Couple of questions about DC-Dc charging
I've been thinking about adding a DC-DC charger now that I've added 400 amp hours of AGM batteries. There are lots of useful posts but I haven't run into a couple of things I'm curious about. One ...
Forum Discussion
A DC-DC charger provides two functions.
• Provides correct voltage for multi-step charging of different battery chemistries.
• Limit the maximum draw on the vehicle charging (alternator and battery) circuit will provide !
These are the exact reasons I am looking into a DC-DC charger. In looking back at the AGM specs it says the initial current for charging is 30 amps. With 4 batteries drawing 120 amps on the alternator it would fry it quickly I'd imagine. It also recommends up to 14.9 volts of incoming voltage. I have my inverter/converter set to 14.7. My solar charger seems to top out at about 14.4 volts when set to AGM. My alternator will put out about 14.2 volts when it's cool. If the life of my batteries are extended by the extra voltage "push" and my alternator is spared from burning out as quickly I think it's all worth doing. There is also the option of limiting the charger output to 20 amps for days when I know I have a lot of driving or when it's particularly hot outside.
Thanks for all the input.
• Provides correct voltage for multi-step charging of different battery chemistries.
• Limit the maximum draw on the vehicle charging (alternator and battery) circuit will provide !
These are the exact reasons I am looking into a DC-DC charger. In looking back at the AGM specs it says the initial current for charging is 30 amps. With 4 batteries drawing 120 amps on the alternator it would fry it quickly I'd imagine. It also recommends up to 14.9 volts of incoming voltage. I have my inverter/converter set to 14.7. My solar charger seems to top out at about 14.4 volts when set to AGM. My alternator will put out about 14.2 volts when it's cool. If the life of my batteries are extended by the extra voltage "push" and my alternator is spared from burning out as quickly I think it's all worth doing. There is also the option of limiting the charger output to 20 amps for days when I know I have a lot of driving or when it's particularly hot outside.
Thanks for all the input.
