Electrical needs calculations?
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I'm afraid in order to be useful you need to state the maximum number of days.ValerieP said:
If more than 4-5, never mind, need to invest a lot more than say only two nights off grid.
Unless you're willing to buy and carry a small generator, that can help a lot.
MrAlvinDude
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The fridge
This is the data that I could easily find on the Whynter 62 qt dual zone fridge.
https://www.whynter.com/product/whynter-62-quart-dual-zone-portable-fridge-freezer/
The motor uses 65W when it is running, but it will not be running all the time. A compressor fridge typically duns only a few minutes at a time, and then rests for quite some time. So all in all, it might run for 20 minutes every hour. But it could also be less.
So to get better numbers, you need to hear from someone who own and use this fridge.
When the motor is running it uses 65W (65W / 12V = 5.42A) or 5.42Ah,
but if the motor is only active 20 minutes every hour, then the actual draw is: 5.42Ah / (20/60) = 1.8Ah every hour.
And this would become 1.8Ah x24h = 43.2Ah per 24h
But like I said, hopefully this is actually less, and to get a more precise idea, numbers from actual uses are needed.
Oh, here is a review:
http://www.cheaprvliving.com/cookin...-and-dometic-12-volt-compressor-refigerators/
And in the review situation it seems to only run a total of 4 hours a day. So only 10 minutes every hour.
This makes it use 5.42Ah / (10/60) = 0.90Ah per hour or 21.68Ah per day.
You should never draw more than 50Ah from a 100Ah battery, but even so, a 100Ah battery could possibly keep this fridge running for a couple of days.
How much power is actually used does however also depend on the temperature where it is placed, how often it is opened and how much new items gets put into it.
But even so, it might still run for a couple of days on a 100Ah battery.
This is the data that I could easily find on the Whynter 62 qt dual zone fridge.
https://www.whynter.com/product/whynter-62-quart-dual-zone-portable-fridge-freezer/
The motor uses 65W when it is running, but it will not be running all the time. A compressor fridge typically duns only a few minutes at a time, and then rests for quite some time. So all in all, it might run for 20 minutes every hour. But it could also be less.
So to get better numbers, you need to hear from someone who own and use this fridge.
When the motor is running it uses 65W (65W / 12V = 5.42A) or 5.42Ah,
but if the motor is only active 20 minutes every hour, then the actual draw is: 5.42Ah / (20/60) = 1.8Ah every hour.
And this would become 1.8Ah x24h = 43.2Ah per 24h
But like I said, hopefully this is actually less, and to get a more precise idea, numbers from actual uses are needed.
Oh, here is a review:
http://www.cheaprvliving.com/cookin...-and-dometic-12-volt-compressor-refigerators/
And in the review situation it seems to only run a total of 4 hours a day. So only 10 minutes every hour.
This makes it use 5.42Ah / (10/60) = 0.90Ah per hour or 21.68Ah per day.
You should never draw more than 50Ah from a 100Ah battery, but even so, a 100Ah battery could possibly keep this fridge running for a couple of days.
How much power is actually used does however also depend on the temperature where it is placed, how often it is opened and how much new items gets put into it.
But even so, it might still run for a couple of days on a 100Ah battery.
Better to get separate not kombi models. Xantrex hardware is OK but customer service sux. Better to do without any inverter if at all possible, or at least as small as possible, little ones are so cheap you can get one per AC device.ValerieP said:
good unit, hot weather as a freezer maybe 60-80AH per day, cool weather set to 38° half that.ValerieP said:
Big load!
Again, forget the heater and rice cooker completely off solar, only off mains, or maybe, if you have lots of batt juice left in the evening, and know you're plugging into mains power tommorrow.
Otherwise propane for both heat and cooking (start a new thread)
Genny every morning before solar, until bank is 85% full, waste to run it the further 3-5 hours necessary to get to 100%, but 400W solar will do that easy even on a 200+AH bank.ValerieP said:
It's the fridge not TV.
Yes there are, you'll soon be able to figure yourself.ValerieP said:
Get the AH counters mentioned, a decent DMM, you'll need them even after you're all set to confirm everything's working well, later troubleshooting.
highdesertranger
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well it sounds like you are getting a handle on this. it's good that you don't have all your gear yet. take the TV for example it sounds like you don't have one yet, get a 12v TV that way you eliminate running it through an inverter. try to do this as much as you can. highdesertranger
If you're streaming or playing vdo rather than receiving broadcast
Most low-consumption flat screen monitors (as in computer screens) are native DC with a power brick.
Just check voltage, polarity and pin type (usually DC5521) put the the brick away for mains power, off batteries run direct DC.
Lots bigger and cheaper than specialized 12V TVs marketed for RVs.
Can even look for one native 12V, walk through Best Buy looking at the specs on their power bricks.
Add-on receivers not expensive, Roku, little NUC or cheap linux miniPC running Kodi or Plex, better home theatre setup in the van than most people have at home.
Go 48" if you have the power (and room) not 4K 1080p is fine.
Most low-consumption flat screen monitors (as in computer screens) are native DC with a power brick.
Just check voltage, polarity and pin type (usually DC5521) put the the brick away for mains power, off batteries run direct DC.
Lots bigger and cheaper than specialized 12V TVs marketed for RVs.
Can even look for one native 12V, walk through Best Buy looking at the specs on their power bricks.
Add-on receivers not expensive, Roku, little NUC or cheap linux miniPC running Kodi or Plex, better home theatre setup in the van than most people have at home.
Go 48" if you have the power (and room) not 4K 1080p is fine.
And that's the worst electrical connection type ever invented, IMO avoid like the plague.ValerieP said:
Research stranded tinned (ideally marine grade) wire, Anderson power poles and other crimped terminations like ring and spade and butt.
Buy cheap examples, maybe pay a neighborhood tinkerer or nerdy kid for a couple hours.
Worst case pay a pro.
Custom cabling cheaply done right by genuinedealz.com
jacks18614
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The converter on my 19" 12v Led Samsung reads 110ac to 2.5A DC.
see above for tolerance range comment, 12V stabilizer's not expensive.jacks18614 said:
Need pin size and polarity too.
That current rating is maximum of the transformer output, need a Watts Up to measure actual AH per hour consumption.
They can be quite large, harder to find a discreet place to mount.ValerieP said:
Usually doesn't actually save much money if it's good quality.
Very common the charger part is not high-amps enough to properly care for the bank, especially for AGM.
Often the best strategy is to choose a small and least expensive inverter for a specific load device, rather than just one huge inefficient and expensive one.
A different type or size of inverter is often needed as things change, it is easier to swap out and sell a standalone, leave the charger in place.
Also when one "side" of a kombi unit breaks, they rarely are worth repairing, have to buy a whole new one.
Oh yes, very important fact, there is a single path for in and out really complicates or makes impossible using combiners or DC-DC charging of multiple banks.
And finally many systems are best served by a design where a charging buss is kep isolated from a load buss, also impossible with a kombi unit.
I believe Roaming Kat may have been caught out by that last aspect.
There are probablt some more reasons too, but that's enough for now?
And finally many systems are best served by a design where a charging buss is kep isolated from a load buss, also impossible with a kombi unit.
I believe Roaming Kat may have been caught out by that last aspect.
There are probablt some more reasons too, but that's enough for now?
Almost There
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ValerieP said:
First, there are different quality 'cigarette lighter' type connectors. The ones' that come with a vehicle are the lowest of the low quality. Blue Sea or Marinco are much better quality.
And then there's Anderson Pole connectors. Great for some stuff, not useful for others.
Personally, I use Marinco outlets and then hard-wired the fridge and the freezer directly in to their own circuits on the fuse block.
ValerieP said:
The inverter needs to be sized for the smallest you can get away with and IMO, switched so that you only turn it on when you need to use it. The battery charger needs to be sized correctly for the battery bank that you're powering. Getting a 2 in 1 device that meets both of those needs correctly might be pretty tricky so you usually end up sacrificing something somewhere along the line. Buying exactly what you need for each need most often works better.
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