesses (like mine above) NOT having the actual loads and time of use are purely GUESSES SO BE FOREWARNED. It also depends on sunlight hours and intensity and angle etc which can be difficult to know and subject to weather but it never hurts to figure conservative lol

 

John T Long retired Electrical Engineer so NO WARRANTY

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If you would like to conduct an energy audit, here's our post going over one such approach (ours is a bit tedious.. and did take quite a bit of time.. but we know what everything in our coach consumes):

 

Solar Planning: Conducting An RV Electrical Consumption Audit

 

Since you're not going full time.. you'll want to consider where and when you'll be going - as length of day, temperature, tilt angle, etc. will all play into the amount of energy you'll be able to collect on a given day.

 

- Cherie

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One thing is 140 watts for a laptop is a little heavy. That is probably the max when your battery is dead and is charging. One of the first steps, using a Kil-o-watt meter to get a more real set of numbers. That has to be the first step. My laptop PS is 2A at 125 vac -- 250 watts. Meter shows 55 watts running and 5.4 watts in sleep.

 

Older one, 17" screen (NOT LED, fluorescent backlight, LCD), dual hard drives, 16 GB memory, etc. Just saying

 

Then, from that, I would size the inverter / battery combo.

 

Also, look at lighting and other loads. LED lights use 10% or less than incandescent lights. Energy saved is energy that doesn't have to be made or stored.

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What awesome responses! it's going to take me a few hours just to get through the links, but it sounds like my first step is finding a meter to figure out what our laptops actually draw. Is that something I can find at my local home depot? What exactly is it called?

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What awesome responses! it's going to take me a few hours just to get through the links, but it sounds like my first step is finding a meter to figure out what our laptops actually draw. Is that something I can find at my local home depot? What exactly is it called?

 

Kill-A-Watt meter.

 

One thing you might consider is purchasing 12v cords for your laptops, printer, etc. It's not terribly efficient converting DC (battery bank) to AC (inverter w/overhead) then back to DC again (laptop cord).

 

One additional strategy that might prove helpful... once you are on solar.. is to be aware of "when" you are recharging. If your solar array is sufficient to fully recharge your battery bank on a daily basis, you 'may' have surplus energy production before the sun goes down. It is ideal to use that surplus production time to recharge your devices or perform other more energy intensive tasks.

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Its a new day and I have more time now, last night we were at an Antique Tractor Show in Zolfo Springs Florida and went to see Goldwing Express, awesome performance.

 

INVERTER:

 

You mentioned a couple laptops at 140 watts plus a couple tablets plus maybe some cell phone chargers and perhaps a TV etc.???? That being said a typical size of 400 Watt Inverter would be close to marginal so Id suggest a 1000 Watt MINUMUM and I also suggest use of a PURE SINE WAVE INVERTER. However if you want to allow capacity for expansion then a 2000 Watt may be in order.

 

Of course, if you want to go the Cadillac Route and also need to install or upgrade a Converter/Charger to a so called SMART 4 stage technology charger, you may consider a combination Inverter/Charger unit.

 

ENERGY & BATTERY ENERGY STORAGE CAPACITY

 

You mentioned a couple laptops of 140 watts operating at 4 hours and a couple tablets plus phone chargers etc. The tablets and phone chargers don't take the energy a laptop does but to be over safe and conservative let me throw out a pure OVER guess of say 250 watts operating for four hours. AGAIN THATS A PURE "OVER" GUESS.

 

If you used 250 watts for four hours a day, that's 1000 watt hours the Inverter is drawing out of your batteries. At 12 battery volts that's 1000/12 = 83 amp hours per day of energy your battery bank would have to supply. NOTE inverter efficiency and exact voltages have NOT been used, this is ONLY a rough estimate!!!! Okay if you had two typical true deep cycle 6 volt series golf cart batteries with an energy storage capacity of 205 amp hours, they could handle the 83 amp hours of use which is what I guessed above would be the MINIMUM Id recommend.

 

SOLAR CHARGING to replace and replenish those 83 daily amp hours if your solar system could deliver lets say 10 amps for 8.3 hours that would suffice. Now, if you had 200 watts of solar panels "around" (depends on sun and intensity and angle and duration etc etc) 15 amps is "around" the maximum and if they delivered 10 amps you would be hard pressed to get that for 8.3 hours SO A 200 WATT SYSTEM WOULD BE MARGINAL if you actually needed to capture 83 amp hours per day AGAIN IT DEPENDS ON SUN AND INTENSITY AND ANGLE AND TIME

 

SUMMARY AND PURE SPECULATIVE GUESS (so no freaking warranty)

 

Based on the limited info you provided and subject to sun and angle and intensity and time, I' m back close to my original rough estimate I WOULD WANT 200 WATTS MINUMUM OF SOLAR PANELS BUT PREFER 400 WATTS,,,,,,,,,,,,WHILE YOU MAY "GET BY" WITH TWO GOLF CART BATTERIES, ID PREFER FOUR WITH A TOAL CAPACITY OF 410 + AMP HOURS,,,,,,,,,,,,A 1000 WATT INVERTER CAN GET YOU BY, BUT A 2000 WATT ALLOWS ROOM FOR EXPANSION,,,,,,,,,,,,I PREFER PURE SINE WAVE AND YOU MAY CONSIDER A COMBINATION INVERTER/CHARGER.

 

So there's a pure GUESS but the ONLY way to answer your question is to know all the total loads and times etc and given all that its an easy engineering calculation, but short of that its ONLY A PURE GUESS ON ANYONES PART. Go do your homework and research and post back any questions.....

 

John T

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Its a new day and I have more time now, last night we were at an Antique Tractor Show in Zolfo Springs Florida and went to see Goldwing Express, awesome performance.

 

INVERTER:

 

You mentioned a couple laptops at 140 watts plus a couple tablets plus maybe some cell phone chargers and perhaps a TV etc.???? That being said a typical size of 400 Watt Inverter would be close to marginal so Id suggest a 1000 Watt MINUMUM and I also suggest use of a PURE SINE WAVE INVERTER. However if you want to allow capacity for expansion then a 2000 Watt may be in order.

 

Of course, if you want to go the Cadillac Route and also need to install or upgrade a Converter/Charger to a so called SMART 4 stage technology charger, you may consider a combination Inverter/Charger unit.

 

ENERGY & BATTERY ENERGY STORAGE CAPACITY

 

You mentioned a couple laptops of 140 watts operating at 4 hours and a couple tablets plus phone chargers etc. The tablets and phone chargers don't take the energy a laptop does but to be over safe and conservative let me throw out a pure OVER guess of say 250 watts operating for four hours. AGAIN THATS A PURE "OVER" GUESS.

 

If you used 250 watts for four hours a day, that's 1000 watt hours the Inverter is drawing out of your batteries. At 12 battery volts that's 1000/12 = 83 amp hours per day of energy your battery bank would have to supply. NOTE inverter efficiency and exact voltages have NOT been used, this is ONLY a rough estimate!!!! Okay if you had two typical true deep cycle 6 volt series golf cart batteries with an energy storage capacity of 205 amp hours, they could handle the 83 amp hours of use which is what I guessed above would be the MINIMUM Id recommend.

 

SOLAR CHARGING to replace and replenish those 83 daily amp hours if your solar system could deliver lets say 10 amps for 8.3 hours that would suffice. Now, if you had 200 watts of solar panels "around" (depends on sun and intensity and angle and duration etc etc) 15 amps is "around" the maximum and if they delivered 10 amps you would be hard pressed to get that for 8.3 hours SO A 200 WATT SYSTEM WOULD BE MARGINAL if you actually needed to capture 83 amp hours per day AGAIN IT DEPENDS ON SUN AND INTENSITY AND ANGLE AND TIME

 

SUMMARY AND PURE SPECULATIVE GUESS (so no freaking warranty)

 

Based on the limited info you provided and subject to sun and angle and intensity and time, I' m back close to my original rough estimate I WOULD WANT 200 WATTS MINUMUM OF SOLAR PANELS BUT PREFER 400 WATTS,,,,,,,,,,,,WHILE YOU MAY "GET BY" WITH TWO GOLF CART BATTERIES, ID PREFER FOUR WITH A TOAL CAPACITY OF 410 + AMP HOURS,,,,,,,,,,,,A 1000 WATT INVERTER CAN GET YOU BY, BUT A 2000 WATT ALLOWS ROOM FOR EXPANSION,,,,,,,,,,,,I PREFER PURE SINE WAVE AND YOU MAY CONSIDER A COMBINATION INVERTER/CHARGER.

 

So there's a pure GUESS but the ONLY way to answer your question is to know all the total loads and times etc and given all that its an easy engineering calculation, but short of that its ONLY A PURE GUESS ON ANYONES PART. Go do your homework and research and post back any questions.....

 

John T

 

 

I think this kinda answers my question. I started reading some of the links, which require a lot of data collecting and planning, but the example I gave of two laptops, four tablets, etc., is really just a "worse case scenario". I think most of the time our gear is going to be on a shelf turned off. My wife can get her work done in about two hours on most days, and can probably do half of that on a tablet. If we need to put in a long work day I can either run the generator or pack up and head to a campground with full hookups and wireless. I think most of the time we'll be able to get by using the tablets (which don't use up a lot of power.) It sounds to me like I need more batteries than panels. My RV has one car battery connected to the built in generator. I think what I want to do is get the inexpensive Renogy 100W mono solar kit on Amazon (it's only $170). It includes the 30W controller. Then I'll pick up the 2500W inverter I was looking at which should handle our laptops and give me lots of room for future expansion. Then I'll track down two batteries. I'll also order the 12V adapter for our laptops. This should cover our needs 90% of the time since typically we are going to do short trips, and I just need to make sure the batteries are full before leaving home. If we start doing longer trips on a regular basis I'll have to add panels and probably another pair of batteries, but for now I think this will do the trick.

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One thing I want to confirm with you is the type of inverter you are thinking of getting. It should be PSW not MSW. The reason I ask is because a 2500W inverter is WAY oversized for your needs and you have to remember that the inverter also consumes energy. A quality 2500 inverter is expensive so make sure you are buying the quality you need for electronics. You can get away with lower quality inverters for some things but powering electronics requires pure sine wave. There is nothing wrong with buying a smaller, efficient psw converter.That is the way I would go in your situation. Some prefer to run a few smaller inverters rather than one large one so it is not necessarily money lost if you later expand your system..

 

Also, you mention a car battery. When you buy new batteries be sure to get deep cycle. Probabaly the best lower price option is to get two or 4 6 volt golf cart batteries from Costco or Sam's.

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Good advice all.

 

Remember you have other things in the RV to power as well, such as lights, water pump, slide motors (short duration but high amp draw), refrigerator electronics (low amp but long duration), etc.

 

Considering these other items, I'd go with a least 2 - 6v golf cart batteries, a 1,500 watt PSW inverter, for tvs, kitchen appliances, etc. (2,000 watts if you want to run your microwave.) Smaller inverters are more efficient. Add a cheap 200 watt accessory (cigarette lighter) plug inverter for phone and tablet charging and you'll be set.

 

Frankly, it's not worth the trouble of adding solar for only 100 watts. With 100 watts of solar it will take you two full sunny days to charge your 2 golf cart batteries only 50%- assuming you are not drawing any power from your batteries while it is charging. You will find it insufficient for your needs and not be a happy camper. 200 watts will be marginal, but you'll be happy with 400 watts (as will your family, as you will not be hollering at them all the time not to use anything.) ;) If it were me and I had the choice between 2 GC-2 batteries and 400 watts of solar, or 4 batteries and 200 watts of solar (close to the same cost) I'd get the 400 watts of solar.

 

Sam's GC-2s are about $84 each where I live. Here's a Sharp 245 watt (24v) module ($0.71/watt.) for $172 (MPPT controller required). http://sunelec.com/solar-panels/24v-solar-panels/sharp-245w-module.html

 

Chip

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Smaller inverters are more efficient.

 

 

That may not necessarily always be true. It's important to take into account the overall efficiency of the inverter as well as the connection types... not just the printed "overhead" wattage. Some of the nicer (aka expensive) inverters are also programmable which helps to reduce overhead for an intended use, as well as maintaining higher levels of efficiency. A gross example.. but you're not going to see much in power savings going from say.. a $200 600watt hardwired Samlex to a $50 wallyworld 200watt plug in. More than likely all you will see is a 400watt deficit in available current for about the same power consumption from your battery bank.

 

Just sayin... :D

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Moon Timber, you say

 

" I think what I want to do is get the inexpensive Renogy 100W mono solar kit on Amazon (it's only $170). It includes the 30W controller. Then I'll pick up the 2500W inverter I was looking at which should handle our laptops and give me lots of room for future expansion. Then I'll track down two batteries. I'll also order the 12V adapter for our laptops. This should cover our needs 90% of the time since typically we are going to do short trips, and I just need to make sure the batteries are full before leaving home."

 

SOUNDS LIKE YOURE GETTING MORE REALISTIC NOW, few comments:

 

Based on your use, sure a 2500 watt inverter will work, but based on your loads and solar and batteries, it may be slight overkill (but hey I'm conservative and that don't bother me lol) Id say a 1000 watt PURE SINE WAVE is a close to match to the rest of your proposed installation, but the 2000 allows room for expansion....

 

For the two batteries you mention, Id opt for two true 6 volt deep cycle golf cart batteries (around 205 to 230 Amp Hrs each) wired in series NOT two semi deep cycle so called RV/Marine batteries.

 

YES 12 VDC direct beats the inefficiencies and heat generated by a 12 VDC to 120 VAC Inverter......

 

FWIW and perspective,,,,,,,,I'm currently running 200 watts of solar, four 6 volt batteries (460 Amp Hrs) and my loads are occasional water pump, vent fans, LED lights, small TV, Laptop, Kindle, cell phones, and I can keep up just fine HOWEVER I added a small 120 VAC dorm fridge I power via a 1000 watt PSW Inverter and if it's rainy and cloudy a few days in a row its getting marginal, so I'm adding another 200 or 240 watts of solar next spring....

 

Keep on keepin on

 

John T

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The inverter I was looking at is the Cobra CPI 2575 2500 Watt 12 Volt DC to 120 Volt AC Power Inverter on Amazon for $189. I have a very old 400W inverter that I can take along but I was hoping to just set up one inverter. If there is a better inverter I should use in that price range I'm open to suggestions. I know it's way more than I need for two laptops, but I want it to migrate with me if I decide later on to run a television or a microwave oven.

 

My RV has one regular 12V battery, and 1 Deep cell battery in it. Both are pretty new. I can do golf cart batteries, but since there is already a 12V deep cell wouldn't it make sense to match it? Does it matter?

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Moon Timber that is a modified sinewave inverter. Almost everyone here will recommend pure sine wave for an intverter. Although modified sine wav inverters invert to the correct voltage they emit a wave form which differs from that which you will get from your home ac outlet. This can cause problems with some electrical equipment.Generally, the more sophisticated the electrical equipment you intend to power the greater the potential for problems. Since you specifically intend to use your inverter to power computer equipment the concern would be the cobra would not allow your equipemnt to function correctly and/or shorten the equipment life. For that reason those on this board above recommended a pure sine wave inverter. Here is a link to the xantrex web site where they discuss modified vs. pure sine wave. http://www.xantrex.com/documents/tech-doctor/universal/tech1-universal.pdf%C2'> Without looking over other options etc,, I notice that on the Amazon page one of the alternatives availalbe was a zamp 600 watt psw inverter for a similar price..

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Just to confirm, the starter battery and deep cycle are separate? They should not be combined. Generally your batteries should be identical or as close as possible. Pairing your exisitng deep cycle to one just like it would work but be aware the new one will most likely degrade down to match the old one.

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"My RV has one regular 12V battery, and 1 Deep cell battery in it. Both are pretty new. I can do golf cart batteries, but since there is already a 12V deep cell wouldn't it make sense to match it? Does it matter?"

 

Your existing 12 v deep cell... Is it a semi or quasi deep cycle such as the ones sold at Wally World and elsewhere and labeled as an RV/Marine Battery???? If so, that's NOT the same as a true deep cycle golf cart type of battery. SURE it will "work" if you match it with another one, HOWEVER its best of two batteries tied together are the same type and size and design and age etc., so the weaker one doesn't cannibalize the stronger, but its your money to do with as you please. NOTE Trojan and other companies do indeed make 12 volt true deep cycle batteries, but they are fairly rare and are NOT the same as RV/Marine so called deep cycle batteries. I have used 2 or 3 quasi deep cycle RV/Marine 12 volt batteries in parallel but NEVER got as good service for deep draw down RV use as I get from my deep cycle 6 volt golf cart batteries.

 

My 1000 Watt Pure Sine Wave Inverter works great and I got it for a bit over $100

 

I don't want to scare you, money doesn't grow on trees and you can "get by" with less then I recommend, but I'm just offering my professional old retired engineers opinion. Some on here may have a 40 or 50 ft motorhome and 500 to 1000 solar watts, 3000 or 4000 watt Inverters and/or Magnadyne Inverter/Chargers and that's fine, but it doesn't sound like you (or I) need all that.

 

Best wishes

 

John T

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Actually, the elephant in the room is the existing generator and the old converter.

 

I would bring the batteries up to par (matched set as above), a good 3/4 stage charger (progressive Dynamics - PD9280) and your inverter (as Above)

 

Chances are the old MH came with an old charger. You get up, fire off the genny, make your coffee / breakfast (and charge the batteries auto). Do your whatever, fire it up for supper. I would get a battery monitor to use the batteries between 40 (50 is better) % and 90%. You can ad the solar portion at a later date. Maximize what you have (generator), The batteries and the rest of the improvements will still be usable with the solar.

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I researched inverters about 20 years ago and forgot everything. Thanks to the comments here I'm reasearching it all over again. I'm pretty fuzzy on some of the logic on this so please bear with me.

 

I haven't gone RVing in many years, but when I did I used various laptops for several days in a row on my 400W modified inverter and never had any trouble. The laptops use transformers - they convert the AC to DC, so that as far as the laptop is concerned there is no sine wave at all. It's all 12vdc, 5vdc, and sometimes 3vdc internally. Where I get fuzzy is on the transformer. I'm under the impression that a transformer is a very simple circuit which by design would ignore noisy incoming AC. The transformer should take any pulse and flatten it. My old Lenovo transformer actually had noise suppresion built in. My little LED television also has a transformer built into the casing and all of my tablets have transformers to charge with. I think if I were trying to run a variable speed power drill or a blender it would either act like it was drunk or fry itself pretty quick, but I'm confused as to why a laptop should have trouble transforming the modified sine wave to DC.

 

Remember, we're not planning to live in our RV. We just want the flexibility of boondocking from time to time without constantly running a generator. What I mean is we probably won't be hooking up quite so many luxuries - like a blender or electric griddle. Our fridge and cooking will be powered by propane. For our scenario I'm not sure I understand why the PSW inverter is so important. Do we have any electrical experts in the house who can set me straight?

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Moon guy, Im in a hurry getting ready to change RV park so I will give you a start and check back this evening.....

 

A transformer DOES NOT change the waverform, its still garbage in = garbage out so if you insert a MSW you still get an MSW out. Sure you can use some LC filtering circuits and chokes to suppress input spikes and transients but you still get a MSW out.

 

The better filtering to produce 12 or 5 or 3 VDC for a computer comes by using filters and chokes to smooth out the DC ripple from the rectifier circuit for a good level smooth DC output for your electronic device.

 

YES I have also used MSW to power electronics and never had a problem and you may never do so HOWEVER just because it works does NOT mean its best or recommended.

 

Maybe later I will talk about PSW versus MSW for some devices but no time now. Remember a MSW is like a series of ladder steps and small square waves which does not transform as efficient as a pure wave.

 

All I can say is I used to use MSW but now I have 2 Inverters BOTH of which are PSW and theyre not all that much more expensive.

 

Your money your equipment your choice, MSW will work and likely never cause a problem but I can imagine more heat losses and current loops taking place in motor magnetizing circuits such as in a fridge compressor where PSW works best.

 

I will be back this evening, heading out now

 

John T Long retired EE so no warranty, Im rusty on this stuff

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