So I bought 1800 watts of panels. . . now what?

[inetdog]

Also he said its prob a 9 or 10 seer system which in the 90's was a very high rating back then.

That makes a lot more sense. Would you care to apologize to Sunking?

Now his statement that it runs off Volt-Amps rather than watts has a glimmer of truth to it, but does not really make sense the way you describe it.

The A/C requires a certain number of watts, which will have to come out of the batteries via your inverter so you must know this number. A Kill-a-watt or similar meter could tell you this if there were a way to safely connect it to your A/C. But it also requires a significantly (for older units especially) larger number of volt-amps which will have to come from the inverter and have to be within its capacity too.

[cashaber]

Just to avoid any confusion on the part of those who are following this: BTUs are a unit of energy, like Kwh. The corresponding unit of power, which Sunking is referring to, is BTU/hour.

This is made even more confusing by the fact that a 4 ton AC designation is originally derived from the cooling produced by 4 tons of ice per hour.

So much for dimensional consistency. (Unlike most figures of merit, SEER was defined in a way which makes it dimensional. That means that a SEER of 1 does not hold any special place in the system.)

The AC guy came by today and confirmed my estimated wattage useage on my unit about 3900watts plus about 700 watts for the inside unit. he also stated that the unit doesnt run on watts (important of determining teh correct inverter to use in a solar system) and runs on amps which are 19. the voltage(197-240) also is a mid range and can use more or less depending on stress factors. Also he said its prob a 9 or 10 seer system which in the 90's was a very high rating back then.

[inetdog]

Once again it is a simple math formula Watts = BTU's / SEER. A 4-ton AC unit has a cooling capacity of 48,000 BTU's

Just to avoid any confusion on the part of those who are following this: BTUs are a unit of energy, like Kwh. The corresponding unit of power, which Sunking is referring to, is BTU/hour.

This is made even more confusing by the fact that a 4 ton AC designation is originally derived from the cooling produced by 4 tons of ice per hour.

So much for dimensional consistency. (Unlike most figures of merit, SEER was defined in a way which makes it dimensional. That means that a SEER of 1 does not hold any special place in the system.)

[cashaber]

Sounds like you have facts and numbers mixed up. A 4 Ton AC unit with an SEER of 22 uses 2200 watts, not 3300 or 3600. If it is indeed a 4 Ton unit and uses 3300 watts then the SEER has to be 14.5, or 13.6 if it uses 3600 watts. This is why you are getting into so much trouble here, your numbers do not add up. Once again it is a simple math formula Watts = BTU's / SEER. A 4-ton AC unit has a cooling capacity of 48,000 BTU's so 48,000 BTU's / 22 SEER = 2181 watts, round that up to 2200 watts or 2.2 Kw. If that AC unit ran 24 hours in 1 day it would consume 2200 watts x 24 hours = 52.8 Kwh. Hopefully it does not run 24 hours per day, more like 8 to 15 hours which puts your use around 17.6 Kwh to 33 Kwh range in a day.

Your electric bill does not tell you how much power (wattage) your AC unit uses. It tells you how much energy (watt hours) your house used in a specified amount of time.

To bad I dont have a 22 Seer TRANE

[Sunking]

cause the sticker on the side says so!!!!!!!!!!

Sounds like you have facts and numbers mixed up. A 4 Ton AC unit with an SEER of 22 uses 2200 watts, not 3300 or 3600. If it is indeed a 4 Ton unit and uses 3300 watts then the SEER has to be 14.5, or 13.6 if it uses 3600 watts. This is why you are getting into so much trouble here, your numbers do not add up. Once again it is a simple math formula Watts = BTU's / SEER. A 4-ton AC unit has a cooling capacity of 48,000 BTU's so 48,000 BTU's / 22 SEER = 2181 watts, round that up to 2200 watts or 2.2 Kw. If that AC unit ran 24 hours in 1 day it would consume 2200 watts x 24 hours = 52.8 Kwh. Hopefully it does not run 24 hours per day, more like 8 to 15 hours which puts your use around 17.6 Kwh to 33 Kwh range in a day.

Your electric bill does not tell you how much power (wattage) your AC unit uses. It tells you how much energy (watt hours) your house used in a specified amount of time.

[cashaber]

no i am not out of line because i know you do not know what you are talking about because you told me how much your ac unit uses and you do not even understand you did it. A 4-ton ac unit with an seer of 22 uses 48,000 btu's / 22 seer = 2181 watts, or we can just say about 2.2 kw.

cause the sticker on the side says so!!!!!!!!!!
And so does my elec bill

[Sunking]

opps I did it again I'm sorry so sorry.. my AC unit actually uses 3600 watts.. (This does not include my indoor blower) thanks for correcting my calculations which was +/- 10% error. ohh btw we only use 7kwh of elec/day w/ no AC... not 15 as stated above, I think I was thinking about something else.
anyways unless you know MY voltage & amps used by my AC YOU Sir are way outta line.


PS my AC is not a HUGE 22 seer TRANE hell it doesn't even say a seer rating on it. but it is a 4 ton AC
================================================== =======================

anyways this is really just an example

No I am not out of line because I know you do not know what you are talking about because you told me how much your AC unit uses and you do not even understand you did it. A 4-ton AC unit with an SEER of 22 uses 48,000 BTU's / 22 SEER = 2181 watts, or we can just say about 2.2 Kw.

[Sunking]

our AC went out and the last 24 hrs we used about 15kwh of elec, normally use about 30 - 43/day. that means our AC unit runs at about 3300 watts. .

I will ask you again. How did you determine your AC unit uses 3300 or 3600 watts?

[cashaber]

Did you measure the current to the AC unit with an amp clamp or did you just grab numbers from memory?

its listed on that sticker on the side of the unit


Amps 19
Volts 197 - 240

again amps x volts = watts of course thes can vary a bit depending on the actual volts pulled in actual running numbers they are a good ball park figure to estimate actual useage
=================================================


Again if you are hooked up to the grid and you have a 3500 watt inverter and your AC engages your inverter will not shut down the extra wattage will be pulled from the grid.
Remember though if the grid power goes off line so must your own grid must be turned or switched off automatically as to not feed the grid. you also do not need batteries to run a grid tie in system

[cashaber]

Also just to clarify. With my panels, I can get a 80 amp outback controller, wire 12V batteries to 24V, and use a 12v inverter? thanks

If you wire 12 volt batteries to 24 volts you will need a 24 volt inverter

[cashaber]

Again you are dead wrong and should not be giving advice because you have no idea what you are talking about.

omg get a life

found on Ebay

AIMS 1500 WATT PURE SINE WAVE 12 VOLT POWER INVERTER $357
AIMS 1500 Watt Pure Sine Wave Power Inverter 48 Volt $419
================================================== ============

Magnum MS4024PAE 120/240Vac 24Vdc 4000 watt Off-Grid inverter Pure Sine wave $1,750.00
SMA Sunny Island SI4248U Off Grid Inverter 4000 Watt 48 Volt DC $3,495.00
================================================== ===================
* items above are for reference only

these are just a couple examples of inverter costs. more power = more $$$ but voltage speaking your items
that run say on 12V at 100 watts may run at 80 or 90 watts at 24 or 48 volts.

if you cant afford the higher voltage 12 volt systems work just fine. Also FYI the big trucks on the road today 18 wheelers run of 12 volt systems just like your 4 cylinder car
they just have 4 batteries instead of 1. 12 volt systems are not a toy when it can shock you just as hard as a 48 volt system.

[russ]

Volts x amps = watts

Did you measure the current to the AC unit with an amp clamp or did you just grab numbers from memory?

[cashaber]

anyways unless you know MY voltage & amps used by my AC YOU Sir are way outta line.

Volts x amps = watts

[russ]

yes as stated above

Sunking asked how you came up with the number?

[cashaber]

How have you calculated this number?

yes as stated above