Charging two different battery banks simultaneously
Posted: Wed Jan 21, 2009 6:27 am
Al,
I looked into the docs because I have the same challenge here. The echo-charge is a voltage-follower, according to the manual. This means that the chargecontroller that supplies the charge, decides on the voltage that is supplied to the main battery based on the state of the main battery AND, through the echo-charge, supplies this voltage to the other battery as well. So the voltage supplied to both banks is always the same, which is far from ideal with two totally different battery banks.
I have a Xantrex Pathmaker (now not in use) which does basically the same as the Echo charge: connect both banks when the charge voltage supplied to one of the two banks is above a certain set point.
The advantage of the Pathmaker is that you can set the connect, disconnect and high voltage disconnect points yourself. So if you connect the alternator to the AGM house bank, which can be charged up to 14.9v, you can set the Pathmaker to disconnect the wet cell starter battery at 14.6v already. In this way you don't overcharge the wet cell.
See the charge characteristics of an AGM battery here: On the other hand, the much higher current (amps) that the AGM's can accept, will not be accepted by the small wet cell starter battery. Voltage and temp will rise quickly, perhaps disconnecting the charge source prematurely from the starter battery.
Another advantage of the Pathmaker is the high current connection; you can start your engine through a Pathmaker connection.
For you info I uploaded the manuals of the Echo-charge and Pathmaker here: NOTE: I have no interests in Xantrex.
--- In FreedomOwnersGroup@yahoogroups.com, "Al Lorman" <ajl@...> wrote:
>
> Alan:
>
>
>
> I've been considering installing an Echo Charge to control charging from an
> AGM house battery to a wet cell starting battery. The Echo Charge manual
> doesn't directly address this point. Do you have yours set up this way?
>
>
>
> Al Lorman
>
>
> That's the beauty of the echocharge. The alternator only runs to the house
> bank and does so directly (at least in my arrangement) not throught he
> switch. The starter battery is charged at up to 15A/H from the house bank
> controlled by the echocharge whenever the voltage of the start battery is
> below that of the house bank and at a rate dependent on the difference. I
> don't recall if it has a setting to allow to go from AGM house to Gel
> Starter at lower voltage but from AGM to wet cell as in your case is no
> issue.
>
> Alan
>
>
> I have a Freedom 15 (now Xantrex inverter charger with a second
> independently controlled charge output for the starter battery. That
> works fine when on the German dockline or running the generator. But
> perhaps that's enough and is there no need to charge the starter
> battery with the alternator.
>
> The problem always is to charge two completely different battery banks
> (one starter, 60Ah wet cell, four house, total 350Ah AGM)with one
> alternator regulator.
>
> --- In FreedomOwnersGroup@yahoogroups.com
> <mailto:FreedomOwnersGroup%40yahoogroups.com> , "Alan Kusinitz"
> <akusinitz@> wrote:
> >
> > Michel,
> >
> > For what its worth I currently use a Xantrex echocharge so my Starter
> > battery gets charged from the house battery. My shorepower charger is
> > connected to both banks but this isn't really necessary.
> >
> > Alan
I looked into the docs because I have the same challenge here. The echo-charge is a voltage-follower, according to the manual. This means that the chargecontroller that supplies the charge, decides on the voltage that is supplied to the main battery based on the state of the main battery AND, through the echo-charge, supplies this voltage to the other battery as well. So the voltage supplied to both banks is always the same, which is far from ideal with two totally different battery banks.
I have a Xantrex Pathmaker (now not in use) which does basically the same as the Echo charge: connect both banks when the charge voltage supplied to one of the two banks is above a certain set point.
The advantage of the Pathmaker is that you can set the connect, disconnect and high voltage disconnect points yourself. So if you connect the alternator to the AGM house bank, which can be charged up to 14.9v, you can set the Pathmaker to disconnect the wet cell starter battery at 14.6v already. In this way you don't overcharge the wet cell.
See the charge characteristics of an AGM battery here: On the other hand, the much higher current (amps) that the AGM's can accept, will not be accepted by the small wet cell starter battery. Voltage and temp will rise quickly, perhaps disconnecting the charge source prematurely from the starter battery.
Another advantage of the Pathmaker is the high current connection; you can start your engine through a Pathmaker connection.
For you info I uploaded the manuals of the Echo-charge and Pathmaker here: NOTE: I have no interests in Xantrex.
--- In FreedomOwnersGroup@yahoogroups.com, "Al Lorman" <ajl@...> wrote:
>
> Alan:
>
>
>
> I've been considering installing an Echo Charge to control charging from an
> AGM house battery to a wet cell starting battery. The Echo Charge manual
> doesn't directly address this point. Do you have yours set up this way?
>
>
>
> Al Lorman
>
>
> That's the beauty of the echocharge. The alternator only runs to the house
> bank and does so directly (at least in my arrangement) not throught he
> switch. The starter battery is charged at up to 15A/H from the house bank
> controlled by the echocharge whenever the voltage of the start battery is
> below that of the house bank and at a rate dependent on the difference. I
> don't recall if it has a setting to allow to go from AGM house to Gel
> Starter at lower voltage but from AGM to wet cell as in your case is no
> issue.
>
> Alan
>
>
> I have a Freedom 15 (now Xantrex inverter charger with a second
> independently controlled charge output for the starter battery. That
> works fine when on the German dockline or running the generator. But
> perhaps that's enough and is there no need to charge the starter
> battery with the alternator.
>
> The problem always is to charge two completely different battery banks
> (one starter, 60Ah wet cell, four house, total 350Ah AGM)with one
> alternator regulator.
>
> --- In FreedomOwnersGroup@yahoogroups.com
> <mailto:FreedomOwnersGroup%40yahoogroups.com> , "Alan Kusinitz"
> <akusinitz@> wrote:
> >
> > Michel,
> >
> > For what its worth I currently use a Xantrex echocharge so my Starter
> > battery gets charged from the house battery. My shorepower charger is
> > connected to both banks but this isn't really necessary.
> >
> > Alan