Forum Discussion
RoyB
Oct 28, 2013Explorer II
When charging todays deep cycle batteries the difference between BOOST CHARGE 14.4VDC and NORMAL MODE 13.6VDC is 0.8VDC. When you add in the standard voltage drop for the DIODE BASED Battery isolators which is 0.7VDC it sure messes up what what you are trying to do when charging a deep cycle battery in a quick three hour time frame..
In other words it would be hard to use BOOST MODE smart mode charging going through an battery isolator.
consider these times determined by Progressive Dynamics on the amount of time each of these charging voltages will take to re-charge a deep cycle battery
"Progressive Dynamics ran this test on the amount of time it took a PD9155 (55-amp) converter/charger set to three different output voltages to recharge a 125 AH (Amp Hour) battery after it was fully discharged to 10.5-volts.
14.4-VOLTS (Boost Mode) – Returned the battery to 90% of full charge in approximately 3-hours. The battery reached full charge in approximately 11 hours.
13.6-VOLTS (Normal Mode) – Required 40-hours to return the battery to 90% of full charge and 78-hours to reach full charge.
13.2-VOLTS (Storage Mode) – Required 60-hours to return the battery to 90% of full charge and 100-hours to reach full charge."
If your 14.4VDC battery charging voltages drops by the 0.7VDC voltage drop when using an DIODE BASED high current ISOLATOR it will take the times stated in the 13.6VDC test shown above to re-charge that battery. It will charge your second battery but certainly will not re-charge that battery in a three hour period of time.
What they use today is SMART RELAYs verses ISOLATORs which monitors the DC VOLTAGES and when the truck alternator goes to its BOOST CHARGE mode it switches in the extra battery to be charged. Or you can do all of this manually by just switching in the RELAY CONTACTOR...
Battery DIODE BASED ISOLATORs worked great in the past when standard start batteries were being used but not so good these days meeting the required DC CHARGING voltages for the deep cycle batteries.
just my two cents...
Roy Ken
In other words it would be hard to use BOOST MODE smart mode charging going through an battery isolator.
consider these times determined by Progressive Dynamics on the amount of time each of these charging voltages will take to re-charge a deep cycle battery
"Progressive Dynamics ran this test on the amount of time it took a PD9155 (55-amp) converter/charger set to three different output voltages to recharge a 125 AH (Amp Hour) battery after it was fully discharged to 10.5-volts.
14.4-VOLTS (Boost Mode) – Returned the battery to 90% of full charge in approximately 3-hours. The battery reached full charge in approximately 11 hours.
13.6-VOLTS (Normal Mode) – Required 40-hours to return the battery to 90% of full charge and 78-hours to reach full charge.
13.2-VOLTS (Storage Mode) – Required 60-hours to return the battery to 90% of full charge and 100-hours to reach full charge."
If your 14.4VDC battery charging voltages drops by the 0.7VDC voltage drop when using an DIODE BASED high current ISOLATOR it will take the times stated in the 13.6VDC test shown above to re-charge that battery. It will charge your second battery but certainly will not re-charge that battery in a three hour period of time.
What they use today is SMART RELAYs verses ISOLATORs which monitors the DC VOLTAGES and when the truck alternator goes to its BOOST CHARGE mode it switches in the extra battery to be charged. Or you can do all of this manually by just switching in the RELAY CONTACTOR...
Battery DIODE BASED ISOLATORs worked great in the past when standard start batteries were being used but not so good these days meeting the required DC CHARGING voltages for the deep cycle batteries.
just my two cents...
Roy Ken
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