First Top Charge
I finally got my volt/amp meter wired in to my Mega Watt and started my first Top Charge. Initial battery voltage was 13.2v. Mega Watt was set to 15v. Turn-on voltage was 14.8v @ 33a. It quickly went ...
Forum Discussion
You may indeed have started off with utterly fresh desulfated batteries. If specific gravity in all cells is 1.280 or whatever the batteries come with, then top charging the first time will freshen the lead sponge on the plate surface and do little else.
The more time a battery is correctly floated the fewer top charges it's going to need. Top charging is like taking mega-vitamins, you don't want to O.D. just because the bottle is sitting in the medicine chest. Or do equalizations which would be like taking prophylactic doses of an antibiotic.
Use a hydrometer correctly! It is a valuable instrument!. Keep a chart. Dip all twelve cells! Note the date. Do it again in a month. If all cells remain at 1.280 you needn't do a thing. If the battery is on float and specific gravity in all cells, falls from say 1.280 to 1.275 while being floated, the batteries are most probably slowly stratifying the acid. Do a top charge to mix the acid and freshen the plates. Again, this is with the batteries being floated.
If one or more cells drops in gravity faster than the others, I nick-named them "weak-sisters". Use a marker pen and note on the lid next to the cap 1, 2, etc. so you can remember which cells to dip first. If they start out weaker they will stay weaker for the entire life of the battery. They are the "go-to" cells when dipping. If the cells check good, forget the rest. A full dip should only need to be done every third month.
In the specific case of using the Mega on 4 golf-car batteries, time needed to do a top charge is going to vary throughout the life cycle of the batteries and how deeply cycled they get. Heavily cycled batteries will start to have unequal cell gravities a lot sooner and a lot more pronounced than lightly cycled batteries. Really heavy cycling may incur need for top charging every 7-10 days.
It is impossible for plates to sulfate without acid specific gravity not dropping. Sulfuric acid is the component that makes sulfation. So if specific gravity is full density in all cells, two things are evident a) No residual sulfation has formed on any of of the plates and b) the acid has not stratified.
After a month or two of occasional cycling your cells will take on personalities. You are looking for the the "Weak Sister" cell. It will be your go-to-first cell throughout the life of the battery bank. My bank of 24 cells has several weak sisters after 22 years. I always pick on the weakest. When it has lost .005 points the other 23 cells get zapped with a top charge as well. I had to hire Robles and his damned backhoe to move the weak sister cell closest to the door of the battery shed. The Freas is hanging just above it. You should do the same - make the weak sister cell battery the easiest to get to.
Using Trends & Tendencies, I know how long to set the timer for according to how much gravity the weak sister cell has lost. A loss of X amount of density means a setting of X minutes on the timer. When I hear the generator cough I know the cycle is complete, and I also use a pocket timer that screams at me.
But I do NOT top charge batteries that exhibit full specific gravity. That is a waste of time and energy, and yes it is harmful to perfectly innocent plates. The mild 15 volt setting means 15 volts would have to be applied for a long period of time to genuinely hurt a good battery, so an hour or two extra time per top charge is not destructive but I try and tweak the timer even more accurately.
The amount of time expended writing this took up more time than dipping the weak sister cell, starting the generator and twisting the intermatic knob and repeating ten times. Top charging becomes intuitive. My bank needs it every 13 - 16 days, because like me, it is old and infirm. When it was new, when dinosaurs roamed the earth, I could go a month to a month and a half between top charges.
Again, the idea of top charging is to dramatically reduce the need for full-on battery equalization which requires ten times of not more the amount of attention and energy that top charges require. Like the difference in expending energy to fetch the evening newspaper versus dropping and doing a hundred pushups.
And to repeat this point again, doing blind, automatic top charges is not intelligent. It is the specific gravity in the weak sister cell that calls the shots. When the shots become predictable elapsed time wise, graduate to the timer and verify once or twice, but you need dip ONLY the weak sister cell.
POOR QUALITY and FAILING batteries are difficult to maintain specific gravity at 100% despite attempts to charge them the normal way. This is the classic sign of a Mickey-Mouse grade new battery or a good battery that has grown gray whiskers. I'll make a statement to illustrate. Take a Rolls battery and compare it to an off brand warehouse big box battery the same BCI grade. The Rolls battery will require 1/5th the number of top charges the first year of operation of heavy cycling. Hell, the Rolls may require 1/10th or less. The differential is discouraging to those in the know. Lesser batteries are like spoiled brats, they need to be lorded over and slapped around and frankly I have neither the time nor the interest to waste. The philosophy and illogical thinking of "Gee I buy tires for ten dollars each and get a whole 5,000 miles on them, and I only need to air them up twice a week" escapes me.
Battery maintenance should be a piece-of-cake, occupying maybe <1% of the time in a camper's routine day. It takes me less than a hour a week to manage a ten ton battery bank and I would scowl if it took more...
The more time a battery is correctly floated the fewer top charges it's going to need. Top charging is like taking mega-vitamins, you don't want to O.D. just because the bottle is sitting in the medicine chest. Or do equalizations which would be like taking prophylactic doses of an antibiotic.
Use a hydrometer correctly! It is a valuable instrument!. Keep a chart. Dip all twelve cells! Note the date. Do it again in a month. If all cells remain at 1.280 you needn't do a thing. If the battery is on float and specific gravity in all cells, falls from say 1.280 to 1.275 while being floated, the batteries are most probably slowly stratifying the acid. Do a top charge to mix the acid and freshen the plates. Again, this is with the batteries being floated.
If one or more cells drops in gravity faster than the others, I nick-named them "weak-sisters". Use a marker pen and note on the lid next to the cap 1, 2, etc. so you can remember which cells to dip first. If they start out weaker they will stay weaker for the entire life of the battery. They are the "go-to" cells when dipping. If the cells check good, forget the rest. A full dip should only need to be done every third month.
In the specific case of using the Mega on 4 golf-car batteries, time needed to do a top charge is going to vary throughout the life cycle of the batteries and how deeply cycled they get. Heavily cycled batteries will start to have unequal cell gravities a lot sooner and a lot more pronounced than lightly cycled batteries. Really heavy cycling may incur need for top charging every 7-10 days.
It is impossible for plates to sulfate without acid specific gravity not dropping. Sulfuric acid is the component that makes sulfation. So if specific gravity is full density in all cells, two things are evident a) No residual sulfation has formed on any of of the plates and b) the acid has not stratified.
After a month or two of occasional cycling your cells will take on personalities. You are looking for the the "Weak Sister" cell. It will be your go-to-first cell throughout the life of the battery bank. My bank of 24 cells has several weak sisters after 22 years. I always pick on the weakest. When it has lost .005 points the other 23 cells get zapped with a top charge as well. I had to hire Robles and his damned backhoe to move the weak sister cell closest to the door of the battery shed. The Freas is hanging just above it. You should do the same - make the weak sister cell battery the easiest to get to.
Using Trends & Tendencies, I know how long to set the timer for according to how much gravity the weak sister cell has lost. A loss of X amount of density means a setting of X minutes on the timer. When I hear the generator cough I know the cycle is complete, and I also use a pocket timer that screams at me.
But I do NOT top charge batteries that exhibit full specific gravity. That is a waste of time and energy, and yes it is harmful to perfectly innocent plates. The mild 15 volt setting means 15 volts would have to be applied for a long period of time to genuinely hurt a good battery, so an hour or two extra time per top charge is not destructive but I try and tweak the timer even more accurately.
The amount of time expended writing this took up more time than dipping the weak sister cell, starting the generator and twisting the intermatic knob and repeating ten times. Top charging becomes intuitive. My bank needs it every 13 - 16 days, because like me, it is old and infirm. When it was new, when dinosaurs roamed the earth, I could go a month to a month and a half between top charges.
Again, the idea of top charging is to dramatically reduce the need for full-on battery equalization which requires ten times of not more the amount of attention and energy that top charges require. Like the difference in expending energy to fetch the evening newspaper versus dropping and doing a hundred pushups.
And to repeat this point again, doing blind, automatic top charges is not intelligent. It is the specific gravity in the weak sister cell that calls the shots. When the shots become predictable elapsed time wise, graduate to the timer and verify once or twice, but you need dip ONLY the weak sister cell.
POOR QUALITY and FAILING batteries are difficult to maintain specific gravity at 100% despite attempts to charge them the normal way. This is the classic sign of a Mickey-Mouse grade new battery or a good battery that has grown gray whiskers. I'll make a statement to illustrate. Take a Rolls battery and compare it to an off brand warehouse big box battery the same BCI grade. The Rolls battery will require 1/5th the number of top charges the first year of operation of heavy cycling. Hell, the Rolls may require 1/10th or less. The differential is discouraging to those in the know. Lesser batteries are like spoiled brats, they need to be lorded over and slapped around and frankly I have neither the time nor the interest to waste. The philosophy and illogical thinking of "Gee I buy tires for ten dollars each and get a whole 5,000 miles on them, and I only need to air them up twice a week" escapes me.
Battery maintenance should be a piece-of-cake, occupying maybe <1% of the time in a camper's routine day. It takes me less than a hour a week to manage a ten ton battery bank and I would scowl if it took more...
