I have an Optima Yellowtop battery to power my laptop and fridge so I don't have to idle. It's connected to the engine battery so the engine batt charges the Yellowtop while I drive. There's an isolator between the two batts so the engine batt doesn't get drained while I'm parked. I've had to put in a new engine batt each of the last 2 winters, so I'm wondering if having to charge the Yellowtop shortens the life of the engine batt.
Battery question
- Thread starter vipra
- Start date
and yet another post about battery problems.
JMO and thats why I went with a Honda generator instead of battery power. Just too many little problems for me.
JMO and thats why I went with a Honda generator instead of battery power. Just too many little problems for me.
60MPH
Expert Expediter
what kind of isolator do you have if its just a solnoid when you turn the key on it links all the batteries in line, and yes when that low yellow top gets lined up with your start battery the system will try to equal out, and in turn will suck energy out of your start battery at a high rate "starting batteries are not made to be pulled down that far that fast and it will make you go thru batteries like you are now. Now if you have a real isolator and its wired up properly then the yellow top and your start are never hooked up inline so your start will not get the big draw, the only big draw it will get is from when you start your truck. I have 2 discover Agm's isolated from my 2 start batteries and never have had any problems. but with my old van I had 2 deep cycles wired thru a solnoid and I had the same problem you are having now. The minute you turn the key those batteries link up which is okay if they are all fully charged then you got ton's of starting power and no problems, But when you have sat for like 12 hours watching tv,using laptop,PS2 roof fan, espar or whatever them deep cycles are low. and one thing to remeber about electrity "IT ALL WAYS WANTS TO BE EQUAL" i.e. as in draining your start to make the voltage equal between your deep and start battereis which in turn kills your start battery and helps kill your alternator in a hurry. I am sure turtle will lend some info on this he knows alot about batteries and electrity.
60MPH
Expert Expediter
OVM I am with you on the honda 2000 I got 1 I use it from april to sept. for my rooftop air and for tv and what have you. But in the fall and winter time there's no need for a/c so I just use my deep cycles. I have found that in the fall and winter I can sit awhole weekend without starting the van on just my 2 discover advanced agm's and that includeds watching tv using the laptop,Ps2,roof van "to suck out cigar smoke",and listening to the xm radio. and running the espar half way on the dial the whole time. although last year I took a load to miami over holiday break and wish I had the gen because it was 75 and humid and I had to idle the truck and keep the windows up because of the mosiqutos, that's the only down fall that I have found with my set-up, It works for me and that's all that matters:+
theoldprof
Veteran Expediter
In my GMC van I had two Wally World boat batteries separated from the main batt with a solenoid. The solenoid was wired to my power window circuit. My windows were hot all the time. When the key is turned to start, the engine and all the related components are energized, but the window circuit is temporarily dead. So, when my engine is cranking and the aux batts may be dead, there was no surge of power from the engine batt to the aux batts. When the engine started and the key moved to the run or on position, then the solenoid was energized and the gen would charge the aux batts. Never had a prob. I also had a toggle switch I could energize the solenoid in case of main batt problems. Just in case.
:+ :+
:+ :+
60MPH
Expert Expediter
toggle switch, thats what I ended up doing on my old van I would keep the switch off until I got on the highway then I would flip it on when I got up to highway speed, because the alt is putting out good current at highway speeds not so much at idle. If any of ya'll got a solonid then I would install a toggle switch on the ign. source wire "thats one of the small wires on one of the small post on the solonid" thats only hot when the key is in the on pos. this will save your start batteries and will help save your alt. to. because when you are trying to charge a almost dead battery at idle you are really over workin the alt. and the vans electrical system. hopes this works for ya
p.s. never thought about using the pw circuit but I can see how it would work, but if you don't got pw's then try my method.
p.s. never thought about using the pw circuit but I can see how it would work, but if you don't got pw's then try my method.
I'll add more detail later when I get time, but for now, the yellow top and the blue tops are internally identical, no functional difference whatsoever. The only difference is marketing and the terminal connections.
Yellow top, blue top, both are combination deep cycle and starting (hybrids).
Slow and steady, even in expediting, wins the race - Aesop
Yellow top, blue top, both are combination deep cycle and starting (hybrids).
Slow and steady, even in expediting, wins the race - Aesop
As has been alluded to, when you have batteries of differing states of charge and/or capacities, the electrical energy in them will always try to be equal. In other words, if you have an older battery and you connect a newer battery to it, the older battery will feed off the new battery for its charge. As batteries age their capacities diminish. So, when you place a load on the batteries, the old battery will be drawn down faster than the new one (Peukert Effect) and will feed off the new one, making the new one work to both sustain the amp draw on the bank, as well as to feed the older battery at the same time. The end result is, the lifespan of the newer battery is dramatically reduced, and the end-of-time for the old battery is likewise dramatically accelerated. You're burning the candle at both ends.
Always replace batteries in a set, of the same manufacturer, type, capacity and date of manufacture - same lot if possible. Always start out with more batteries than you think you'll need, because you can't just add new batteries to old for the reasons outlined above. If you start out with 4 batteries and then 18 months or 2 years down the road you realize you need 6 batteries, you can't just add a couple of batteries. Instead, replace the older 4 batteries with 6 new ones.
As to the original poster (Vipra), make sure you have a true isolator and not a simple continuous duty solenoid. Second best option is a battery separator.
In the case of either a separator or an isolator, which combines the batteries into a single system so the alternator can charge them all at once, the charging requirements must be the same for the starter battery and the house battery.
For example, most starter batteries require constant amps (30 amps max, usually between 10-20) and variable voltage, while AGM deep cycle batteries require constant voltage and will handle variable amps. The voltage requirements of AGM's are vastly different from that of a cranking battery, so when you combine batteries via a battery separator or isolator, both batteries are gonna get the same charging voltage and amps. Ergo, both batteries had better have the same charging requirements.
So, with batteries combines and the key turned on and your running down the road and charging the batteries, whatever you're pulling from the house bank (fridge, whatever) is also pulling from the starter battery. Not to mention that the starter battery, which will recharge usually in a matter of minutes, will be subjected to the same charge (and hence, overcharge) as the house bank, whether it needs it or not. Also, when combined via the isolator or separator, even though both batteries are being charged by the alternator, the house bank is also pulling from the starting battery at the same time, putting further stresses on s starting battery.
The ideal solution is to use an external programmable voltage regulator (programmed for the charging requirements of the batteries you want to charge) and use the alternator and that regulator to connect directly to the house bank. Then, using something like a Xantrex Echo Charge or a Balmar Duo Charge (both of which are also programmable voltage regulators) you connect the house bank to the starter battery, thereby allowing each set of batteries to be fully charged and discharged independently.
Slow and steady, even in expediting, wins the race - Aesop
Always replace batteries in a set, of the same manufacturer, type, capacity and date of manufacture - same lot if possible. Always start out with more batteries than you think you'll need, because you can't just add new batteries to old for the reasons outlined above. If you start out with 4 batteries and then 18 months or 2 years down the road you realize you need 6 batteries, you can't just add a couple of batteries. Instead, replace the older 4 batteries with 6 new ones.
As to the original poster (Vipra), make sure you have a true isolator and not a simple continuous duty solenoid. Second best option is a battery separator.
In the case of either a separator or an isolator, which combines the batteries into a single system so the alternator can charge them all at once, the charging requirements must be the same for the starter battery and the house battery.
For example, most starter batteries require constant amps (30 amps max, usually between 10-20) and variable voltage, while AGM deep cycle batteries require constant voltage and will handle variable amps. The voltage requirements of AGM's are vastly different from that of a cranking battery, so when you combine batteries via a battery separator or isolator, both batteries are gonna get the same charging voltage and amps. Ergo, both batteries had better have the same charging requirements.
So, with batteries combines and the key turned on and your running down the road and charging the batteries, whatever you're pulling from the house bank (fridge, whatever) is also pulling from the starter battery. Not to mention that the starter battery, which will recharge usually in a matter of minutes, will be subjected to the same charge (and hence, overcharge) as the house bank, whether it needs it or not. Also, when combined via the isolator or separator, even though both batteries are being charged by the alternator, the house bank is also pulling from the starting battery at the same time, putting further stresses on s starting battery.
The ideal solution is to use an external programmable voltage regulator (programmed for the charging requirements of the batteries you want to charge) and use the alternator and that regulator to connect directly to the house bank. Then, using something like a Xantrex Echo Charge or a Balmar Duo Charge (both of which are also programmable voltage regulators) you connect the house bank to the starter battery, thereby allowing each set of batteries to be fully charged and discharged independently.
Slow and steady, even in expediting, wins the race - Aesop