JKFlipFlop wrote:
Ok, so I know the old style diode isolators have been around for ever and are still in use today.
Since they are diode based a .3-.6 volt loss is created and your batteries never get fully charged. Even a small voltage drop is significant because you shouldn't be discharging your battery below 60%-70%, and a battery at 10.5 is basically dead. So really your power range exist between 12-13V.
Another concern is that the new solid state isolators relay/solenoid isolators put in parallel your starter and aux bank when charging. If your deep cycle house battery is at 60%, and it gets bridged to your starter battery, you can get some serious current draw. over 100 amps. I don't know but I seriously doubt a deep cycle battery is meant to be dumped with 100+ amps, and not charged with a 3 stage profile.
In fact, I do not think an isolator exists that uses a 3 stage charge.
Thoughts?
You need to do a little more education gathering before condemning the relay based isolators and the charging of the deep cycle batteries, from the alternator, while driving.
First of all, you should have a good three stage charger for your normal battery charging needs. It is recommended by most all makers of deep cycle batteries that, if they are seriously depleted, you should recharge them using your multi stage charger, rather then expecting them to charge from the alternator while driving home, when ever possible.
With all that said, the higher voltage output, and high current producing capability, of the alternator is not the potential disaster you seem to think. Unless this is the only charging ever available to your batteries, and is done every day, all day, there isn't much danger of hurting anything.
The batteries will not be force fed the 100+ amps that you mentioned. A battery will only accept the amount of current that is needs to reach a full charge. The batteries control the current flow, NOT the alternator. While charging at the higher constant voltage is not optimum, it does little damage in the total scheme of events.
Again, the fact that the alternator CAN produce 100+ amps, when needed, it doesn't have any bearing on the batteries unless the voltage is excessively high.
