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12v or 24v ?

ryankshaw said:
no, it is 200 watt hours used. Because when you are talking about the amount of energy used over a period of time, the unit is watt hours


no, it is 800 watt hours used.

you're still getting watts and watt hours confused. I'd google https://www.google.com/search?q=watts+vs+watt+hours
Click to expand...

If I have a 200 watt draw over a period of one how how man watts did I use? 200w x 1hr = 200 watts used is that not correct?

If that is correct then how many watts did I use at
200w x 4hrs = 800wh ?
Seems to me it would be 800 watts consumed.

See attached photo. 800wh = 800 watts
 

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Ronifer said:
If I have a 200 watt draw over a period of one how how man watts did I use? 200w x 1hr = 200 watts used is that not correct?

If that is correct then how many watts did I use at
200w x 4hrs = 800wh ?
Seems to me it would be 800 watts consumed.

See attached photo. 800wh = 800 watts
Click to expand...
No, a watt is a rate, it tells you how much power is being delivered at any point in time. One watt corresponds to one Joule per second. Saying you used a watt would be like saying you used a mile per hour.

A watt hour is an expression of how much energy is stored or used. A 10 watt hour capacity battery can deliver 10 watts for one hour, or ten joules every second for one hour.
 
It’s just like driving 60 miles is not the same a driving 60mph.

For a technical thing as PV and electricity, units and terminology is such a huge factor when talking about your system and questions. By adding ambiguity to posts and using the wrong units it just makes it harder for those to help out.

This is just my 2cents, take it for what you want, you def seem like you know your stuff I think it’d be cool to see how your entire system is set
Up and works as I’m a huge fan of redundancy. Just so much gets “lost in translation” when posting in the internet.
 
Reed Cole said:
No, a watt is a rate, it tells you how much power is being delivered at any point in time. One watt corresponds to one Joule per second. Saying you used a watt would be like saying you used a mile per hour.

A watt hour is an expression of how much energy is stored or used. A 10 watt hour capacity battery can deliver 10 watts for one hour, or ten joules every second for one hour.
Click to expand...

200w load x 4 hours = 800wh so how many total watts were consumed?
 
740GLE said:
It’s just like driving 60 miles is not the same a driving 60mph.

For a technical thing as PV and electricity, units and terminology is such a huge factor when talking about your system and questions. By adding ambiguity to posts and using the wrong units it just makes it harder for those to help out.

This is just my 2cents, take it for what you want, you def seem like you know your stuff I think it’d be cool to see how your entire system is set
Up and works as I’m a huge fan of redundancy. Just so much gets “lost in translation” when posting in the internet.
Click to expand...

My point is 800w used is 800 watts used. I understand that can be 100w x 8hrs = 800wh
Or that can be 200w x4 hrs = 800wh
At the end of both equations it equals 800wh watts used and that translates to 800w. Everyone keeps say I am confused which I am not at all. If the above isn't true please explain how 800w and 800wh in this case are not the same. I understand the terms and how they are used as well as determined. I am simply stating that at the end of the day I have used 800w. Why that isn't being understood I have no idea.
 
Ronifer said:
200w load x 4 hours = 800wh so how many total watts were consumed?
Click to expand...
None or maybe an infinite amount, watts are a measurement of how much power is being used at any one point in time. Consuming watts doesn't compute.

You could Google this and watch some videos or read some short explanations. Or not but you should except that nearly every other person with a basic understanding of electricity will use the term watt hours, when talking about how much energy they stored or used.
 
Ronifer said:
My point is 800w used is 800 watts used. I understand that can be 100w x 8hrs = 800wh
Or that can be 200w x4 hrs = 800wh
At the end of both equations it equals 800wh watts used and that translates to 800w. Everyone keeps say I am confused which I am not at all. If the above isn't true please explain how 800w and 800wh in this case are not the same. I understand the terms and how they are used as well as determined. I am simply stating that at the end of the day I have used 800w. Why that isn't being understood I have no idea.
Click to expand...
So why can’t you just say 800whrs? You seem to be very adamant on using wrong units.

Cause when I get pulled over and the cop asked me how fast i’m going I don’t say 10 miles, you know my normal commute to work. He cares that I was doing 80mph in a school zone cause I was late ?

Back to your original question

What’s you decide 24v or 12v?
 
Back to the op point - the reason 24v is mentioned is that the amp requirement will be reduced. A 600w inverter will be supplying a huge amp draw at 12v, thats the reasoning behind the limitations. Wire gauge size to the inverter will be 4/0 at 12v, but only 2/0 needed for 24v as the amperage draw is reduced by a factor of 2. This is cheaper wiring and less amps in the wire. At 600w you would be pulling 50amps, so maybe not a huge deal, but at 24v you would only be pulling 25. At 600w not really much of an issue, at 4000w it is.
 
Reed Cole said:
None or maybe an infinite amount, watts are a measurement of how much power is being used at any one point in time. Consuming watts doesn't compute.

You could Google this and watch some videos or read some short explanations. Or not but you should except that nearly every other person with a basic understanding of electricity will use the term watt hours, when talking about how much energy they stored or used.
Click to expand...

I already have a full understanding of watt and watt hours. Maybe those can accept that that 800wh = 800 watts in my context that I used it in. It was real simple just to accept that it was infact still correct no matter what. I mean when someone keeps telling me I am confused when I was in fact correct because they are so stuck on the aspect of watt vs watt hours I can't help that I laid it out in simple. 800w ?
Further more I didn't ask anyone to calculate my wh for me as I had already accomplished that myself. Easy as falling off a log.
Basic understanding? How much more basic it the fact its 800w? Lord. I have done residential a/c and light commercial for a living. I halso have extensive dc automotive experience so I have more than a basic understanding just some like to complicate the simple.
I wasn't asking for a class on watts and watt hours. I simply stating i would use 800w total. None of that had anything to do with my original question.
 
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So you just chose not to use the correct units even though you know better.?
 
740GLE said:
So why can’t you just say 800whrs? You seem to be very adamant on using wrong units.

Cause when I get pulled over and the cop asked me how fast i’m going I don’t say 10 miles, you know my normal commute to work. He cares that I was doing 80mph in a school zone cause I was late ?

Back to your original question

What’s you decide 24v or 12v?
Click to expand...

Pretty sure that was self explained to start with. People tend to jockey to be the smartest person in the room they can't see the simple right in front of there face.
 

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Hogheavenfarm said:
Back to the op point - the reason 24v is mentioned is that the amp requirement will be reduced. A 600w inverter will be supplying a huge amp draw at 12v, thats the reasoning behind the limitations. Wire gauge size to the inverter will be 4/0 at 12v, but only 2/0 needed for 24v as the amperage draw is reduced by a factor of 2. This is cheaper wiring and less amps in the wire. At 600w you would be pulling 50amps, so maybe not a huge deal, but at 24v you would only be pulling 25. At 600w not really much of an issue, at 4000w it is.
Click to expand...

I get that but the actual load will never be over 210 watts if ever that high. So shouldn't that be about 18 amps? Also the inverter will be 16 inches max from the inverter so cable cost isn't really a problem. I won't need much.
 
Ronifer said:
What part of this didn't anyone understand?
Click to expand...
Everyone understood that what you meant was you would use 800 watt hours a day.

Then we tried to make sure you understood that watt and watt hour describe different things, because most people would only continue to use the incorrect term if they didn't understand the difference.
 
Ronifer said:
I get that but the actual load will never be over 210 watts if ever that high. So shouldn't that be about 18 amps? Also the inverter will be 16 inches max from the inverter so cable cost isn't really a problem. I won't need much.
Click to expand...
You should size wire for the maximum current the inverter can draw. I'm not sure where they are getting 4/0 wire from, that's huge for 50A . Most wire size calculators would say 6 or 8 awg for a short run.
 
if the surge is 1200w

Then that means it can draw a little over 100A on a 12v setup so wire should be sized and fused accordingly. Even if it will never be pushed to that limit.

I personally would go for 12v in your position. Some inverters might handle a small portion of your needs in sleep mode to help keep usage down ?
 
Reed Cole said:
You should size wire for the maximum current the inverter can draw. I'm not sure where they are getting 4/0 wire from, that's huge for 50A . Most wire size calculators would say 6 or 8 awg for a short run.
Click to expand...

Yeah I have a 12v 1500 continuous watt I take camping and use 4 awg and never have a problem running a 1200 watt coffee maker.
 
Reed Cole said:
Everyone understood that what you meant was you would use 800 watt hours a day.

Then we tried to make sure you understood that watt and watt hour describe different things, because most people would only continue to use the incorrect term if they didn't understand the difference.
Click to expand...

I can appreciate that but but I kept asking in my illustration wasn't it 800w use and they didn't seem to want to answer that. I very clearly stated the load 210 max and total watts I would use so it should have been understood I would think. Its basic algebra. 800w = (12 * 210w * 4 = 800wh)
In my statement and scenario 800w / 800wh is the same thing. It kept being said I was confused but rather they were confused. I don't know about anyone else but if I am confused I will say so but when I am not I will not say I am. ?
 
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