diy solar

diy solar

Newbie looking for solid upgrade advice.

No you got it exactly right. Avoid converting when possible.
Your WiFi probably has a wall power supply, if you are lucky, it will accept 12V.

You may become accustomed to looking at things in this manner more and more.
I will be looking into DC freezers Not sure how efficient they are though. Am I loosing much energy charging my batteries for led lighting and fans from USB ports and dc output or is it an insignificant loss?
 
I will be looking into DC freezers Not sure how efficient they are though.
For the money? A small 120V chest freezer is a coupla hundred bucks and the lesser-priced DC ones are coolers or not good purchases imho
Am I loosing much energy charging my batteries for led lighting and fans from USB ports and dc output or is it an insignificant loss?
You do lose some with usb. Often, they use heat to lower the voltage. There’s no lossless conversion. If you’ve got twenty usb charger sockets running that might be ‘significant.’ Measure the current with nothing plugged into one.
Don’t get overly concerned about “losses.” This isn’t money out of your pockets- it’s just the ancillary effects of enabling yourself to be shtf ready. Like having solar panels- you can’t do without them
Would a 1000 W PSW 2000 peak do the job? I'll also be running a CB radio on DC votage. Am I wrong for running as much DC current as I could? I figured it would save on conversion to AC.
The more the dc the better but again: savings on conversion…relative.

1000W- that’s like 8A 120VAC
Probably enough but in my case the short-duration startup on small fridges can be 800-900W and I wanted more headroom for longevity (of the inverter) so I bought 1200W and recently acquired a backup (1500W, same brand).
I’d say do 1200W to be a little less stress when your freezer starts. Unless you do DC but the DC stuff is pricey even if it’s “good” and I’m assuming you’ll go 120V

The other two things about 120V is that it’s convenient for so many things and it’s efficient over distance.

The MSW inverter could be used exclusively for the slow cooker and coffeemaker but then again, inverters are lossy so take the hit once with pure sine and try to run not at 100% of rating- I like to understress things by 15-20%

My thoughts ymmv
 
For the money? A small 120V chest freezer is a coupla hundred bucks and the lesser-priced DC ones are coolers or not good purchases imho

You do lose some with usb. Often, they use heat to lower the voltage. There’s no lossless conversion. If you’ve got twenty usb charger sockets running that might be ‘significant.’ Measure the current with nothing plugged into one.
Don’t get overly concerned about “losses.” This isn’t money out of your pockets- it’s just the ancillary effects of enabling yourself to be shtf ready. Like having solar panels- you can’t do without them

The more the dc the better but again: savings on conversion…relative.

1000W- that’s like 8A 120VAC
Probably enough but in my case the short-duration startup on small fridges can be 800-900W and I wanted more headroom for longevity (of the inverter) so I bought 1200W and recently acquired a backup (1500W, same brand).
I’d say do 1200W to be a little less stress when your freezer starts. Unless you do DC but the DC stuff is pricey even if it’s “good” and I’m assuming you’ll go 120V

The other two things about 120V is that it’s convenient for so many things and it’s efficient over distance.

The MSW inverter could be used exclusively for the slow cooker and coffeemaker but then again, inverters are lossy so take the hit once with pure sine and try to run not at 100% of rating- I like to understress things by 15-20%

My thoughts ymmv
Thanks again for your valuable input. I have a small 60 W mini fridge that I could utilize if needed. But first I need to generate more power. I will be purchasing another 160 W poly panel or 180 W mono panel with another 20ft 10awg cable with my $200 upgrade budget. The PSW inverter will have to wait but will be next on my list. Do you feel Mono panels are significantly better? It will be running on a seperate controller. The 180 W mono is only $20 more than the 160 W poly. The wife won't like the color mismatch though. ?
 
Do you feel Mono panels are significantly better? It will be running on a seperate controller. The 180 W mono is only $20 more than the 160 W poly. The wife won't like the color mismatch though. ?
I'd keep the wife happy and get another poly. The only thing "better" about the mono is 20W more output. A potential downside is you introduce a (slightly) mismatched panel into your array. Here's an article to help you understand how mismatched panels affect output depending on the configuration. It should help you make an informed decision based on your system and needs.

 
I'd keep the wife happy and get another poly. The only thing "better" about the mono is 20W more output. A potential downside is you introduce a (slightly) mismatched panel into your array. Here's an article to help you understand how mismatched panels affect output depending on the configuration. It should help you make an informed decision based on your system and needs.

The Mono panels will be on a seperate Solar charge controller.
 
I don't recommend exceeding the specs on those little PWMs.

As for the battery charging current, from what I see online the manufacturer recommends charge current to be under 30A for a single battery. With two in parallel, each or your batteries will be receiving half the charge current. So if you're pushing 36A into the bank, each would be getting 18A. That is a nice charge rate for the gels.

The simplest way to make sure you are splitting the current evenly is to wire your batteries up as shown below. Your charge sources and load devices should all connect to the positive terminal of one battery and the negative terminal of the other:

View attachment 65070
Should my inverter be wired up the same to split the current going out evenly?
 
Well I decided to go with another 160 W panel and duplicate what I have with another controller and watt meter. . This way I'll have the capability of adding another 160 W panel and have 640 watts of panels to work with.Thanks for everyone's help. I'll let you all know when I have it up and running with the results.
 
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Just keep in mind that if you kill the fridge the pure sine inverter will seem a whole lot less expensive suddenly
I have 2 refrigerators and a mini fridge. In a bind I would be willing to take that chance on the older one that cost me nothing. Maybe I'll give it a try today. If I bought a PSW inverter instead of upgrading my panels I would not have enough power to run any refrigerator. I'll be in the hunt for one next month. But for now I need to bring in the power first and work on distributing it second. Buying a PSW would be like having a nice car without tires on it. At least I have an old junker that just might get me there and back until I can afford a new one. Thanks again for your input.
 
So my first refrigerator test with the newer 2.7 CFL whirlpool Mini fridge and the MSW inverters was a complete failure. The fridge did not respond at all the 2000W inverter and only hummed a little and shut down with the 300W inverter. When plugged into the wall it comes right on. Next up is the older full size. It's a big no go also. I will definitely be buying a PSW inverter soon as possible. Live and learn.
 
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So my first refrigerator test with the newer 2.7 CFL whirlpool Mini fridge and the MSW inverters was a complete failure. The fridge did not respond at all the 2000W inverter and only hummed a little and shut down with the 300W inverter. When plugged into the wall it comes right on. Next up is the older full size. It's a big no go also. I will definitely be buying a PSW inverter soon as possible. Live and learn.
Good for you for running a test first rather than being up a creek in an emergency.
 
Good for you for running a test first rather than being up a creek in an emergency.
I've seen a couple cheap KRXNY $100 PSW inverters that are 1000w with 2000w peak. Will this run a fridge? Can you recommend a decent unit at a good price? Specs below

Specifications :

DC Voltage12V/24V/48V
Voltage Range10-15VDC or 21-30VDC or 42V~60V
NO Load Current Draw<0.8A
Efficiency>90%
DC ConnectorCables With Clips or Car Adaptor
AC Voltage110V-120VAC
Continuous Power1000W/2000W
Surge Power2000W/4000W
WaveformPure Sine Wave
Frequency60Hz
AC Regulation3%
Low Voltage Alarm10DC±0.5V or 20.5DC±1V or 42DC±1V
Low Voltage Shut Down9.5DC±0.5V or 19.5DC±1V or 41DC±1V
Over LoadShut Off Output
Over Voltage Shut Down15.5V or 30.5V or 61.2V
Over ThermalShut Off Output Automatically
FusesShort Circuit
Working TemperatureBetween -10centi and +50centi
Working Humidity20%~90%RH non-condensing
Storage TemperatureBetween -30centi and +70centi
StartSoft Start
Cooling WaysCooling Fan
Total Harmonic Distortion THD<5%
Machine Size(mm)300*130*70/360*160*80mm
Packing Size(mm)345*150*80/385*220*135mm
Net Weight(kgs)1.6/2.2 kgs ( 3.5/4.8LB )
Gross Weight(kgs)2.2/2.8kgs ( 4.8/6.2LB )
DisplayLED Display

Screenshot_20210919-124358_Facebook.jpg
 
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Personally I wouldn’t

Giandel is inexpensive yet gets good reviews overall and people have had good things to say about warranty support.

I have a 1200W giandel pure sine inverter that’s been running for 3+ years, 24/7 since May? or so. Runs my 5.x CF mini fridge and shop vac fine.
I wouldn’t shop below that. It’s less about dollars and more about use performance.
 
Personally I wouldn’t

Giandel is inexpensive yet gets good reviews overall and people have had good things to say about warranty support.

I have a 1200W giandel pure sine inverter that’s been running for 3+ years, 24/7 since May? or so. Runs my 5.x CF mini fridge and shop vac fine.
I wouldn’t shop below that. It’s less about dollars and more about use performance.
I shall take your advice and will keep an eye out for a Giandel. Thanks
 
So as it turns out. My 2000W MSW appears to be defective. I've only used it for inductive loads like a blow dryer, heater, slow cooker and it seemed to work fine. It was bothering me that the 300W MSW would turn on the mini fridge and the 2000W would not. So I have a spare 2000W that the plastic lugs adapters were broken when I received it and they sent me another free of charge. I got to keep the old one. I swapped out the parts and fired the little fridge up with no problems. I'll do some testing tonight just for backup and power requirements. At least I'm not totally stuck if something were to happen. I'm still planning on purchasing a PSW but at least this buys me a little time.
 
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Testing of the Whirlpool 2.7 Cf Mini Fridge and unknown 2000W MSW inverter completed. I got the fridge down to temperature prior to testing using house electricity.
Test duration 12 hrs
No food in fridge
Opened door 3 times briefly
Temperature maintains 37 deg F no issues with remote thermometer.
Compressor temperature maintains between 104 and 114 deg F with no noise or hum. Using Infrared thermometer
Starting resting voltage was 12.95
Finish resting voltage was 12.65

I figured 0.3 V is approximately 15% of my total 200 Ah batteries (30 Ah 360W) in 12 hrs. If my calculations are correct that's 60 Ah per day which equals 720 Watts. This is pretty much on par with the Energy star annual 214 Kw = 568 Watts per day. Which would leave the MSW inverter with being at 81.5% efficient with a small load. I don't have a watt meter that will read MSW accurately so that leaves a good margin of error.

So the conclusion of my non scientific testing is Not Too Shabby! This might just work in a pinch. The Big Fridge will be next up.
 
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