What is your Real Amp Hour per Day Usage

[StuM]

Originally Posted by chala

There is no need to be a brain surgeon to guess that this is about F deg. Or?

Not in that case. Degrees is the correct unit to use.

As for the scale, F is the only a feasible scale for 90° in this situation. It can be implied

However, it is better to make it a habit of always specifying.
What if he had said 33° ? Are we then considering about arctic or tropical conditions.

[StuM]

Originally Posted by chala

Good guess. One day you may learn not to pick on people for such a small thing. Be nice.

That's not such a small thing.

On a previous thread, a poster thought that he had a 500Ah battery because it was rated as 500 CCA (Cold Cranking Amps). (Can't recall the exact number, but it was about that).

His misapprehension was the result of exactly this regular confusion between Amps and Amp hours in discussions.

[newhaul]

Originally Posted by StuM

Sorry, but no you can't "count Amps".

Counting is determining the total number of something or group of things. It is done solely by addition or subtraction.
(you don't multiply or divide anything while counting).

If I am pulling 3 Amps the first time that I look at the ammeter and 5 Amps the second time that I look at the ammeter, I can't add them together and get 8 Amps or subtract one from the other and get 2 Amps,
both of those numbers are almost completely useless.
(Note for the other pedants around here, I said "almost")

However, if I make a note of the Amp hours shown the first time I look at an Amp hours counter and subtract that value from the reading when I look at it again later, then I know how many Amp hours I have used in that time.

I never said anything about an amp meter I simply said an hour meter which measures how long a piece of equipment has been running by measuring the simple fact that it is drawing power

[zboss]

Originally Posted by sailorboy1

That's a "new" frig? I have my large freezer and frig running all the time and wake up normally 20-40 ah out (depends on outside temps). Guess I never thought people had refrigeration that took over twice the power that mine takes.

You misunderstand.

Thats total for all consumables after the sun goes down.

Ours is a fridge/freezer. Its very efficient given that we only have one to three inches of of 27 year old insulation around the outside and 5 inches below!

65 Ah a night for about a 3.5 cuft freezer and the same size as a fridge... plus a 45 quart engel! We used to use close to 140 a night just for them!

[zboss]

Originally Posted by Sailmonkey

Just wait until you get to 90 deg water and 90 degree air....the fridge will run a lot!!!! More.

Your numbers closely match mine in Kemah Texas in the winter when the water is cold.


Sent from my iPhone using Cruisers Sailing Forum

Those ARE my summer power use! In fact, 100+ degree weather in Florida 80 degree+ water.

I'm pretty stoked about it.

[barnakiel]

He does not. Try again, use different imagery.

b.

[StuM]

Originally Posted by four winds

b., for me Ah / day is read as amp hours per day. But if someone is "grading papers" they might suggest it means Ah divided by days, and has said so, .. someone, can't remember who.

I think I would use the phrase Ah daily. And then hope some member would not ask in a sarcastic tone and whiny voice, "Does that mean 12 hours, 24 hours, a hop offshore, what?" hands on hip.

Anyway, nits can be picked, stay calm.

Ah per day, Ah divided by days and Ah daily are all equally valid ways of saying exactly the same thing (Ah/day). Take your pick.

[StuM]

Originally Posted by GoingWalkabout

Should I use a solar powered pump to spray/mist my panels to cool them down.

Probably would work. You are effectively creating a heat pump making use of the latent heat of evaporation of water. Electrical energy required to move the water will be far less than the heat energy removed from the panels.

[chala]

Originally Posted by chala

an average it is likely that never ever you may read 0.83A on the current meter.

Originally Posted by chris95040

What's a 100A battery? Do you mean 100 Amp hours? And what does "0.83A per each hour" mean? I think you mean "0.83A".

Honestly your own post proves my point, it was very difficult to understand what you were trying to say.

But if I excavate your point from under those errors , you are saying you could disambiguate my report by noting if my current draw was really 20AH / 24H = 0.83A, there would be no way for me to determine that, and therefore invalidates that as a possibility.

That would be possible only if
- i measured my consumption by periodically sampling a current meter
- that current meter only reported whole-number amp measurements

Of course, most folks determine their consumption with a tool that automatically accumulates your current draw over time and reports AH. And they certainly are not limited to whole-number amp measurements. But neither are any current meters that I've ever seen, either.

Sure it is difficult to understand for some and you did not understand it.
By the way in StuM spirit the correct unit is Ah.

[thinwater]

Originally Posted by StuM

Please use the correct units!

Keep us tight. Like spelling and grammar, mistakes happen, but disregard should be corrected. I've been corrected many times on spelling, grammar, and malapropisms, I didn't feel good about it, but learned something each time. I never said "you know what I mean," because they did, and I was still wrong.

-----

35-65AH/day at anchor, depending on the season. Use of fans, fridge, heater, and length of day matter.

50-80AH/day underway. Use of lights and autopilot varies (I don't feel the need to keep all the instruments on) and fans aren't needed.

I have 150 watts of solar; in the summer I'm over, and in the winter or with too much gray weather, I lose ground. I need to add a little more solar. As much as possible, I believe in getting up at dawn and going to bed when it is dark. Seems logical.

[StuM]

Originally Posted by Bulawayo

Stu, Can you suggest a good source for educating people on this subject. I am very happy to add to my knowledge if only I knew where to look.
I believe I understand already, but am probably not that well versed in expressing myself correctly in this field.
I have some older books on the subject so shall also have a look in them, meanwhile.
Thank you.

One place to start would be a thread that I initiated here:

http://www.cruisersforum.com/forums/...ml#post1933764

The initial post basically says it all. Unfortunately it digressed into a lot of unnecessary discussion as a result of a few people being reluctant to understand the points being made.

If you don't want to take my word for it, here's a couple of other resources:
kW and kWh Explained - Understand & Convert Between Power and Energy

https://en.wikipedia.org/wiki/Watt#C...watts_per_hour

These two refer mainly to Watt and Watt hour, rather than Amp and Amp hour, but the point is exactly the same. It's just that we generally assume 12V in the boating world, since that is the vast majority cases, and we tend to measure Amps rather than Watts.

(The fact that Amps in this case are pretty much the same as Watts only 12 time smaller makes the arithmetic a bit easier ).

When we start talking about 6V golf cart batteries in a system, however, things doget tricky for those who don't have a basic understanding of Watts, Amps and Wh, Ah. It's not uncommon to see major errors in calculation of power availability.

[four winds]

Originally Posted by StuM

Ah per day, Ah divided by days and Ah daily are all equally valid ways of saying exactly the same thing (Ah/day). Take your pick.

Well, son of a gun, and blow me down. That is certainly correct. I just didn't think of it that way. Specifically, substituting the number 1 for the word day. Makes the math work, cool.

I prefer speaking in words in conversation.

Since the opportunity presents itself, let met say I don't get bent about your efforts to clarify units. Good for you. I read the thread you started about the issues. And that's the place for prolonged tutelage.

Maybe in a thread like this a quick simple mention is in order and then back to the actual conversation, warts and all.

The prolonged sidetrack discussion is less than ideal. In don't think it adds value here. That other thread is a good place to take that dialog, or link to it.

I doubt you actually have any confusion about what is being intended when units are misused. Roll with it. Link to your tutor thread and then address the riddle presented here....here. That's just my suggestion.

This thread has obscured the OPs desire to get an idea of what folk's real usage might be. But not because someone used units incorrectly.

I gotta cook some bacon and eggs, or I would look back to see if you shared your usage with the OP. Wait, no I wouldnt. But if haven't you should. And invite others over for a lesson on your units thread.

[sailorchic34]

Originally Posted by StuM

Probably would work. You are effectively creating a heat pump making use of the latent heat of evaporation of water. Electrical energy required to move the water will be far less than the heat energy removed from the panels.

Well not really a heat pump (sorry Stu) as your not pumping, or rejecting heat from point A to point B. It's just a phase change to absorb heat as the water evaporates.

I might attach a absorption media (polyethylene open weave mat) to the back of the panel and run a tiny 12V pump to circulate sea water (assuming it's cooler then PV panel surface temperature) across the mat. Panel voltage is rated at standard conditions, which is 20 degrees C.

Typical panels loose about a volt per 20 degree C rise (roughly ball park). So if your using a MPPT controller you could gain some watts by cooling the panel. perhaps as much as 10-15 watts per panel. But you would have to subtract the power to run a pump. Those of us with only a PWM controller, it offers no advantage. Pity.

I might build a flat plate heat pipe (using copper plate, solder, long wicks and refrigerant (propane, R134A, etc) that could do a fair bit of heat rejection with no moving parts. Now that would be a heat pump, transferring heat via refrigerant phase change from one side of the heat pipe or heat plate to the other.

Sorry for the thread drift.

[weavis]

We have removed posts where language not becoming is included. This is an international board and children read the posts.

We will be cracking down on offensive posts from here on in. It is too time consuming to 'edit' posts so they will just be removed. If you notice that some of your posts are missing on this thread, you now know why...

MIND YOUR LANGUAGE!!! That includes words in common usage in English speech, but not acceptable on an international forum. Its not hard... if you think it might be deleted.... dont use...because it might be.

[four winds]

Thinwater, a respected member says keep up the fight. I agree, but,... take it outside, so to speak.

SailorChic, another respected member, joins the ruckus at the bar. And the OP is trying to ask the patrons at the bar what their favorite drink is.

I just hit the saloon doors to go cook some bacon. My horse looks annoyed anyway.