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geO

Operating the solar questions

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Never owning a RV I'm needing to better understand the do's and don'ts of using solar. Can I run everything except the a/c and microwave? I understand the refrigerator has a heavy drawl on the batteries so best mode is probably auto?

 

When should I turn on the power inverter and what are it's limitations?

 

Thank you

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The inverter is used for the microwave and any 110 outlets. It will not run the air conditioner. That's the end of my knowledge :-)

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Yvonne & Doug


2017 Legacy Elite II, twin bed


Hull #223


2017 Ford F-250 Lariat, crew cab

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geO,

 

All the inverter does is convert 12 volts to 110 volts.  Depending on the size of the inverter one can operate virtually any electric appliance up to the inverter's capacity.  Assuming that you have the standard 2000 watt inverter that Oliver typically sells with its campers, you could theoretically operate any 110 volt electric appliance up to 2000 watts.  However, there is some loss in the conversion from the 12 volts to the 110 volts (and a couple other technical things), thus it is best to not try operating anything above about 1500 watts.  This 1500 watts includes most hair dryers, toaster ovens, coffee pots, TV's, radios, computers, microwaves, etc.  Simply look on the appliance you want to use to see how many watts are listed - if it is below 1500 you are good to go.  If it is above 1500 watts or if you can not find the watts on the appliance then it would be better to not use it.  Also, don't forget to add up those watts if you are trying to operate more than one appliance at a time - you still should not go over the total of 1500 watts.

 

Mind you that this is a simple explanation and not all inverters are as good as the one in the Oliver.  So, do not use this as a blanket statement for all inverters.

 

Hope this helps!

 

Bill

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2017 Ford F150 Lariat 3.5EB FX4 Max Towing 2016 Oliver Elite II - Hull #117 "Twist"

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Bill, thank you for taking the time to teach me a few things about the inverter. I just did not want to make a huge mistake and blow something up. 1500 watt max is a point well taken. I have so much to learn about power management and the other systems as well.

 

george

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George,

 

While on battery power just use the 120 volts from the inverter sparingly and watch the battery voltage to keep an eye on it. You'll probably just run the microwave a for a minute or two to warm something up now and then. When you are done with the inverter, like after breakfast for instance, shut it off.

 

It doesn't make any difference wether you are "on solar" or not as to what you run on the inverter, or at least not enough to worry about. Consider the solar to be a battery charger. The batteries carry the heavy demand of the inverter and do it regardless of the sun. You might hold off on running the microwave until the solar has had all day to catch up, but what if you want the microwave for breakfast duty? Like in your car, you fill the tank at one time and you drive it at another time. The batteries are the gas tank. Just monitor the charge level of the batteries and consider all the ways to keep them charged. It would be nice if you could live within the power from the solar, but don't count on it with all of the variables of power usage, weather and shading.

 

We have a small, cigarette lighter style inverter that we use to charge phones and computers. These are cheap and easily available at auto parts stores or camping supply stores. They work really well in the tow vehicle too, while underway.

 

To check Ollie's batteries, let them rest for a while after a load and then check their voltage. You probably should not run them down below 12.3 when rested. Checking them while using them does not give an accurate reading.

 

You can preserve a lot of power by heating water on the stove instead of in the microwave, for instance. Run the fridge on propane unless you are plugged in. Don't try to run the heat strip, electric heater, electric coffee maker or other 120 volt appliances from the inverter. Just short term loads like a minute or two in the microwave, or run a power tool.

 

We have the T105 batteries and I'm pretty careless with my 12 volt consumption. LED lights in the Ollie are very efficient, so we leave the courtesy lights on all night. We watch movies in the evening and we charge the computers/phones whenever we want with the small cigarette lighter inverter. Then if we get low after a couple of days, I run the 2000 watt generator for an hour or so. It's a perfect match for the on-board charger.

 

So, try not to let the rested voltage go below 12.3. You will see 12.3 while the batteries are under load, and that is OK. Charge with the generator plugged in until you see 14.2. Rested full charge is about 12.65. That means they were brought up to 14.2 and then removed from the charger and rested. When plugged in, the batteries will come up to 14.2 and then go to a "float" charge that will carry loads and protect the batteries from overcharging. That will be 13.2 or 13.5. With a glance at the battery monitor you can tell just what is going on. If you have solar and are parked in the sun, you will see the voltage climb during the day if you are not taking more out than the sun is putting in.

 

A rough guide is to look at the batteries you got in your Ollie and figure out how many amp/hours they are. For example, if they are 300 amp hours total, you could draw 1 amp for 300 hours, or 10 amps for 30 hours. But since you don't want to draw them down below 50%, cut those numbers in half. And the faster yo draw it out the less you get overall.

 

If you wanted 1200 watts at 120 volts from the inverter, an approximate microwave load, you would be pulling about 11 times the amperage from the batteries as you are delivering at 120 volts to an appliance. 1200 watts at 120 volts is 10 amps at 120 volts. Eleven times that, at the battery, would be 110 amps. So you can see that if you could only draw 50% of 300 total amp hours from your batteries you only have 150 available. One hour on the microwave would be all they could do. Especially since you get less total amps, the faster you draw them.

 

You probably won't run the microwave for an hour, but think about an electric heater that you might want on all night. No way it will work. Or you might run the microwave for 15 minutes, an electric coffee maker for 15 minutes, a hair dryer for 15 minutes and an electric heater for 15 minutes and the batteries are at the 50% mark or lower. Done, until you re-charge. So use the inverter sparingly until you get the feel of it.

 

Some typical 120 volt loads might be:

 

Microwave 1000-1400 watts. I think Ollie's have 1400 watt units

Electric heater 750 watts on low and 1500 on high

Hair dryer approx. 1200-1500 watts

electric coffee maker approx. 1200 watts

Computer and phone chargers are very small loads of about 50 watts or so. Not sure just what mine are, but we can charge a phone and the computer for less than 100 watts.

 

All of those 120 volt loads pull 11 times the amps on 12 volts from the batteries. A 10 amp 120 volt load (1200 watts) takes about 11 times as many amps from the battery at 12 volts, or 110 amps. If your batteries were 220 amp hour rated, they would be at or below 50% in one hour. But since that is a heavy load, they would probably be done in about 45 minutes. You can look up battery load charts and see the relationship of load and time.

 

So, the bottom line is: just be careful until you get the hang of it. leave the inverter off until you want to use it. Use propane for the fridge and heat. Watch your battery monitor and think about what it is telling you. Don't run the batteries down below 50% or so which is about 12.3 volts rested. Since the solar won't work at night and you probably don't want to run the genny at night, head into the evening with enough charge to run the lights, watch a movie and charge your computer or phone, until morning. You might even settle into a routine where you run the genny, if the solar was poor that day, in the evening to pop the voltage up to 14.2 while making dinner and using the microwave a bit. Then you will have plenty for the night to run the heating fan with propane heat, run the lights, etc. If you are at 12.4 and all you want to do is a bit of reading, that would be fine to run an LED reading light all night.

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John


"I only exaggerate enough to compensate for being taken with a grain of salt."


LE2 #92 (sold),   Black Series HQ19   

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We have a small, cigarette lighter style inverter that we use to charge phones and computers. These are cheap and easily available at auto parts stores or camping supply stores. They work really well in the tow vehicle too, while underway.

If you mean a 12 volt USB _converter_, then yes, they are handy and efficient. If you mean an actual 12 volt inverter, that converts 12 volts DC to 110 VAC, then it is NOT efficient to plug your device pronged wall charger into it. Dropping DC voltage is fine, converting it to AC and then back to DC again is very inefficient and wasteful.

 

Most of the little cigarette lighter USB units are converters, not inverters. There are inverters:

 

https://www.amazon.com/Power-Inverters-Cigarette-Lighter/s?ie=UTF8&page=1&rh=n%3A583328%2Cp_n_feature_keywords_browse-bin%3A4889846011

 

Don't use them unless you need to charge a unit that does not have USB charging capabilities, for example, a rechargeable battery pack for a handheld comm radio or portable drill. Most of them produce very dirty, spiky current and will likely harm motors and sensitive electronics, like a laptop, and maybe a TV! OTH they are great for batteries and such. Google "modified sine wave" for info.

 

John Davies

 

Spokane WA

 

 

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"Mouse":  2017 Legacy Elite II NARV (Not An RV) Two Beds, Hull Number 218, See my HOW TO threads: https://olivertraveltrailers.com/topic/john-e-davies-how-to-threads-and-tech-articles-links/

Tow Vehicle: 2013 Land Cruiser 200, 33" LT tires, airbags.

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John,

 

We don't have a built in inverter. So we plug in a small 100 watt inverter into the cigarette lighter. It's an inverter. I've been using these little ones and large inverters on my boat for many years and am very familiar with them. You are right, it's not the most efficient way to charge something, but all we have for our Apple computers are the 120 volt chargers. And since they are already plugged into the small inverter, I also plug my tiny 120 to USB converter too. And then plug my phone into that. If nothing else is being charged, I plug my USB into the on-board stereo USB port or my Ram's USB port. Overall, the little inverter has less standby losses than a 3000 watt inverter, and it's what we have, so it works more efficiently than starting the generator, for instance, or plugging into the Ram's 110 volt outlet and leaving the computer out there until it's charged. Not trying to say there is no more efficient way to make power, just looking at the practicality of it and the scale of it and yes it is a good way to do it.

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John


"I only exaggerate enough to compensate for being taken with a grain of salt."


LE2 #92 (sold),   Black Series HQ19   

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Thank you for the info John. Tomorrow night I'll be doing my first boondocking adventure. If temperatures get cold and I need some heat do I simply place the thermostat on furnace and fan set to auto?

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Thank you for the info John. Tomorrow night I’ll be doing my first boondocking adventure. If temperatures get cold and I need some heat do I simply place the thermostat on furnace and fan set to auto?

 

 

Yes.

I set my fan on low to keep the noise down. Your choice on that. Make sure the propane is on and set the temp on the thermostat to about 68. After an hour or so you can adjust it up or down to suit your comfort. It will come on and blow warmed air out of the lower vents and in the bath. Make sure the vents are open.

 

This works just like a forced air heater in a house. The control is the same and the heat is the same. You'll find that after the initial run, it will settle down and not run very much during the night. After a while you'll find the setting that suits you best.

I've also found that our Ollie is so air tight that I like to leave a window cracked just to get a bit of fresh air. You can also leave the bathroom upper vent pushed up and open.

 

 

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John


"I only exaggerate enough to compensate for being taken with a grain of salt."


LE2 #92 (sold),   Black Series HQ19   

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Yes, set your refrigerator to gas, and thermostat to lowest comfortable temp. At least, that's what we do when camping without service. If your refrigerator is set up to run on 12v if you run out of gas, auto is an enemy. Set it to gas. Our refrigerator will suck enormous battery power running only on 12 v.

 

You are tent campers, so adapting to battery life powered by solar should be easy for you. We minimize battery consumption when living on solar, by limiting draw.

 

The biggest draw for us, most of the time, is the furnace fan. Better blankets, less draw. In cloudy weather, we minimize interior lights, as well. Bear in mind, we have a much older system.

 

I will add that our trailer runs on two agm batteries. So, I love led light, and flashlights. We charge phones and computers during the midday sun.

 

Sherry

 

Have fun, and enjoy.

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2008 Ram 1500 4 × 4

2008 Oliver Elite, Hull #12
 

 

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Thank you for the info John. Tomorrow night I’ll be doing my first boondocking adventure. If temperatures get cold and I need some heat do I simply place the thermostat on furnace and fan set to auto?

Actually, John has the older style of thermostat. Leave it on auto because if you set it on low, it will use both the AC and the heater... Strange... But true :) one of my next projects is to change this...

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Happy Camping,


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Reed & Karen Lukens with Riffles our Miniature Poodle


2017 Oliver Legacy Elite II  Standard, Hull #200 / 2017 Silverado High Country 1500 Short Bed 4x4


Past TV - 2012 Mercedes-Benz ML350 4Matic BlueTEC Diesel


Click on our avatar pic above to find the videos on our Oliver Legacy Elite II


 

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Thank you for the info John. Tomorrow night I’ll be doing my first boondocking adventure. If temperatures get cold and I need some heat do I simply place the thermostat on furnace and fan set to auto?

Actually, John has the older style of thermostat. Leave it on auto because if you set it on low, it will use both the AC and the heater… Strange… But true ???? one of my next projects is to change this…

Geo, your description is correct, when boondocking mode on furnace fan on auto or low furnace cycles on and off. I think Reed was referring to the mode switch set to auto, at which point the heat pump( if you have one installed) will try to engage, but it can't without ac power.

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STEVEnBETTY

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Mine has a "furnace" setting. I've never seen it try to go to AC on that setting, but maybe that's because I've never used it while plugged in. Although it clearly says "furnace" as one of it's modes. I wonder if maybe its the heat strip that comes on when plugged in, instead of the furnace? If so, it would run the AC fan and look like it was trying to cool. Dunno. I'll try it at home and get to the bottom of this.

 

For now, and while unplugged, try the Furnace setting and set the temp. If you use the auto on the fan switch it might go full blast when not needed. Try low if you have it.

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John


"I only exaggerate enough to compensate for being taken with a grain of salt."


LE2 #92 (sold),   Black Series HQ19   

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Mine has a “furnace” setting. I’ve never seen it try to go to AC on that setting, but maybe that’s because I’ve never used it while plugged in. Although it clearly says “furnace” as one of it’s modes. I wonder if maybe its the heat strip that comes on when plugged in, instead of the furnace? If so, it would run the AC fan and look like it was trying to cool. Dunno. I’ll try it at home and get to the bottom of this. For now, and while unplugged, try the Furnace setting and set the temp. If you use the auto on the fan switch it might go full blast when not needed. Try low if you have it.

On the new thermostats if you have ac current and the heat pump installed in the air conditioner (no heat strip from Oliver),when you set the mode to "auto" the thermostat decides weather to engage the air conditioning, heat pump or furnace.  If it's cold, the heat pump will come on first, then the furnace takes over if it's too cold.

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STEVEnBETTY

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