I have a small riding mower that has the 3 amp charging system. The one with the diode molded into the output wire. I installed a voltmeter so I could monitor the charging system and I see the voltage go as high as 17 volts. After it gets hot it will go down to 15. Most lawn mower batteries are sealed so you can't add water. The battery would last longer if the voltage was lower so it wouldn't boil out the water. My question is has anyone used a regulator for a 5-9 amp system on a 3 amp? It only has 1 a/c lead and a battery lead. I'm sure it has to be bolted to ground so it can dump current when the voltage gets high. I was also just thinking of replacing the diode with a 14V Zener.
3 amp charging system.
- Thread starter kh0432
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Briggs doesn't list a voltage output for that charging system. Only how to test for amp output. I don't think they are worried about the voltage on that one. I see how 16-17 volts could be about normal on that system.
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Just replacing a diode with a zener diode isn't that simple. First the AC voltage must converted to DC with is what the diode does. Then a zener along a current limiting resistor can be between the output and ground. Then zener also need rated to the peak DC pulse voltage. What you are measuring is just the average DC. The peak voltage is actually up to 1.414 higher than the 17 vdc you are reading. The battery is acting as a capacitor so it resistance is lower when discharge hence the higher charging rate.
As the voltage readings you are find for a charging system such this Briggs.
bertsmobile1
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AFAIK you can use the regulator from the 5-9 amp alternator on your mower.
I seriously doubt it will make a tinkers curse of a difference to the battery.
Mower batteries have short lifes because they are flimsey mechanically not because of the rudementry electricial system.
The plates now days are 0.5mm thick and they can not take the vibrations & bashing that a mower puts out.
If you want to increase the life of your battery fit a better more robustly constructed one that is AGM & PVR.
However quality costs money and most ride on mower owners are too tight fisted to pay the extra.
They want the cheapest possible battery and that is what they get.
Cheap is never good value but we have all been subjected to decades of powerful advertising telling us the exact opposite till we now believe it.
I seriously doubt it will make a tinkers curse of a difference to the battery.
Mower batteries have short lifes because they are flimsey mechanically not because of the rudementry electricial system.
The plates now days are 0.5mm thick and they can not take the vibrations & bashing that a mower puts out.
If you want to increase the life of your battery fit a better more robustly constructed one that is AGM & PVR.
However quality costs money and most ride on mower owners are too tight fisted to pay the extra.
They want the cheapest possible battery and that is what they get.
Cheap is never good value but we have all been subjected to decades of powerful advertising telling us the exact opposite till we now believe it.
Mkala
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You can use an higher amp regulator as it normally has to clamp the voltage to 14.4V as cars do. I don't know exactly the construction of the briggs 5-9amp but as said above this should be fine for a basic application.
Mower batteries does not last long because they are cheap of course, but you can find some equivalents with better lifetime. Some AGM can last 5 to 10 years, but there are some conditions. First, most of simple engines have cheap charging systems too... as described here, a diode a just a strict minimum to make it works... Voltage regulation is welcome to avoid frying batteries. Last thing to do is to charge battery 2-3 times during winter. A battery that goes below 10.5V will never fully recover (yes they take charge, but low voltage makes sulfation that is never 100% reversible).
Mower batteries does not last long because they are cheap of course, but you can find some equivalents with better lifetime. Some AGM can last 5 to 10 years, but there are some conditions. First, most of simple engines have cheap charging systems too... as described here, a diode a just a strict minimum to make it works... Voltage regulation is welcome to avoid frying batteries. Last thing to do is to charge battery 2-3 times during winter. A battery that goes below 10.5V will never fully recover (yes they take charge, but low voltage makes sulfation that is never 100% reversible).
Well I had to try it. Regulator cost me $11.54 and it works fine. Voltage is now at a steady 14.1V. I'm sure there will be responses that this was a waste of time. I've been an automotive electrician for 40+ years and I just couldn't get used to seeing a charging system running that high. I guess it's a lot cheaper to use a 25 cent diode instead of a $5 regulator when you're making 100,000's engines. At least now I know I'm not cooking the battery.
Mkala
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For this price it is a good choice I think. Don't forget to charge the battery in the winter season and the regulator will pay itself on the first battery, it will last twice as long if not fried by charger and not depleted during winter.