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Electrical system load measurements?

dyeager535 said:
Nice! I'm getting pretty excited seeing these new AC units and actual fridge/freezers that will run with fairly minimal energy requirements. I'm tempted to buy one of the 12V fridges.

I've been running my house fridge the last couple of days off the 48V battery and about 300W of solar just to see what that looks like (not good lol, probably need 800W to account for clouds and charge enough to charge for the hours of darkness), being able to camp or even road trip with a 12V powered fridge/freezer that will run for days off a 12V 100Ah (or even 50Ah) battery to me is more interesting than a cooler with ice. Being able to recharge that setup with a 200W flexible panel means runtime would be near infinite.

What sort of run time improvement do you think you'll get from the new battery? I like this 48V, but at 80+ pounds, it's not exactly fun to move around. And being plastic cased, need to be careful about transport. I've seen a fair number of RV rooftop solar panel installs, they look pretty cool and would seemingly do quite well depending on where it was parked.
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Let me know how your fridge does long term.
I am assuming you're not running a true sine wave inverter.
If you're running true sine then never mind.
I have a 4000w inverter but not sure I want to run a fridge on it.
I will run my water heater, lights even a TV.
I am thinking about I ut getting a 5000w true sine wave and use for motorized appliances.
 
I run my house refrigerator on an APC SmartUPS all the time. It does bellyache when the defroster turns on (takes about 1000w all in) but the refrigerator motor keeps going. While most refrigerators do use a synchronous motor that really hates non-sine waveforms, they do OKish on close approximations (usually). A lot of the newer refrigerators are even using stepper motors for everything else so the ones that really get ****ed up like the ice maker and whatnot are no longer a problem.

A modern inverter will tell you how close it is on the spec sheet, but you can also scope it. In reality, any decent modern inverter will run a refrigerator.

To put things into perspective, I use a whole house Champion inverter generator. The whole thing cost $900 for 8000w of glory. Runs everything in the house fine. The freezer motor does complain a little but that's because it has a junk starting circuit. If you think about that, about $200 of that is probably the motor and chassis it is in. Another $150 for the electric "generator" to make 3-phase power and a rectifier back to knock it down with some capacitors to run it into the inverter. Then the standard inverter to make 220vac 1-phase power at 8kw. So you're talking maybe $550 for a inverter that does 8kw. That's pretty impressive. And I bought it before the pandemic.
 
CyberSniper said:
I run my house refrigerator on an APC SmartUPS all the time. It does bellyache when the defroster turns on (takes about 1000w all in) but the refrigerator motor keeps going. While most refrigerators do use a synchronous motor that really hates non-sine waveforms, they do OKish on close approximations (usually). A lot of the newer refrigerators are even using stepper motors for everything else so the ones that really get ****ed up like the ice maker and whatnot are no longer a problem.

A modern inverter will tell you how close it is on the spec sheet, but you can also scope it. In reality, any decent modern inverter will run a refrigerator.

To put things into perspective, I use a whole house Champion inverter generator. The whole thing cost $900 for 8000w of glory. Runs everything in the house fine. The freezer motor does complain a little but that's because it has a junk starting circuit. If you think about that, about $200 of that is probably the motor and chassis it is in. Another $150 for the electric "generator" to make 3-phase power and a rectifier back to knock it down with some capacitors to run it into the inverter. Then the standard inverter to make 220vac 1-phase power at 8kw. So you're talking maybe $550 for a inverter that does 8kw. That's pretty impressive. And I bought it before the pandemic.
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I know it will run, I am looking long term.
A motor will run but it will get hot, and long term could degrade an burn out.
It definitely will shorten it's life.
I also have other appliances and specifically a grain mill, and it's an expensive piece that I paid $300 for and now they are $800-900.
If they last 5-8 years it's fine, but if I burn it out in a couple of years then I will spend a couple of hundred dollars more and get sinewave
 
I ran the fridge for about three days. It is a 2000w true sine wave inverter, at least according to the specs and tests done on YouTube.

One thing I hadn't considered is what if the inverter faults? With your home electric you know if power goes out if you are home. Even if it comes back on microwave clock will be flashing etc., so at least you know power was lost.

This is what happened. Not really sure why it faulted, but I happened to look at the inverter and saw the light was red, not green. Shut it off, started it, worked fine, but not interested in having it fail while I'm sleeping and the whole fridge/freezer spoils.

I got at best 350W peak out of the panels on a singular good day, and with crummy days, solar definitely wasn't keeping up. Pretty slow discharge as it was maybe 0 loss for the daytime, but you've got to account for night. Why I think maybe 800W would be the minimum. It's so dark in winter though, I question if even that would be enough.

I noticed ~500w consumption at times, probably freezer cycling? Not sure, as when I normally checked and the fridge was running, it was maybe 150W. It didn't seem to be the compressor coming on, as when I caught it, it didn't seem to really ramp down, but I didn't have a way of checking its history to see if that was a constant occurrence. Of course the inverter efficiency comes into play, so it's not 150-500W for the fridge itself, but that doesn't matter, that's what the battery is feeding.

Done with that experiment. Without going whole hog with significant storage and panels, I don't think just a battery and inverter with small solar array is practical for a home appliance like the fridge. It could work pretty easily in an RV/trailer where the whole roof could be panelled and most everything will run off 12V, but without a transfer panel or whatever they are called to run dedicated circuits off of, it's a mess of wires everywhere in a house.
 
dyeager535 said:
I ran the fridge for about three days. It is a 2000w true sine wave inverter, at least according to the specs and tests done on YouTube.

One thing I hadn't considered is what if the inverter faults? With your home electric you know if power goes out if you are home. Even if it comes back on microwave clock will be flashing etc., so at least you know power was lost.

This is what happened. Not really sure why it faulted, but I happened to look at the inverter and saw the light was red, not green. Shut it off, started it, worked fine, but not interested in having it fail while I'm sleeping and the whole fridge/freezer spoils.

I got at best 350W peak out of the panels on a singular good day, and with crummy days, solar definitely wasn't keeping up. Pretty slow discharge as it was maybe 0 loss for the daytime, but you've got to account for night. Why I think maybe 800W would be the minimum. It's so dark in winter though, I question if even that would be enough.

I noticed ~500w consumption at times, probably freezer cycling? Not sure, as when I normally checked and the fridge was running, it was maybe 150W. It didn't seem to be the compressor coming on, as when I caught it, it didn't seem to really ramp down, but I didn't have a way of checking its history to see if that was a constant occurrence. Of course the inverter efficiency comes into play, so it's not 150-500W for the fridge itself, but that doesn't matter, that's what the battery is feeding.

Done with that experiment. Without going whole hog with significant storage and panels, I don't think just a battery and inverter with small solar array is practical for a home appliance like the fridge. It could work pretty easily in an RV/trailer where the whole roof could be panelled and most everything will run off 12V, but without a transfer panel or whatever they are called to run dedicated circuits off of, it's a mess of wires everywhere in a house.
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I am working on a sub panel that will be necessities kind of, water heater, fridge, some lights, and chargers for phones and computers.
My plan is to put it on an automatic switch where the solar is primary so I am constantly using it and saving money on electricity and testing while I have a backup, the power company.
 
It may have been running a defrost cycle. I don't know how much that draws, but it's electric heat strips in the freezer. If you were in a pinch and needing to use the inverter, you could unplug the element for that duration. AFAIK it will catch up later, but during a power outage you probably won't open the door much anyway. Maybe the compressor kicking on while the defrost is running puts it over the limit. It could also mean the battery voltage got low. Some inverters are super fussy about input voltage.
 
Not sure what is driving it, but seems the dchouse eBay store is offering some fairly good discounts again. Picked up a 100Ah Bluetooth battery for $161 to the house. There is a coupon code that can be applied, as long as you say via PayPal.

I didn't look at the surge capacity but Ill probably try this in the truck as well. It's for a completely different purpose (solar powered light setup) but I'm curious how much it will try and draw off the alternator.
 
A modern house refrigerator will use heating elements to keep from frosting up. So it will flash off the condensate on the cooling elements so it will drain out of the refrigerator. If you live somewhere with humidity (above 30%) it happens enough to notice it. If you live somewhere with 50% and have a family that stops and stares into the refrigerator calculating PI to the 100th digit, then it runs a lot. Most refrigerators have either a 450 or 850 watt element. Some just have a pair of 450.

I feel like the linear compressor ones are even weirder and cycle the strip-style elements more, but I'm not sure why.

I have all my major appliances on either a UPS or some other type of power conditioner. My refrigerator will last about 2 hours on a 1500va UPS unless it goes into a defrost cycle... then it's like 4 minutes. When just the compressor is running, it claims it will run about 210 minutes (very optimistic). I usually aim for my shit to go about an hour on battery because that's about how long it takes me to drive home and cut over to generator.
 
I now have 3 of these:

I bought two for me and one for my parents. I have all 3 charged up. I used my Noco battery charger and its lithium profile pushes at about ~13.95 volts. The batteries took the full 10amps the charger can do... and fully charged to 280ah per the bluetooth app.


I bought two of these:

Easy to swap out. I am using the constant voltage option and I set it to 14.2v. Theory being it shouldn't boil the lead acid (chassis) batteries too bad if I were to try to charge them using it (due to voltage drop on long wires, it's down to about 13.95 at the front of the motorhome at the isolating solenoid).



My parents' motorhome has an even smaller battery compartment so he needs to build a battery hold down and do some other work to make it fit. He made fun of me how every time there is a holiday I put him to work. Yesterday I went there to put on the tires/wheels I bought them for the motorhome and drop off the battery and converter. He thought we were done once I put the hub caps back on and loaded his tires/wheels into my truck and then out came the battery. haha. Their pair of group 24 batteries



I already have one in my motorhome and it's amazing how the battery maintains perfect voltage on peaky loads (hydraulic pump for my leveling system is abusive). I need to make a battery hanger for the frame rail for the other one on my motorhome. I think I'm going to "seal" it up using electrical tape and silicone (terminals) and not bother with making a battery box. It is not sealed very well otherwise.
 
Losing power to a fridge for an hour is no big deal, unless somebody is there holding the door open. When we have extended power outages, I turn the generator off at night because I don't like burning a gallon of propane an hour to run night lights. Even the deep freeze downstairs is well below freezing when morning comes.
 
Blue85 said:
Losing power to a fridge for an hour is no big deal, unless somebody is there holding the door open. When we have extended power outages, I turn the generator off at night because I don't like burning a gallon of propane an hour to run night lights. Even the deep freeze downstairs is well below freezing when morning comes.
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In Lebanon, during the war in the 70s and 80s, first we didn't have power for 2 years then generators started coming and we quickly realized we couldn't sustain non stop generators so we started a shutdown at night, which was ok but then we switched to a 6hrs on 6hrs off schedule which worked better.
Now the power company is doing that schedule to keep up because the recent war damage and the gaps are filled with huge neighborhood generators.
Here in this society we have been blessed and pampered and we try to plan for a continuing of this pampering in the event of a collapse, but instead we need to prepare for sustainable lifestyle that can get us through the bad times until we can make it better again.
 
I am setting up a small emergency solar setup to keep one fridge, water heater, and some lights and I have a 10k generator.
It's enough to keep going and surviving in reasonable comfort
 
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