Forum Discussion
MEXICOWANDERER
Nov 11, 2018Explorer
Let me use another analogy...
"Spending eight dollars in fuel to drive across town to save four dollars because of lower pump price".
Rather than -argue- a point I pen examples.
When I argued a point that spending a hundred dollars in generator fuel to save eight dollars in battery lifetime gain was foolish no one seemed to "get it"
What seems to be the difficulty in understanding this. So and so manufacturing recommends... Of course they do. Reducing battery charge rate WHEN ON PUBLIC POWER does improve battery life. But the cost of generator and fuel does nor enter into the calculation according to the manufacturer. They want to make their batteries look as good as possible.
If a battery is charged at a rate that does not increase temperature as measured at the battery terminals then the rate is not excessive. For example
With BFL13's AGM batteries, he keeps mentioning that the manufacturer recommends some stated amperage maximum. He misses the point. Apply 14.4 volts charge rate right off the bat. If the batteries accept 45 amps, if they accept 145 amps without heating then this "MAXIMUM ABSORBSION ACCEPTANCE RATE" will save generator run time WEAR OUT and FUEL COSTS like crazy. i.e. it would be foolish to adhere to battery manufacturer recommendations. They "ASSUME" battery replenishment would be via public power. Generator charging is thirty times or more costlier than public power.
I written this thirty times on this forum recommending to IGNORE UTTERLY manufacturer's public power recommendations for maximum charge rate if you would take the time and measure battery post temperature. Do it with your finger. If the post becomes warm on a mild day, reduce charge rate. But never exceed VOLTAGE charge limits. Should I encounter a poster who says "I have chosen to" then that's a different story.
"Spending eight dollars in fuel to drive across town to save four dollars because of lower pump price".
Rather than -argue- a point I pen examples.
When I argued a point that spending a hundred dollars in generator fuel to save eight dollars in battery lifetime gain was foolish no one seemed to "get it"
What seems to be the difficulty in understanding this. So and so manufacturing recommends... Of course they do. Reducing battery charge rate WHEN ON PUBLIC POWER does improve battery life. But the cost of generator and fuel does nor enter into the calculation according to the manufacturer. They want to make their batteries look as good as possible.
If a battery is charged at a rate that does not increase temperature as measured at the battery terminals then the rate is not excessive. For example
With BFL13's AGM batteries, he keeps mentioning that the manufacturer recommends some stated amperage maximum. He misses the point. Apply 14.4 volts charge rate right off the bat. If the batteries accept 45 amps, if they accept 145 amps without heating then this "MAXIMUM ABSORBSION ACCEPTANCE RATE" will save generator run time WEAR OUT and FUEL COSTS like crazy. i.e. it would be foolish to adhere to battery manufacturer recommendations. They "ASSUME" battery replenishment would be via public power. Generator charging is thirty times or more costlier than public power.
I written this thirty times on this forum recommending to IGNORE UTTERLY manufacturer's public power recommendations for maximum charge rate if you would take the time and measure battery post temperature. Do it with your finger. If the post becomes warm on a mild day, reduce charge rate. But never exceed VOLTAGE charge limits. Should I encounter a poster who says "I have chosen to" then that's a different story.
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