Community Forums

dmacd · 12-12-2020, 11:15 AM

Quote:

Originally Posted by Phaselag

Make sure you check the specs/capabilities of the renogy combo charger's solar side and your panel. Typically the combo's are weaker on solar than the stand-alone solar chargers. You may be end up happier leaving the combo in the truck and adding a dedicated solar charge controller for your portable panel. Renogy makes several that are not expensive.

It's the DCC50s, so you can charge at 50 amps from either the solar or the alternator source, or it'll cap both sides to 25 amps if you're charging from both at the same time. Should be good enough until I commit to a full solar setup, will def split the chargers into separate units then.

Phaselag · 12-12-2020, 10:49 PM

Quote:

Originally Posted by dmacd

It's the DCC50s, so you can charge at 50 amps from either the solar or the alternator source, or it'll cap both sides to 25 amps if you're charging from both at the same time. Should be good enough until I commit to a full solar setup, will def split the chargers into separate units then.

The amp out should be ok, the problem may be the voltage. That combo has max 25 volts input for the solar. I believe you said you were using a 300 watt panel, which may exceed that voltage depending on how it is set up.

dmacd · 12-14-2020, 11:30 AM

Quote:

Originally Posted by Phaselag

The amp out should be ok, the problem may be the voltage. That combo has max 25 volts input for the solar. I believe you said you were using a 300 watt panel, which may exceed that voltage depending on how it is set up.

Yeah, but its a cheap piece of crap so I'm actually pretty shocked it output 240w during clear winter sun.

Should be fine for the first initial jump into full time life. Still debating on wether to spend the $$$ outright for a good solar setup, or drop that cash into the new f150 with the 7.2kwh power bank and idle a truck for a few hours a day instead. Solar setup is probably smarter but I'm an idiot who likes new toys.

On another topic, what are the benefits of doing a 24 or 48v battery bank rather than a 12v one? From what I'm reading, it lets you supply the power pull at a lower amperage, so if my inverter is supplying 100w my 12v bank would push 8.33a and a 24v bank would do the same at 4.16a.

If thats correct (and I have no idea really if it is), at what power requirement would it make a difference to do say a 200ah 24v bank versus a 400ah 12v one? Are there any other benefits?

jcussen · 12-14-2020, 11:48 AM

Quote:

Originally Posted by dmacd

Yeah, but its a cheap piece of crap so I'm actually pretty shocked it output 240w during clear winter sun.

Should be fine for the first initial jump into full time life. Still debating on wether to spend the $$$ outright for a good solar setup, or drop that cash into the new f150 with the 7.2kwh power bank and idle a truck for a few hours a day instead. Solar setup is probably smarter but I'm an idiot who likes new toys.

On another topic, what are the benefits of doing a 24 or 48v battery bank rather than a 12v one? From what I'm reading, it lets you supply the power pull at a lower amperage, so if my inverter is supplying 100w my 12v bank would push 8.33a and a 24v bank would do the same at 4.16a.

If thats correct (and I have no idea really if it is), at what power requirement would it make a difference to do say a 200ah 24v bank versus a 400ah 12v one? Are there any other benefits?

Think Phaselag is talking about voltage input to the controller, most bigger panels will put out 44+ volts, even if not at full watts. Not sure what that controller would do, might reduce voltage or not pass current at all. Believe I would go with a dedicated high voltage MPPT controller and a dedicated dc-dc only charger.

A lot involved with running a higher voltage system, including charging from alternator and converting higher voltage back to 12 volts. For smaller systems, only advantage I can see, is the smaller wiring.

Tomahawk · 12-14-2020, 07:04 PM

Increasing the battery bank voltage only seems valuable to me in two ways:
1) Reducing the current (Wire size and voltage drop) between the battery bank and an inverter.
2) Reducing the current between the battery bank and the solar charge controller.
The rest of the system is at 12V so the voltage needs to be stepped down.
The comment you made earlier is correct, Power = Voltage x Current, so if double the voltage, the current drops in half for the same power draw.
I think there are two advantages to running a higher voltage between the Solar Panels and the Solar Charge Controller (I use a 24 Volt panel):
1) You can run smaller gauge wires between the panels and Charge controller
2) The lower current results in less voltage drop and hence less power loss
3) The higher voltage panels are cheaper for some reason. Most 12V panels sell for about $1/watt but the the 24V panels can be had closer to $0.60/Watt.
Of course to take advantage of the higher voltage panels you need an MPPT Controller.

dmacd · 12-14-2020, 08:23 PM

Makes sense, guess I'll make that decision when I build a big battery bank, think I'll stay at 12V for now with 100AH lifepo4 for ease of use.

On another topic, for those of you with TT/RVs that have heated and enclosed tanks, what do you do about all the rest of the liquid plumbing? If it gets below freezing, wouldnt the fresh water and black tank flush inlets freeze? I'm headed down to Phoenix area in March when the TT arrives, but will probably have 1-2 days of sub freezing nights on the trip down. I'd like to be able to boondock those if possible, would it be a bad idea to winterize it, but fill the fresh tank full of water and anti freeze, and carry all the drinking/cooking water in portable jugs? How do you guys do it?

Bobby F · 12-14-2020, 09:40 PM

Quote:

Originally Posted by dmacd

. . . would it be a bad idea to winterize it, but fill the fresh tank full of water and anti freeze, and carry all the drinking/cooking water in portable jugs? How do you guys do it?

I'm leaving Minnesota for AZ tomorrow morning. It's 10 degrees here. My tanks are all empty - I'll get water when I get down south. I'm bringing several gallons of flushing water plus bottled water to drink. So, pretty much as you described it.

tuffr2 · 12-15-2020, 09:18 AM

Boondocking is a continue search for water, power and place to dump the tanks. I would semi boondock for 4 months on my property where I could get water from several sources, dump the tanks at a local state park, I did have electricy added to the wooded property which was a rip off. $35/mo just for the meter but one less thing to worry about. I had a generator and used it in the beginning so then I needed gasoline and a gas can.

Boondocking is not easy.