House battery and started battery with solar confusion

[jasona]

I built out my shell model and did all my electrical myself. It’s a pretty basic system and everything runs off 12v. When plugged into shore power or generator I have a onboard 6amp charger that recharged the battery. I’m looking to add solar with a smart charger that will allow me to monitor the system showing my usage and input. I basically will have 3 ways of charging the battery after the install, off the trucks alternator via a battery doctor seperator, shore power, or solar. Which leaves me with two questions.
Will the victron smart charger 15/75 input be thrown off by the other two charging methods?
Will my battery or solar charger be effected by introducing another battery when the truck is started and basically puts the house and sarter battery in parallel? I was under the impression that the two battery need to be the same and should have the same voltage. They are obviously both 12v batteries but one might by at 12.2 while the other is at 12.7. Thanks for any help and if this has been discussed in another forum sorry in advance please just direct me to that forum.

 

[rando]

You will need two devices to accomplish what you want - a solar panel and charge controller AND a battery monitor. The Victron 15/75 is a great choice for the charge controller, and I would recommend the 'smart' version with bluetooth built in. The app will tell you what is going on with solar (power in, and power out if you hook up the load terminals), but it won't know about power from your truck or onboard charger. To get the complete picture (solar + truck alternator + on board charger - loads) you need a battery monitor. The Victron BMV-712 Smart is the go to battery monitor of the moment.

There is no problem running multiple charging sources in parallel, they will all play well together.

 

[wyocoyote]

I have been led to believe that if charging a house and starting battery from th alternator they should be the same type volatage brand date of manufacture etc. if its just "in parallel" lie a two batt starting system that also you use for the house. If its a true aux house battery with its own charge controller off the alternator, you can have say a deep cycle. ( perhaps the batt doctor separator does this?) That victron w/ bluetooth sounds nice.

 

[jasona]

I have been led to believe that if charging a house and starting battery from th alternator they should be the same type volatage brand date of manufacture etc. if its just "in parallel" lie a two batt starting system that also you use for the house. If its a true aux house battery with its own charge controller off the alternator, you can have say a deep cycle. ( perhaps the batt doctor separator does this?) That victron w/ bluetooth sounds nice.

Thanks for the response. It is a true aux house battery but I don’t have a separate charge controller off the altinator. This is the batt doc I’m using https://www.wirthco.com/batteryisolatorseries.html
Is the isolator doing what I need to do to protect my batteries?

 

[ntsqd]

Pretty much, yes it is.

Could the house charging from the alternator be "smarter"? Yes, it could.

Does it need to be? I'm not convinced. It certainly does if you're trying to squeak the very last minute of life out of the house battery, but if you just want to have some power when camping and don't mind a slightly shortened battery life then I wouldn't worry about it. I have found that here on the Lower Left Coast's coastal desert that our solar system keeps the house batteries fully charged all of the time that the camper sits, and most of the time that we're using it. I would guess that the alternator now only does about 10% of the house battery charging.

 

[rando]

There maybe some slight advantage to running a DC-DC charge for the house battery off the alternator which is customized to that battery. However practically speaking, using an charge isolator relay like the one you have is standard practice and is what 99% of folks here are doing with no issues. You certainly don't need to run matched batteries, and no one does this as you want a deep cycle battery for the house, and a cranking battery for the truck.

 

[RandyP]

I would recommend a RedArc BCDC1240D battery charger. I have been using a BCDC1240 for more than 5 years with two Lifepro 125 AH batteries in parallel in a Hawk 4Wheel camper, Two 160 watt solar cells, and a 2005 ford superduty electrical system with two 12v sears platinum batteries (Odessey cloans). The alternator is a National 275 amp upgrade. Shore power thru IOTA converter/charger. Monitored by Bogart Engineering TM-2030 battery monitor. loads include a propane heater with fan, two exhaust fans, 12v refrigerator, water pump, led lights, Small Suresine inverter.
Works very well.