Inverter recommendations

Or use the auto-off feature. Although the shortest setting at one hour seems a bit long. Ten minutes would seem to be plenty.

In the states a friend loaned me his Keurug and a big box of assorted coffees. So I plugged it in. My electric bill jumped from twenty-one dollars a month to thirty five.

Upon unplugging the bill went back to 21.

I have never encountered a table top kitchen appliance as greedy as that Keurug.

If I win a lottery and subsequently can report "I have people that do that for me" then the Keurug may be a viable option. Wow! What an energy monster!

MrWizard wrote:

But the Keurig and expresso makers are between 1200-1500 watts

The Keurig's also use about 800W to keep the water at their specified temp.

smkettner wrote:
GoPower 300w sine wave idle spec is 260 milliamps. 2000w sine wave is closer to 2 amps at idle.

My 175W Gopower has less than 100 milliapms idle current, I can hardly see it (the manual says 0.2A idle, but it draws way less). Alright, idle current is a different creature from the current "added" due to the losses when running some load. Still, 6A difference btw the "losses current" of 1,500W inverter and 300W inverter - considering that their idle current should differ by less than 2A, and at 4A load the inverter is practically idling - this is odd. Bad 1,500W inverter, IMO.

One good idea that I borrowed from Fred was L-brackets for solar panels, with rivet nuts in the side of the panel frame. Takes some time and accuracy for measuring and drilling, but the result is a reliable install with few parts and no shaking. Very happy.

Low idle draw is important when the inverter is left on inadvertently for an extended period.
GoPower 300w sine wave idle spec is 260 milliamps. 2000w sine wave is closer to 2 amps at idle.

I have posted before that Fred's numbers don't match mine at all. I don't know what is the situation there. Perhaps he is using 1990s equipment and I have newer switch- mode equipment, no idea.

Eg with a 1000w PSW inverter (although I don't think the PSW vs MSW matters in this case), I can run a CFL bulb in a 120v lamp that draws a total of 1 amp DC as seen on the Trimetric. It throws more light than a regular 12v double lamp that draws 3 amps DC.

I do see a bigger draw using the 2000w inverter to run the same thing as the 1000w inverter, but not much. It has to do with the inverter's efficiency curve where you compare the actual load vs the max inverter watts. Best efficiency is just over half the inverter rating. It hurts more if you run a 190w load on a 200w inverter than it would on a 300w inverter.

That is often confused with the "stand-by draw" of an inverter with no load. Not the same thing at all. You don't add the stand-by draw to the load draw for some kind of total. Lots of people on here seem to think that is the case.

Fred, with all due respect - and I mean it - 35 AH a day just for refrigerator and CO/propane detectors is way too much. In my trailer it's more like 12 AH a day, though my CO detector has its own AA battery. 35 AH would cover not only the parasiti loads mentioned above, but also lights, pumps and some TV or laptop time.

Now, about 1,500W inverter drawing 10A and 300W inverter only 4A with the same load - this means inverter losses 6A when the load is ~4A. I wonder whether I am the only one who finds this strange. Probably something was wrong with that 1,500W inverter.

About step-by-step photos or videos inverter wiring - OP asked. These RV mods are all DIY, members here would have some photos but with loads not exceeding 10A DC you don't need a guide.
DC input: Place 150-300W inverter within 6-7ft from the battery (extend its OEM cable #18 with a piece of #10 necessary), and connect it to the battery posts. With 20A inline fuse if you wish so.

AC output: I "think" that you can hard-wire inverter output to the closest 110V branch, ex. connect it in parallel to one of your 110V receptacles. Not to 110V 50A input outside, but exactly to wall receptacle inside. Electricians will frown on this, but you have mere 10A current. Make sure that 110V doesn't feed into converter - you might have to install a on-off switch on converter, or your converter might already have one. Don't forget to turn the inverter off when you are on shore power.

Yes, small MSW inverters are dirt cheap. Paid $20 for my 175W Gopower. LCD TV may or may not work on MSW, but 175W is enough for this load.

Hi,

I have 4 batteries, and very rarely used the 1,500 watt inverter that I installed in my motorhome. It just used to much power. If I was watching TV, using the Direct TV dish, and total amp draw from my battery was 10 amps, changing to the portable 300 watt inverter reduced that to only 4 amps.

SO I would recommend a 300 - 500 watt portable inverter. Scrap the idea of making coffee with the inverter, it draws way to many amps for a 2 battery set up. The 160 watt solar panel can put back about 50 amp hours per day. Your RV will consume about 35 AH daily to run just the CO meter, propane detector and refrigerator. I have a pair of 120 watt panels, 90 watt and 75 watt. This keeps my ahead of my power used.

You might want to add another panel. SunElec.com is a great place, with great prices. I made my own mounts and run UV rated wire myself. You can get that at Home Depot.

As for the coffee, you can make it with a Mr. Coffee filter holder. Take 3 coffee mugs, and a pot of boiling water. Put in a filter and 3 TBS of coffee. Add a cup of boiling water, (while over cup #1) and then move to mug #2. Add another cup of boiling water (and perhaps a little more coffee) When done making coffee, move to the last spare mug. Don't drink the drippings from the last mug, it will be really saturated and concentrated taste, strong as heck. You can make refils - just add more hot water while over the empty mug.

OR get a 1,000 watt MSW inverter to just run the coffee maker (and whatever type of stuff) and run it only when you need to run the big loads. Run the TV from perhaps a pure sine 250 watt inverter, or a more energy efficient 100 - 500 watt MSW inverter. They are fairly low cost (MSW) you can get a 500 watt Coleman MSW inverter for about $40 at Costco a few years ago.

The 1,000 watt MSW inverter to run a coffee maker would require #4 wire to carry the 100 amps, and be very close to the battery. (say within 6') but not in the same battery compartment, as battery gas is hazardous to the inverter, and explosive too). Then run a #14 or #12 extension cord to the coffee maker, and make coffee that way. Using warm water will help lower the amp draw on the inverter.

Most 1,000 watt MSW inverters will draw about 2-3 amps just sitting there, in addition to the amps they might draw to power the load. So 24 - 36 watts in with 0 watts output, and when loaded to say 800 watts out, input might be 1,000 - 1,100 watts, or close to 100 amps per hour. The battery voltage also drops significantly under a 100 amp load. So it might be 12.5 volts while running the furnace, but drop to 11 volts under a 100 amp load running the coffee maker, and consume 100 amps to put out 7 amps AC at 120 volts or about 840 watts.

Have fun camping!

Fred.

I agree with other people - the beauty of small <300W inverter is that you can leave it always on. Transfer switch, or a on-off switch on the converter and yellow RV extention cable from inverter to OEM shore power input is all you need.

OTH, without a big battery bank and big inverter - and if you are totally against any other way of making coffee, you would have to "exercise" your generator twice a day, or whatever number of daily shots you need to get by :)

Living with addictions is tough.

This is my 300w GoPower sitting behind my electric panel.
Two transfer relays in the black box to the left. I can't see the 12v connection but ir should be on the right of the inverter and it connects behind. Red battery cable is the very bottom right but the connection is out of view. Pic is looking in with the electric panel removed.

I chose GoPower for lowest idle draw and provision to add a remote switch.
See three position power switch on front and green connector just below.
Sorry no wireless :(

If installing to day I would use the small KISAE TS15A 15A Automatic Transfer Switch $50
I have two switches because I wanted power on both convenience outlet circuits. These are connected after the branch circuit breaker.