Post by papaof2 on Mar 4, 2021 17:24:46 GMT -6
It's just $99 plus $9 shipping!
There is much hype - and some outright lies - in the solar items pitched to the mass market. The Chinese venfors are especially bad about twisting the numbers and making things sound wonderful. An example, this item:
www.banggood.com/12V-or-24V-DIY-Solar-System-Kit-Soalr-Charge-Controller-18V-20W-Solar-Panel-800W-Solar-Inverter-Solar-Power-Generation-Kit-p-1703629.html
It sounds like everything you need (except the battery) to set up a solar power system and power your fridge or whatever. The PWM charge controller is rated to handle 40 amps. At 12 volts that's 480 watts so it sounds pretty good. The inverter is rated at 800 watts - that might run your fridge IF it can start it: compressors often need 4 to 10 times as much power for starting as for running. There's even a solar panel - but the fine print tells you it's a 10 watt panel.
If you have a big enough battery, you can get AC power for a little while, but a 12 volt, 100 amp hour (AH) lead-acid battery (easiest to find locally) only has 600 watt hours of power available if you limit the discharge to a reasonable point - something that doesn't kill the battery in 100 uses. 600 watt hours / 800 watts (ignoring the inverter's less than 100% efficiency) is 0.75 hour or 45 minutes. That 10 watt solar panel will need more than 60 hours of full sun to recharge the battery - again, ignoring the inefficiency of the charge controller). If your useful winter sunlight is 3 hours/day (my location), then that's 20+ days to recharge the battery from that one use.
By the way, ignore the 12 or 24 volt info in the link - that solar panel only delivers 17 volts under load so it can't charge a 24 volt battery. The charge controller can work in a 24 volt system, but you'll need more solar voltage than this panel can deliver.
And look closely at the inverter specs - it's output is 220 volts which doesn't work for the US or Canada where the AC outlets deliver 120 volts. Fine for much of the world, but not this continent.
Think maybe you were lied to?
There is much hype - and some outright lies - in the solar items pitched to the mass market. The Chinese venfors are especially bad about twisting the numbers and making things sound wonderful. An example, this item:
www.banggood.com/12V-or-24V-DIY-Solar-System-Kit-Soalr-Charge-Controller-18V-20W-Solar-Panel-800W-Solar-Inverter-Solar-Power-Generation-Kit-p-1703629.html
It sounds like everything you need (except the battery) to set up a solar power system and power your fridge or whatever. The PWM charge controller is rated to handle 40 amps. At 12 volts that's 480 watts so it sounds pretty good. The inverter is rated at 800 watts - that might run your fridge IF it can start it: compressors often need 4 to 10 times as much power for starting as for running. There's even a solar panel - but the fine print tells you it's a 10 watt panel.
If you have a big enough battery, you can get AC power for a little while, but a 12 volt, 100 amp hour (AH) lead-acid battery (easiest to find locally) only has 600 watt hours of power available if you limit the discharge to a reasonable point - something that doesn't kill the battery in 100 uses. 600 watt hours / 800 watts (ignoring the inverter's less than 100% efficiency) is 0.75 hour or 45 minutes. That 10 watt solar panel will need more than 60 hours of full sun to recharge the battery - again, ignoring the inefficiency of the charge controller). If your useful winter sunlight is 3 hours/day (my location), then that's 20+ days to recharge the battery from that one use.
By the way, ignore the 12 or 24 volt info in the link - that solar panel only delivers 17 volts under load so it can't charge a 24 volt battery. The charge controller can work in a 24 volt system, but you'll need more solar voltage than this panel can deliver.
And look closely at the inverter specs - it's output is 220 volts which doesn't work for the US or Canada where the AC outlets deliver 120 volts. Fine for much of the world, but not this continent.
Think maybe you were lied to?