Unless this is for a portable system, for hiking or bike riding where weight and backwoods electrical generation are a prime consideration, Then consider adding a solar panel to your vehicles 12v System, and using a 12v charger which can cover a wide range of batteries.
My Nitecore I4v2 can do AA or AAA NIMH and 14500 or 18650 Li ion cells, and can work off of a 12v input.
Hardly the best charger available but under 20$ and can cover all my cylindrical battery needs.
For portable USB power, they have many packs which take 18650 cells
I use a single cell USB charger under 4$ that takes an 18650 cell. I have over a dozen I salvaged from old laptop batteries. These cells are not high capacity cells, but they have usable capacity left, and I have some quality 3400mah Panasonic cells I bought which are worth more than 2 laptop extracted cells in capacity.
Some ostriches like to have company when they bury their head in the sand and spout their muffled 'Gospel', and an ever changing battery longevity claims.
I used a PD9245 off of grid power and I liked it. No experience with using it on a generator. Bulk amps started at 46 and tapered to the 40 range until Absorption voltage was neared.
It did not always start out in bulk, when it goes to maximum output until 14.4v is neared. Mine was actually 14.56v. Most Often it would choose 13.6, actual 13.73. and my wiring circuit was short and fat.
I never actually saw it drop to 13.2 float automatically, I had to force it and it was actually 13.34v.
So In my experience the PD Converter needed manual control anyway, which I like, which is why i liked it. But I'd not choose it for personal use, as I know batteries sometimes need massaging with higher voltages, and the PD's or any other standard converter can't do it.
AGMs like LifeLine do not have the super high CCA ratings of Northstar or Odyssey AGM's, but the ratings are still quite high.
The ability to frequently and fully charge an AGM is paramount for its lifespan. It still takes hours to top charge them to full, but most AGMS can accept higher amps in bulk. But since you have a PD9260, any two batteries depleted could max that unit out.
I am impressed with my group 27 Northstar AGM. 930CCA, 90AH. When I take 45 AH from it at a rate higher than it established that 90AH capacity rating, voltage rebounds to over 12.2v, leading me to believe this battery is underrated in capacity.
It will be 2 years old next month, and have about 200 deep Cycles on it. Right now at ~ 180 deep cycles, It still rebounds to over 12.2v with 45AH removed from it, and can still easily start my engine depleted to below 50%.
My opinion is Lifeline make the best deep cycle AGM. I'd have no issues using one as a Starting/ dual purpose battery.
AGMS really do not like patial state of charge cycling, so you might have to press that button on the Pendant to hold 14.4v for another 4 hours.
Full charge is when amps taper to 0.5% of capacity at 14.4v at 77F. Recharge to here every cycle and it will be the best battery you ever owned.
Treat it like a red headed step child and it will become a very effective paperweight just as quickly as the cheapest AGM available in the same usage
A lot of us refuse to swallow the Smart charger Kool aide, and use an adjustable voltage power supply to achieve the voltage we desire for the duration our tools tell us is necessary to actually fully charge a battery
I use mine as a COnverter, bulk charger and top charger and equalizer, but there is nothing automatic about it. I have to lower the voltage or shut it off, or risk overcharging.
Mine is capable of 40 amps, and has a voltage range of 13.12 to 19.23 volts.
There is a Megawatt which is less expensive but it tops out in the 15.4v range. Unmodified, these require fine adjustments of voltage with a jewelers screwdriver, but you can set it to 15.3v unloaded, hook it up and take hydrometer readings every 15 minutes. you can also use it whenever your boondocker decides to drop to 13.8v when the batteries still desire 2 to 3 more hours at 14.4-8v.
Again, these are Manual chargers and they must have a human with a brain determine , or remember, to turn it off, or lower the voltage to a safe float voltage.
When run flat out at full output power, more heat dissipation is required, but for top charging it will hardly break a sweat on a single 12v flooded battery
I had a Norcold DE-0040. 1.7 cubic feet. It lasted about 5 years
I now have a Vitrifrigo c51is that is 3 years old.
Both had/have extra insultion and added ventilation to cooling unit and to interior.
The VF is much much quieter, and slightly more efficient, and more ergonomic. Not much more inside space, but it is better utilized.
The cooling unit was assembled nicely, and can be refilled. It has a radiator style condenser with a 120MM fan.
My Norcold failed due to low refrigerant levels and it was not refillable.
It had a passive condenser and the sawafuji compressor which would vibrate my whole Van. I expended much effort in trying to isolate fridge to reduce noise and vibration, with success, but not enough.
The VF needed no such modifications to dampen noise or vibration.
So there is my opinion having owned both brands. VF all the way.
The Dometic cycling on and off quickly could be entirely weak undercharged sulfated batteries triggering the low voltage disconnect of the Danfoss compressor controller.
Combine that with too long and too thin wiring and the fridge might be perfectly operational, it is just the battery and the wiring from it to fridge which is severely lacking.
Most people have no idea it is bad to leave a Lead Acid battery sit in a discharged state. Many think all they have to do is drive for 15 minutes and the battery is magically restored to full charge and 100% health, when nothing can be further from the truth
Has a thermometer to tell you how much to add or subtract from the float reading to compensate for temperature.
Make sure no bubbles stick to the float as it will then read high.
12v compressor fridges that use the Danfoss/Secop BD35f compressor, are very intolerant of too thin of wiring from battery to compressor controller.
If one is using a chest style with a Ciggy plug connector, Bypass these horrid connectors and get the wire closer and shorter and fatter to the battery.
Danfoss BD35f spec sheet indicates to use much thicker wiring than one would assume is needed for a compressor that cannot draw more than 6.5 amps at maximum rpm, not including start up surge.
They do not even say anything thinner than 12AWG is acceptable, no matter how short the distance might be.
The Ciggy plug cords provided with the chest style portable 12v units are 16awg perhaps 18awg on some. This is an insult to your compressor, and in direct contradiction to the Compressor manufacturer's instructions on how to wire it for power.
When I have run a 10 foot 12awg extension cord to my Vitrifrigo, and battery voltage dropped to 12.4, the compressor would not start. Only the condenser fan would kick on.
Wire them thickly, eliminate the ciggy plug. Voltage drop is the enemy. Disregard ampacity charts, and go for thick copper for minimal voltage drop.
I think Dometic is now employing Waeco's newer compressor which appears similar in design to the Danfoss/Secop bd35f.
My 1.8 cubic foot Vitrifrigo c51is performs beautifully, But I have added extra insulation to box and cabinet housing and a very well ventilated cooling unit that cannot recycle air itself has heated, as well as an interior fan.
Rare that mine consumes more than 1AH per hour or more than 24 in 24 hours
The Truckfridge TF49 and the Vitrifrigo C51is are very similar in design. The VF is assembled in Italy, the TF in China.
I spent 100$ more on a VF and am glad I did. The TF would not have allowed me to upgrade the condenser fan.
Here is a 4.2 cubic foot Truckfridge:
The powermaxes, once they get the battery to 14.6v, assuming short thick wiring, drop to 13.x something or other and the 85% to 100% stage takes probably 24 hours or more.
The PD9245 might not do Trojan's recommended 14.8v, but it will hold 14.4v for 4 hours when asked to do so. With the PM, one is powerless to hold higher voltages when desirable.
If generator charging day after day is in your schedule, the 4 hours of PD's 14.4v will return the battery to a higher SOC than the PM's 14.6v, and battery capacity will walk down less fast.
As far as combining with other charging sources, Once the battery voltage gets to the maximum abosrption voltage of one device, it will drop out as the other takes over and raises the battery voltage to its maximum.
Yes charging sources can confuse each other when batteries get in the 80% charged range or higher, but usually work together well below that state of charge.
West systems epoxy have fallen behind the times. Lots of blush, yellowing, secondary bonding issues, hard ratio to mix accurately, but granted not much of an issue in the OP's requirements
My Favorite epoxy is System3, the SB112 and Clearcoat resins for laminating fiberglass cloth onto wood. Have not tried their new silvertip resin.
They have various rot fix products too.
Their clear coat resin is pretty thin stuff, and cures very slow, Good for when a bunch of epoxy cures in a thick mass.
Epoxy creates its own heat so if a large mass is to cure, it can generate too much heat and expand, then shrink afterwards and compromise the bond.
And for reference my 1.8 cubic foot 12v Vitrifrigo c51is draws ~32 watts and has a 25% duty cycle or less in 80F ambient.
BUt I do have extra insulation.
My PSW inverter draws 0.24 amps turned on powering nothing
My MSW inverter draws 0.72 amps turned on powering nothing
My MSW inverter turned on powering nothing draws more than my fridge does in an hour, 60% of the time.
BFL, you said before the truck battery was dropping to 12.2v when idling to do the inverter/charger thing. Sounds like you are robbing Peter to Pay Paul.
Peter being the partially charged and now unhappy engine starting battery.
While My alternator is has rather pathetic output at 525 hot idle, this does not mean yours will too. I understand that you need not do anything to continue with the inverter jumper cable charger method.
Your alternator well wired to the house bank, could easily outperform the inverter/charger method.
500 mA, 0.5a might not be enough to get a battery to a high enough voltage that it can be fully charged with specific gravity maxed out . Many of these 0.5a wall warts simply cannot get a battery higher than 13.7 or 8, especially if it is a larger somewhat sulfated battery, and even when unloaded if the voltage is 18 volts.
AGM batteries tend to require less amperage to be held at higher voltages.
10 to 13% is a recommended charge rate, when one has all the time needed to complete the charge from a plug in charging source. When one is charging from a generator, then one does not want to run the generator for 9 hours just to meet this 10 to 13% recommendation.
One can indeed blast a battery with higher amperages. it is better to blast a battery with high amperage to a higher state of charge than it is for the battery to begin the next discharge cycle at a lesser state of charge and possibly fall below 50% because one was trying to slow charge it with the 'recommended' rate.
IF you get a Megawatt and an Ammeter, with your curiosity, you will accomplish so much more than the masses who want a plug and play automatic source to flash them a soothing green light and then add a year to their battery life in each praising of their green light purveying product.
I regularly hit my former 12v flooded battery with a 50% rate, and got close to 500 Cycles from it. Held to 10 to 13% rate maximum I would have come nowhere near that as there was not enough time to complete the charge before the next discharge began.
Amps and volts are not separate entities. Voltage is electrical pressure . Not enough pressure between source and battery and the amps can't flow . Once the battery reaches absorption voltage, the amps required to hold absorption voltage become less and less as the battery absorbs the top end of the charge. This takes about 4 hours once absorption voltage has been reached at the battery terminals, but the actual time varies according to many factors.
So get a real hydrometer and see how high the Specific gravity, and Voltage gets with your wall wart. It might not have enough juice to do the job, no matter how long it is left plugged in.
Or it might. You will have to tell us.
Leave charger on until all cells are 1.275 or higher.
If the wall wart/charger cannot get the cells to 1.275, you need a bigger charger.
After the cells are 1.275, then the maintenance charger should be able to hold them there.
Obsessing over voltage is common but unhealthy. Battery voltage when charging or discharging is like throwing a rock at a rubber band and trying to guess the weight of the rock by how far the rubber band stretched.
Most people cannot even hit the rubber band, much less see how far it stretched, but call their method gospel anyway.
'Proper voltage to starting battery'
Heck, I doubt any vehicle ever achieves this. It is all a compromise. Fatter wire will just act as if the engine battery is more depleted than it is and allow more amps to flow to the battery that needs the juice.
The Inverter powering a charger is a 15% loss of efficiency on both conversions. The alternator has to work even harder to get the same juice into depleted house battery.
Alternator hot Idle speed amperage can be poor. Mine is not very capable at all at Hot idle of ~550 rpm, at about 32 amps. At 800rpm this shoots up to 65amps.
As such I never Idle only to recharge.
Sounds like yours is not much better at Idle speeds and fatter wire might do nothing to improve idle speed amperage. But bulking up the OEM charging circuit can't hurt.
See if the jumper cables on Alt(+) studs to engine battery makes any difference in idle speed voltage held when under inverter/charger load to depleted house battery.
When I wired my friend's powerwagon I ran the 2awg cables under the truck in split loom, with lots of cable clamps and Zip ties to secure them tightly.
I'd not do the Inverter/charger thing unless towing a travel trailer, and the vehicle's voltage regulator was a 13.7v clown.
The alternator is so capable at bulk charging, I choose to harvest All I can from it. I'm not much fussed if this shortens its life as I can swap it out in 15 minutes and it is just a reman with a lifetime warranty, but if it was a PITA to swap and 300$ I would think differently about maxing it out often.
Either that or run a fat parallel cable from Alternator(+) stud to engine battery (+).
A fatter engine to battery(-) ground is a good idea too.
Can you easily get a clamp on the ALT(+) stud? I'd fear it grounding out on something.
The issue is the same as a converter over thin long wiring.
Fatter cable from alternator to battery eliminates the stock alternator charging circuit, and also allows the voltage regulator to hold higher voltages for longer.
In my friend's power wagon with 160 amp alternator, I ran ~ 13 feet one way od 2awg to a lifeline gpl-31XT 125AH battery to ALT(+) stud. I used the battery(-) as it was wired with 4awg from the factory.
When depleted to 50% this battery sucked 100+ amps initially from the alternator, at idle. this tapered to 86 amps when the alternator heated up to 220 F.
I used a 500 amp winch connector:
The voltage your vehicles regulator allows will play a large part in the 70% + range.
My alternator has no issues delivering 60 amps plus at 800+ engine rpm, but sometimes it decides 13.7 is all that is required and only a fraction of that flows when 13.7 is all that is allowed