WATTS = VOLTS X AMPS ????

[lbhsbz]

One thing that has not been mentioned are PCM controlled charging systems. I know many of the modernist Fords use what ford calls “smartcharge”. I’m not sure if this is used on stripped chassis or not, but it could certainly throw a wrench into things.

 

[2FORCEFULL]

FYI...for all reading, not to one person....it was told to me that the renogy 3000 watt inverter I have will shut down automatic before the battery gets to 100% discharge, and won't come back on untill the battery is at 12.8....

but here was my train of thought for the system I have right now... I kept it separate from the van as to not have drivabilty problems with the van..
heres how it works...or how I think it works...

first,... shore power, it's 30 amp... the 120v to the van is on a pig tail that gets plugged in a 30amp wall plug when shore is available,....if not, next best is the 2500 gen,,...and last, boondock, the pig tail gets plugged into the inverter,..(short times) and mostly small amp draws...tv, 700w micro. 1.2 amp fridge...
probley never run it again for A/C... but it's there...but if I decide to run the A/C off battery's ,.. I will put the 3000/9000 surge inverter and add 3 more battery's for a total of 800 ah...but I don't see that happening as I can do the same with starting the gen for about 5 bucks a day in fuel....


secound... charging the battery's...

i have a 300 watt solar,...
and, I hard wired one of these to the battery's .

LST Trickle Battery Charger Automatic Maintainer 6V 12V Smart Float Charger for Automotive Car Motorcycle Lawn Mower Tractor SLA ATV AGM GEL CELL Lead Acid Batterie

that I can un plug from the 120v power strip...so when gen is on or plugged to shore I can top of battery's if needed..I also have a led battery monitor that tells me volts and level of charge

 

[2FORCEFULL]

so here's where I'm at right now...

I bought one of these...

KeyLine Chargers 12V 140 Amp Dual Battery Isolator Voltage Sensitive Relay (VSR) Pro Dual Battery Kit
my idea is this,...if I ever do bomb the battery to 80 %..... I could turn the switch, let the van bring the battery up to float and shut if off...???????

with this switch, it won't allow the battery to pull more than 50a 's of charge....correct???? that saving the battery...???

T Tocas 50 A Circuit Breaker amp breakers with Switch Manual Reset for Boat Marine RV Yacht Battery Trailer Bus Truck, 12V - 72V DC, Waterproof (50A)

 

[2FORCEFULL]

also, I wanna add,.. the van is just sitting in the sun,..nothing on and the monitor says 14.4 volts and 100% battery,..my next test would be to turn on the fridge. and the inverter...probley be about a 1.2 amp draw @ 120v= 12 amp at 12v.....maybe get 6amps out of solar, so going 6ah in the hole when there is good sun...

guess I'll have to try to find out...but...I think the road is gonna be a short one...

 

[Uncle Dave]

On the trickle charger, make sure it holds the gel setting through a power outage.

You seem to have a good handle on whats going on. (way better than most guys)

You could try a 50 amp breaker in the mix and see what happens - its cheap enough.

I think your "modus operandi" as described in post 152 is workable.

 

[2FORCEFULL]

OK, here's the test,... @8:15 I turned the inverter on, and the fridge....the fridge was hot inside 87 degrees as was the temp inside the van

the battery @ 14.4, that dropped to 13.9 with the fridge on...

so the real test will be a reading some what hourly...and where it's at at sun down..vs 5am tomorrow...

 

[mesquito_creek]

What type Fridge do you have? Does fridge amp draw vary with conditions or does a fridge draw a consistent amperage regardless of the ambient temp or the temp of the contents?

 

[2FORCEFULL]

30 min check finds the battery @12.9 volts....hopefull that once the inside of the fridge cools to operating temp, the amp draw allows to bring the battery level up

 

[2FORCEFULL]

What type Fridge do you have? Does fridge amp draw vary with conditions or does a fridge draw a consistent amperage regardless of the ambient temp or the temp of the contents?

it's just a little rv fridge for an out door kitchen... I think I measured 1.2 amp draw...

 

[2FORCEFULL]

I checked the battery at 12:15....14.4, so full recovery , but, this morning I didn't notice , but the neighbors trees were shading my solar,... the real test will be to see how far it drops over night and if it will recover on it's own

 

[2FORCEFULL]

Update... went threw the night with inverter on, fridge on, microwave,and tv on stand by...@ 6 am battery was at 12.1 volts...so 50% discharge....we'll have to see how quick it recovers...but at this time you would wanna be making a pot of coffee.....so to be more off grid you would need the second 200ah battery

 

[mesquito_creek]

Update... went threw the night with inverter on, fridge on, microwave,and tv on stand by...@ 6 am battery was at 12.1 volts...so 50% discharge....we'll have to see how quick it recovers...but at this time you would wanna be making a pot of coffee.....so to be more off grid you would need the second 200ah battery

I would, or to be honest.. I DO run mine down past 12.v and use the storage I have. If that means replacing it more often then so be it. I look more at how many years it lasts vs cycles. I more batteries, more weight, more connections, more problems etc.. it’s not like you are full timing in this and pinching every dollar out of the one house battery. Probably will last you 3-5 years even if you punish the battery...

 

[2FORCEFULL]

So, rather than hook up to the gen for the short time needed to run coffee maker and toaster, If I do the isolater, i could just start the van, let it run while the coffee pot was on if the plan was to hit the road.... but,.. if staying, you'd have to run the gen....or run the van for a bit

 

[2FORCEFULL]

I would, or to be honest.. I DO run mine down past 12.v and use the storage I have. If that means replacing it more often then so be it. I look more at how many years it lasts vs cycles. I more batteries, more weight, more connections, more problems etc.. it’s not like you are full timing in this and pinching every dollar out of the one house battery. Probably will last you 3-5 years even if you punish the battery...

LOL, total with you,... what I do and what I post are separate, I try to keep the trolls on a diet..,... more what I've been doing is more mith buster and proof...like now... I know for fact that I can now run my fridge 24/7 with no problems and it will sustain

what I'm saying,... and I haven't tried yet,.... which I could right now is to see how much farter it will bring the battery down making a pot of coffee... I think I'll be fine,... and like said just kick the van on if needed..


ok, went out and put 8 cups of water in the coffee maker...turned it on, nothing,...volts stayed the same,...i figured it would have pulled it down a voly at least while it was running??? so hang tight.... coffee's brewing

 

[2FORCEFULL]

OK, done.... the volts dropped to 12.0 after about the 4 cup mark...but, before 5 cups... it went up to 12.9 volts...seems that even though the solar panel is 90% shaded by the neighbors trees,, it's still getting a charge....

 

[mesquito_creek]

LOL, total with you,... what I do and what I post are separate, I try to keep the trolls on a diet..,... more what I've been doing is more mith buster and proof...like now... I know for fact that I can now run my fridge 24/7 with no problems and it will sustain

what I'm saying,... and I haven't tried yet,.... which I could right now is to see how much farter it will bring the battery down making a pot of coffee... I think I'll be fine,... and like said just kick the van on if needed..


ok, went out and put 8 cups of water in the coffee maker...turned it on, nothing,...volts stayed the same,...i figured it would have pulled it down a voly at least while it was running??? so hang tight.... coffee's brewing

Good idea!... your battery might give up the surface charge and top end alot quicker on the morning reading at 12.1v and hold there for a long time in that lower 12v range. Bench racing vs actual observed behavior.

 

[mesquito_creek]

I would add the Renogy batter monitor into the system before I put more batteries on... That way you aren't using volts to measure storage and rather the Renogy battery sampling algorithms to display whats actually happening to the battery.

 

[Uncle Dave]

I would, or to be honest.. I DO run mine down past 12.v and use the storage I have. If that means replacing it more often then so be it. I look more at how many years it lasts vs cycles. I more batteries, more weight, more connections, more problems etc.. it’s not like you are full timing in this and pinching every dollar out of the one house battery. Probably will last you 3-5 years even if you punish the battery...

If the manufacturer is to be trusted, and if Steves result is the same every cycle - he'll get 750 days use out of that battery - thats 2 years.

200 bones a year at 399 dollars.

This is ignoring fall/winter which produce less sunlight, or any cloudy days he may have that dont get him back to float by end of day.

Its also ignoring the batteries gradual performance degradation over time which will make it harder to get back to float....

at 50% - he's right on the edge of this thing,

 

[mesquito_creek]

If the manufacturer is to be trusted, and if Steves result is the same every cycle - he'll get 750 days use out of that battery - thats 2 years.

200 bones a year at 399 dollars.

This is ignoring fall/winter which produce less sunlight, or any cloudy days he may have that dont get him back to float by end of day.

Its also ignoring the batteries gradual performance degradation over time which will make it harder to get back to float....

at 50% - he's right on the edge of this thing,

Isn't that 750 days of use where he cycles it? I figure with the fleet of RVs he has this camper gets used a couple dozen time a year and sits in storage on a maintenance charge for months at a time? ... But I fully agree if this RV is being used and cycled daily for months at a time. I might have made incorrect assumptions about use and frequency... and figured all this was actually just a pre-cursor to the soon to be "for sale" thread!

 

[Uncle Dave]

Isn't that 750 days of use where he cycles it? I figure with the fleet of RVs he has this camper gets used a couple dozen time a year and sits in storage on a maintenance charge for months at a time? ... But I fully agree if this RV is being used and cycled daily for months at a time. I might have made incorrect assumptions about use and frequency... and figured all this was actually just a pre-cursor to the soon to be "for sale" thread!

Correct - when I say a "day of use" I mean offgrid unplugged unassisted.

If its in his garage/driveway plugged in effectively no or very shallow cycling occurs.

If he takes it off-road for three months it appears it can operate autonomously in the fridge department and if he's there he can always start the genset.

If there is a freezer in that fridge Id definitely use the penny on frozen water method.