How much converter/charger is really needed?
I have a pair of NAPA 9824M Marine/RV batteries with a 20 hr rating of 79AH each, wired in parallel. Is there, really, any advantage in going from a 45 amp (PD4645V) converter/charger to a 55 amp (...
Forum Discussion
Except if you want to meet the 20% minimum charging rate on AGMs that Mex insists upon. A 45 amper is 20% of 225 AH. What if your bank is bigger than that?
That's like driving a KIA on the autobahn. Have good mirrors and good reflexes and make sure your life insurance is up to date.
The AGM minimum rate is there to assure against significant premature death. The maximum -recommended- charge rate is there to make the manufacturer look as good as possible. These knotheads get into ******ing contests at trade shows comparing -their- battery against say 5 competitors. "WE GET 1,190 CYCLES IF LIFE VERSUS 1,042 FOR THE COMPETITION!
Telecom has reps that attend trade shows and while the reps are suspicious of everything they do note cycle longevity.
When public power is available for my Rolls 2-volt cells, guess what? The Trace inverter does all the recharging at 120 amperes. When the Kubota is used the charge rate approaches 500 amperes. If I screw up and a hurricane is coming I throw the Lombardini online, kill the TRACE and jam almost 700 amps into the 22 cells. This is a plate-eater rate but it's the least of all evils. There is usually five thousand dollars worth of lobster at stake.
BFL the 20% rule works this way but idiot battery manufacturers do not explain it well.
If you apply recommended charging VOLTAGE to a depleted AGM battery it MUST deliver at least 20% of amp hour capacity. Maintaining the recommended voltage when the absorbsion rate forces amperage below 20% and the VOLTAGE is maintained at the recommended absorbsion rate it is perfectly fine all the way down to .5% of amp hour capacity.
My Rolls batteries are wet. I set an ambiguous voltage when starting out fresh. Ambient air temperature around 30c 86F.
I applied 15.00 volts to the terminals. 540 or so amps dependent on the state of charge.
When the cell gravity ramped up and the electrolyte began to bubble vigorously, I took at "hot" dip on all the cells. Compensated, I came up with a gravity result too low for the circumstances. I was over amping the batteries. I reduced constant voltage charge rate to 14.8. It cut almost 60 amps off the total charge rate. The temperature gain on the cells was also reduced.
The 4 cylinder Kubota engine was modified to operate at 1,200 RPM for the six pole KATO generator. Simply put it's a ten thousand dollar engine. Along with fuel cost, engine wearout is factored into generator cost per kWh. Balance that with battery longevity and fuel cost and a complete cost reality was made apparent despite the contrasting dichotomy. This is exactly why I specified .300" plate thickness batteries. It all is designed to produce rational kWh at minimum total cost. Every four dollar per gallon diesel that gets sucked through that engine gets squeezed for every cent it costs. Every charge cycle timewise is at a bare minimum to reduce generator -wearout- and squeeze every Aztec fart out of every centavo of fuel.
Generators do three things
Annoy
Produce electrical power
Eat money like it's going out of style.
Does anyone out there desire generator noise to nature?
Smile a wider smile as more twenty dollar bills are extracted from wallet or purse?
Whistle zippidty-do-dah as they push the front door open on a generator rebuiding shop?
When I am hauling five freshly filled drums of diesel back from a 56 mile fuel run I am not the happiest of campers. My wallet is light. The truck gets 12 mpg. Kiss 20 dollars down the drain. Wear and tear and it screwed up my Saturday.
So, "Let's let the generator run to save 4% (thick plate batteries)" is not high up on my top-20-tunes
That's like driving a KIA on the autobahn. Have good mirrors and good reflexes and make sure your life insurance is up to date.
The AGM minimum rate is there to assure against significant premature death. The maximum -recommended- charge rate is there to make the manufacturer look as good as possible. These knotheads get into ******ing contests at trade shows comparing -their- battery against say 5 competitors. "WE GET 1,190 CYCLES IF LIFE VERSUS 1,042 FOR THE COMPETITION!
Telecom has reps that attend trade shows and while the reps are suspicious of everything they do note cycle longevity.
When public power is available for my Rolls 2-volt cells, guess what? The Trace inverter does all the recharging at 120 amperes. When the Kubota is used the charge rate approaches 500 amperes. If I screw up and a hurricane is coming I throw the Lombardini online, kill the TRACE and jam almost 700 amps into the 22 cells. This is a plate-eater rate but it's the least of all evils. There is usually five thousand dollars worth of lobster at stake.
BFL the 20% rule works this way but idiot battery manufacturers do not explain it well.
If you apply recommended charging VOLTAGE to a depleted AGM battery it MUST deliver at least 20% of amp hour capacity. Maintaining the recommended voltage when the absorbsion rate forces amperage below 20% and the VOLTAGE is maintained at the recommended absorbsion rate it is perfectly fine all the way down to .5% of amp hour capacity.
My Rolls batteries are wet. I set an ambiguous voltage when starting out fresh. Ambient air temperature around 30c 86F.
I applied 15.00 volts to the terminals. 540 or so amps dependent on the state of charge.
When the cell gravity ramped up and the electrolyte began to bubble vigorously, I took at "hot" dip on all the cells. Compensated, I came up with a gravity result too low for the circumstances. I was over amping the batteries. I reduced constant voltage charge rate to 14.8. It cut almost 60 amps off the total charge rate. The temperature gain on the cells was also reduced.
The 4 cylinder Kubota engine was modified to operate at 1,200 RPM for the six pole KATO generator. Simply put it's a ten thousand dollar engine. Along with fuel cost, engine wearout is factored into generator cost per kWh. Balance that with battery longevity and fuel cost and a complete cost reality was made apparent despite the contrasting dichotomy. This is exactly why I specified .300" plate thickness batteries. It all is designed to produce rational kWh at minimum total cost. Every four dollar per gallon diesel that gets sucked through that engine gets squeezed for every cent it costs. Every charge cycle timewise is at a bare minimum to reduce generator -wearout- and squeeze every Aztec fart out of every centavo of fuel.
Generators do three things
Annoy
Produce electrical power
Eat money like it's going out of style.
Does anyone out there desire generator noise to nature?
Smile a wider smile as more twenty dollar bills are extracted from wallet or purse?
Whistle zippidty-do-dah as they push the front door open on a generator rebuiding shop?
When I am hauling five freshly filled drums of diesel back from a 56 mile fuel run I am not the happiest of campers. My wallet is light. The truck gets 12 mpg. Kiss 20 dollars down the drain. Wear and tear and it screwed up my Saturday.
So, "Let's let the generator run to save 4% (thick plate batteries)" is not high up on my top-20-tunes
