24V solar system - 12V DC question

[SolarPoweredRV]

Hey @SolarPoweredRV I was just going back over this thread to get a better understanding and I forgot that you said you added a couple small lithium batteries in addition to the orion for the dc side. does the orion charge those batteries while it's providing power to the hitch bolts where all the positive and negative wires are? I think I might just get another 12v battery to keep up front for that same situation plus just the comfort of having some kind of backup if anything goes wrong on the 24v side of the system.

I also figured out that my slideout motor is run by a 30A actuator and have not been able to find any info on surge amps but doesn't seem like itll be a problem for the 70A orion.

Yes, the two LiFePo4 batteries in the front compartment are wired just like the OEM Lead Acid batteries were. Additionally, the LiFePo4 batteries are not kept fully charged because the Orion has a constant output voltage of 13.1v and at 20ah they might not provide any meaningful "backup" power, beyond keeping the lights on. However, I can report that the hydraulic pump never seems to be working too hard or "sag" when under load, something I could not say was the case when the Lead Acid batteries were in place.

[jbartee7]

Yes, the two LiFePo4 batteries in the front compartment are wired just like the OEM Lead Acid batteries were. Additionally, the LiFePo4 batteries are not kept fully charged because the Orion has a constant output voltage of 13.1v and at 20ah they might not provide any meaningful "backup" power, beyond keeping the lights on. However, I can report that the hydraulic pump never seems to be working too hard or "sag" when under load, something I could not say was the case when the Lead Acid batteries were in place.

Hm ok well how do you charge them whenever they are completely discharged? or do you mean that the orion only trickle charges them a little and keeps them at enough charge for those surge amps you mentioned?

[SolarPoweredRV]

Hm ok well how do you charge them whenever they are completely discharged? or do you mean that the orion only trickle charges them a little and keeps them at enough charge for those surge amps you mentioned?

The Orion keeps them at a 13.2v constant state of charge. If they get drained during the hi amp draw event the Orion will get them up to 13.2v rather quickly.

The Orion acts just like the OEM Converter does with the original Lead Acid battery... A heavy load drains the battery (some) and eventually the Converter brings the LA battery up to the fully charged state.

I might add that I really like the Orion powering all my 12v devices inside the coach because it produces a constant 13.2v DC voltage to everything versus the variability you get with a standard OEM Converter/Lead Acid battery combination where the voltage drops down as low as 11v and the Converter can charge the battery as high as 14.4v. I believe that the constant voltage will help all my 12v devices live longer.

[jbartee7]

The Orion keeps them at a 13.2v constant state of charge. If they get drained during the hi amp draw event the Orion will get them up to 13.2v rather quickly.

The Orion acts just like the OEM Converter does with the original Lead Acid battery... A heavy load drains the battery (some) and eventually the Converter brings the LA battery up to the fully charged state.

I might add that I really like the Orion powering all my 12v devices inside the coach because it produces a constant 13.2v DC voltage to everything versus the variability you get with a standard OEM Converter/Lead Acid battery combination where the voltage drops down as low as 11v and the Converter can charge the battery as high as 14.4v. I believe that the constant voltage will help all my 12v devices live longer.

That is all great to hear! One more question, did you have to do any rewiring for the existing DC system? Just wanna make sure I don't fry any wires but I figure since I'm not changing any voltage or amp draw that all the legacy wiring would still be properly sized correct?

[SolarPoweredRV]

That is all great to hear! One more question, did you have to do any rewiring for the existing DC system? Just wanna make sure I don't fry any wires but I figure since I'm not changing any voltage or amp draw that all the legacy wiring would still be properly sized correct?

No, my OEM Converter had 6 AWG wires which can easily handle 70 amps from the Orion.

I did modify the wiring in the front hold however, because the two 10ah LiFePO4 batteries were so much smaller, and lighter, I was able to hang them high up on the front wall where they are out of the way. I might have replaced the existing 6 AWG up front with a smaller gauge wire to the LiFePo4 batteries, I don't recall.

[Ranger Rick]

Do you have a 12v to 24v DC to DC charger from your truck 12-volt battery to your RV 24-volt battery bank? If yes, what model and wiring? Thank you 😊

[Ranger Rick]

Sprice, Do you have a 12v to 24v DC-DC charger in your setup? If yes, what model? Plus any tips on installing it? Thank you, Rick

[SolarPoweredRV]

Do you have a 12v to 24v DC to DC charger from your truck 12-volt battery to your RV 24-volt battery bank? If yes, what model and wiring? Thank you ��

Sprice, Do you have a 12v to 24v DC-DC charger in your setup? If yes, what model? Plus any tips on installing it? Thank you, Rick

Initially, I did not have charging from my truck to the RV because of the 24v battery bank and I simply felt that I could rely on the 1200 Watts of Solar to keep my batteries charged. Now, some 3 years later, I am revisiting that decision. On a recent trip, we were goiing to be boondocking overnight and I used a little too much energy running the air conditioner during our lunch stop. Unfortunately, that afternoon was cloudy and the Solar did not recharge my battery bank as much as I had hoped they would (we were fine overnight, just a little bit too close to the edge for comfort). Consequently, I am now installing a 12v to 24v Victron DC to DC Converter.

The first thing I had to consider is: what size DC to DC Converter would add an appreciable amount of energy to a large battery bank like mine (~ 1,000 ah)? I also had to consider how many amps the DC to DC Converter would draw from the truck, since I will be installing a 12v to 24v (up-voltage) Converter, the amp draw on the truck will be twice the amp rating of the Converter. I first considered a 15 amp Converter, but then I thought about the actual contribution to the battery bank in terms of "how much energy would I get over time on a 12v basis"? 15 amps would yield 30 amps per hour, figuring on a 4 to 5 hour drive that is 120 to 150 ah (@ 12v) added to my battery bank, not bad, but also not a big contribution to a large battery bank like mine. Consequently, I decided on a 20 amp Converter which would add ~ 160 to 200 ah of charge, not an insignificant amount of energy. At the same time, the draw on my truck's electrical system is not too great (~ 40 amps, with a 60 amp surge possibility).

Installing the Converter on the truck has been quite interesting because Ford did not leave very much space inside the engine compartment to install even a fuse. I installed a 60 amp breaker (Converter is rated at 20 amp with a 30 amp surge capability) I am using 100 feet of 6 awg cable to get the power all the way back to the camper (50 feet of red and 50 feet of black). I am also installing a two pole "lift gate" type connector and socket to transfer the power from the truck to the camper (originally I was going to use Anderson connectors, but I couldn't figure out how to waterproof the connection. Note: here is a link to the type of connector I am talking about...

https://www.amazon.com/POLLAK-2-Pole...a-568823777202

I chose to I stall the Converter behind the rear passenger seat because the space behind the driver's side was consumed by sound system components.

The Converter can be controlled from the driver's seat through one of the upfitter switches installed on the truck (definitely worth getting the upfitter switch option on your truck).