P1000 Trickle Charging Dual Batteries

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cattmann

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What @bumperm was trying to say was that a tender that only trickles half to 3/4 of an amp can keep the isolator connecting the batteries because you don't need a high amp charger to do that. It's about voltage.

What happens when you overcharge a battery? Best case scenario, you kill the battery. Worst case, the acid & water mix boil out, the battery swells and melts, hyrdogen builds up and it becomes a bomb waiting to

What @bumperm was trying to say was that a tender that only trickles half to 3/4 of an amp can keep the isolator connecting the batteries because you don't need a high amp charger to do that. It's about voltage.

What happens when you overcharge a battery? Best case scenario, you kill the battery. Worst case, the acid & water mix boil out, the battery swells and melts, hyrdogen builds up and it becomes a bomb waiting to go off.
Ok so I should check the voltage out put of all chargers to see if any will reach the voltage needed.
 
bumperm

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Ok so I should check the voltage out put of all chargers to see if any will reach the voltage needed.
Or you can see if the charger will get the blue light on the True isolator to turn on. This indicates that the battery being charged is at approximately 13.3 to 13.6 volts, high enough to share charging current through the True to charge the Aux battery. Most any good charger or battery maintainer should be adequate to do this.

If you have a 2nd battery, it's a good idea to have a dual voltmeter so you can easily monitor battery voltage. As I've posted before, I've installed a momentary push button switch to ground the dual voltmeters negative terminal, this switches the display on with no need to turn on the key.
 
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cattmann

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Or you can see if the charger will get the blue light on the True isolator to turn on. This indicates that the battery being charged is at approximately 13.3 to 13.6 volts, high enough to share charging current through the True to charge the Aux battery. Most any good charger or battery maintainer should be adequate to do this.

If you have a 2nd battery, it's a good idea to have a dual voltmeter so you can easily monitor battery voltage. As I've posted before, I've installed a momentary push button switch to ground the dual voltmeters negative terminal, this switches the display on with no need to turn on the key.
Yes I have dual volt meters.When I start my vehicle up it only takes aout 30 or 40 seconds for my true blue to light up.I watch my first voltage meter reading and you can tell when its going to light up.Even trickle charging my isolator lights up quickly.
 
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Even trickle charging my isolator lights up quickly.
Then you are good to go with that charger!

The only way you'll have issues would be if, for whatever reason, your primary gets drained down pretty low. Then it would take a sub 1 amp trickle charger an extended period of time to get it up to ~13.6V before it would connect the two batteries (blue light on) and start charging the AUX. Just give them regular TLC and you should be just fine. :)
 
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cattmann

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Then you are good to go with that charger!

The only way you'll have issues would be if, for whatever reason, your primary gets drained down pretty low. Then it would take a sub 1 amp trickle charger an extended period of time to get it up to ~13.6V before it would connect the two batteries (blue light on) and start charging the AUX. Just give them regular TLC and you should be just fine. :)
I left my 2amp /4amp charger on the 4 amp setting attached to my aux battery today and after a couple of hours the full charge light came on .So I now know that the 4amp charger will reach full charge on both batteries.I will try the .800 trickle charger at a later time and leave it on also to see what happens.
 
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cattmann

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Ok so I should check the voltage out put of all chargers to see if any will reach the voltage needed.
left my 4amp charger on the aux battery today for a while and it reached full charge status while the isolator was light up.Will try the .800 mA at a later time to see if it will do the same
 
Scoop

Scoop

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left my 4amp charger on the aux battery today for a while and it reached full charge status while the isolator was light up.Will try the .800 mA at a later time to see if it will do the same
Assuming all other features are the same between the two, the only appreciable difference is: How low is the battery when you START charging it and can the charger get that primary at/above ~13.6V. Do note that some chargers require a battery to be at a specific minimum voltage or it won't charge at all. Again, as long as you don't ignore your batteries, you should be GTG with just a sub 1A trickle charger that has a float mode.
 
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