Taking our dry camping electrical up a notch

[zayd]

After a 2-year break, we are back into an Airstream. I've recently picked up a 2016 25' FBT. It was well cared-for, and the previous owner had already made some good electrical upgrades:

- PD4655 Converter/Charger
- 470W of solar (AM Solar)
- Bogart TM-2030 RV Battery monitor (AM Solar)
- Bogart SC-2030 4-stage solar charge controller (AM Solar)
- (2) 220ah Lifeline AGMs (about 6 years old)

We mostly dry camp for about a week at a time but don't have excessive electrical needs. With this current setup and with our typical tree-covered camping, we can usually go 3, maybe 4 days with minimal furnace usage, the fridge on propane, and occasional inverter usage. This is while staying above 50% SOC.

I had originally planned on an extensive Victron re-do. But while I envy the Victron/Li setups that I've seen here, it is simply more than we need and will be overkill. The factory 1000W inverter and dedicated outlets will suffice us, and I only need basic on-site power monitoring.

Based on hours of research on this forum and others, this is where I've landed. I'd like validation that this is a sensible approach:

1. Battery: Replace the AGMs with one 470Ah Epoch LiFePO4 battery, mounted inside the front compartment.

2. Converter/Charger: PD4655 stays but with a jumper setting to accommodate the lithium battery

3. Battery Monitor: Victron SmartShunt. However, the Epoch has a BMS with built-in Bluetooth, so perhaps this is unnecessary? The BMS should cover basic monitoring, including incoming/outgoing data. I could leave the Bogart as a secondary monitor.

4. Solar: Victron MPPT Solar Charge Controller to replace the current PWM one.

5. Tow Charging: Victron 12/12-18 DC-DC charger to keep the battery topped off without running a dedicated battery line from the tow vehicle. The alternative here is that maybe the new MPPT controller will optimize solar charging enough that I don't need the additional TV charging. In that case, I could pull the charging 7-way pin to isolate the trailer.

Any feedback on this setup? Adjustments to optimize the installation without going nuts with the investment? I appreciate the guidance.

[BikeCamper]

Seems like a pretty solid upgrade plan.

No, you don’t need the shunt. The BMS will give you the same info. (As long as whoever is using the trailer has the app.)

Would you consider going with two of the Epoch 330ah batteries? This would give you a serious bump in reserve capacity.

[zayd]

Thanks for the validation.

I did consider a couple of the 300Ah batteries, but the 460Ah offers a significantly better Ah/$ ratio. I also planned to bring the battery(ies) inside anyway to save some tongue weight and keep the electronics inside, so the conventional form factor of the 300Ah batteries didn't appeal to me from that perspective either. Adding a second 460Ah would also be easy with everything inside.

But if you plan to keep the batteries in the outside box, you are absolutely right -- it's hard to beat a pair of their 300s.

[1StreamDream]

I have the victron 12/12/18 with factory tow vehicle wiring (no separate wire) and I get good use out of that charging capability, it is a wise addition to give you some additional charging option and tow vehicle electrical isolation. Only other item I would suggest is you might consider investing in some portable solar panels, you mention tree covered camping, we like to do similar, and find that with a portable panel (or two) we can usually find a sun spot that gets of several good hrs of charging a day. The Lithium upgrade alone should almost double your dry camping runtime, and a benefit not often mentioned is that Lithium will recharge much quicker than lead acid (I think Lithiums have lower internal resistance, thus they get replenished more efficiently). I have a pair of 220w portable panels from Renogy, nice and light, fold up small, but you will also need a dedicated controller for the portable panels, separate from the rooftop panels, in order to maximize solar panel charging efficiency.

[kb0zke]

FWIW, I have a pair of 24V LiFePO4 batteries, so the truck to trailer charging line has been disconnected. The 1095W of solar panels on the roof keep the trailer batteries charged while driving or while parked.

[StogieMan]

Originally Posted by BikeCamper

No, you don’t need the shunt. The BMS will give you the same info.

No, not necessarily.

Originally Posted by zayd

Any feedback on this setup? Adjustments to optimize the installation without going nuts with the investment? I appreciate the guidance.

First, if you’re not going to install a Victron system where the Victron Comms would be a benefit - save yourself some money and go with the 460’s without Victron Comms. I just installed two of these with Victron Comms and have first hand knowledge of their workings. The Epoch batteries and most of the internal state of charge meters on most batteries are not accurate so you should still add a separate Victron Shunt to your system. I think that they are right around $100 and worth it if you want or need accurate info. I have and find that the internal Epoch BMS shunt drifts from the Victron one. This is not new to Epoch and many batteries do the same. Trust me as I’ve spent a ton of time researching this. The Epoch shunt actually can’t count any amps under 1.0 amps where the Victron shunt can do so up to 0.1 A’s. This is where the drift comes in and you can only tell if you have both shunts and are able to view them. Without the additional shunt, you would have no idea of what’s going on and left in the dark. With two in parallel like I have them - the drift widens.

Lastly, if you go with the Epoch 460 AH, you should set your absorption rate to 13.8 or 13.9 and your float to 13.4 or 13.5. Again, I’ve done the research if you want to save yourself some time if not - you’re free to go down the rabbit hole that I went down. I have finally been able to dial them in - the Victron BMV 712 Shunt and the Epoch shunt to work in close to harmony. I’ve been slowly drawing them down and back up to a full charge for a few days now along with different absorption and float rates. 13.8 for a Lithium battery is actually not bad and so is the 13.4 float rate. There is a YouTuber that has had Lithium batteries for 15 years now with an absorption rate of 13.8 and he has actually convinced me to that side of the fence. Yes, there are nay sayers and in between so please go with what you feel comfortable with. I’m good with 13.8 Absorption and 13.4 Float rate.

[zayd]

Originally Posted by 1StreamDream

I have the victron 12/12/18 with factory tow vehicle wiring (no separate wire) and I get good use out of that charging capability, it is a wise addition to give you some additional charging option and tow vehicle electrical isolation. Only other item I would suggest is you might consider investing in some portable solar panels, you mention tree covered camping, we like to do similar, and find that with a portable panel (or two) we can usually find a sun spot that gets of several good hrs of charging a day.

I am beginning to lean this way as well. Based on previous experience, there will be times when I might rely on a few hours of towing to boost the charge, and having that capability is sensible. Thanks for the nudge on the portable solar -- something to think about.

Originally Posted by StogieMan

First, if you’re not going to install a Victron system where the Victron Comms would be a benefit - save yourself some money and go with the 460’s without Victron Comms.

Totally agree. Since I don't plan on the whole Victron ecosystem, I am going with the basic 460Ah. I'll take your advice on the SmartShunt -- I didn't know the battery BMS was that imprecise. With this investment, it wouldn't make sense to leave myself in the dark on SOC.

Originally Posted by StogieMan

Lastly, if you go with the Epoch 460 AH, you should set your absorption rate to 13.8 or 13.9 and your float to 13.4 or 13.5.

I am glad to learn from your journey down that rabbit hole! In. general, I still have a lot to learn about this. Our previous Airstream had no solar and the original single-stage converter/charger. Are you referring here to the settings on the solar charge controller? Or if you're referring to the PD4655, the manual describes the LiIon setting as a 14.5-14.6V charge, and the lead acid as a 13.2-14.4V charge.

[StogieMan]

Originally Posted by zayd

Are you referring here to the settings on the solar charge controller? Or if you're referring to the PD4655, the manual describes the LiIon setting as a 14.5-14.6V charge, and the lead acid as a 13.2-14.4V charge.

Actually, I have a van and don't have a trailer with a converter if that's what your referring to with the PD4655. However, I had to adjust the settings on our Victron Multiplus 3K Inverter, Victron BMV 712 Shunt, MPPT 100/50 Roof Solar Array, MPPT 100/30 Ground Solar Array and both of our 50A Victron Orions XS alternator chargers.

So yes, you'll need to update some settings on some off your equipment or all that have anything to do with charging your batteries.

[BikeCamper]

Re the shunt, I was going by what Epoch told me when I was inquiring about their batteries and the BMS (specifically the 330ah version.)

Based on what they described, I would not bother with the shunt. I will concede that a dedicated shunt may be more accurate. But I don’t require that level of precision amp tracking. I find too much data/detail can end up being a distraction.

I am just looking for a reasonable approximation. I’m comfortable that the BMS would get me close enough.

[G8trwood]

If getting other Victron equipment, the smart shunt makes sense as they all talk to each other and you get more accurate measurements. The solar controller gets data from the shunt and can adjust voltage due to wire voltage drop.

There are a lot of comments on the 460 on panbo and marine cruiser forums . I think the 13.8 and 13.4-13.5 is also their recommendation. The progressive chargers run pretty hot, I’m not sure if they can turn them down or not.

[SuperTrouper]

I've had solar for 11 years, upgraded to an Epoch 460AH this year (went from (2) Lifeline AGM to Chins 300AH to Epoch 460. I reused the Chins with a inverter for my home office backup power. I agree with Stogieman. A smartshunt is the only way that you can accurately measure power in and out of the battery over time. I'm going to recheck my absorption and float voltages on my BlueSky controller based on his findings. BTW: I did contact Epoch to check if keeping the battery charged was detrimental to the life of the battery as I leave the systems on in storage. Epoch's support answer "You can keep the battery fully charged, it doesn't have a negative effect with lithium." One thing to add for your proposed upgrades, I purchased a Victron 12-12 18A charger for TV charging using existing TV wiring and found that it drew too much current and blew the TV charging circuit fuse (20A). I swapped it for a Orion XS "smart" charger which allows you to set limits on the current draw. I dialed it back to 10 amps as my 7 way plug was heating up at 18Amps. I plan to replace both sides of the 7 way to get a better connection. The real way to do it would be to run fused #4 wire from the battery of the TV back to an anderson connector for the TV charging but with 510 watts of solar and the Epoch 460AH battery capacity, it isn't worth the trouble for me to increase the TV charging capacity. I also have a Yamaha generator with a propane kit for worst case dry boondocking. One more thing I would add is this little $30 device across the battery terminals to measure voltage over time. https://www.amazon.com/gp/product/B01MT4583U/?th=1 I find it useful to look at the history of charging. Attached is a screen shot of a cloudy week at the beach that caused me to upgrade from 300AH to 460AH. If I was building a system from the start today I'd go all Victron but when i installed solar Victron hadn't come out with all the fancy systems yet.

[JeffKim]

I'm usually enthusiastically all-in with Victron equipment and upgrades. With that I agree with others that a Victron shunt is best. However, with the battery you're installing you'll get 4x what you have with your AGMs so effectively you won't be without power for more than a couple weeks with your current usage. Do you plan on being unplugged for longer than this? Any other additions I think you're right are overkill including external panels which will require another solar controller.

With your modifications I'd add a battery cutoff switch and a solar panel breaker.

Other than that, as suggested above check on your TV DC charging capabilities. the Victron Orion XS is a marvelous piece of technology. My TV is limited to 15A so the 18A charger didn't work for me (it can draw up to 24A or so). The XS lets me set the input current exactly and works flawlessly.

If you do have a change of plans or more money in the pocketbook - as noted above, if you go with all-Victron Smart charging it will coordinate the charging via VE.Smart Networking. I have a Victron Phoenix 50A charger which is pricier than the PD but I can monitor charging and it adjusts its voltage to account for loss according to what the shunt is telling it. Same for the solar controllers. I have an extra Victron MPPT 100|30 dedicated to external panels since they often have a different solar exposure.

Also don't discount the entertainment value of monitoring all your devices on your phone with the Victron app. I can spend hours out in glorious nature staring at my phone, checking my battery level and moving the solar panels.

[BikeCamper]

Originally Posted by SuperTrouper

… A smartshunt is the only way that you can accurately measure power in and out of the battery over time. ….

I’m curious why you feel it’s necessary to track this?

I have and have had multiple battery banks (home, boats, travel trailer, etc) over decades and have never needed this data. The battery banks have always performed very well and given great service. And yet I’ve never felt I needed to keep track of the power in and out over time.

I’m not saying the info couldn’t be useful. I just have never felt like I needed it to get good service from batteries.

[foobar]

Originally Posted by zayd

After a 2-year break, we are back into an Airstream. I've recently picked up a 2016 25' FBT. It was well cared-for, and the previous owner had already made some good electrical upgrades:

- PD4655 Converter/Charger
- 470W of solar (AM Solar)
- Bogart TM-2030 RV Battery monitor (AM Solar)
- Bogart SC-2030 4-stage solar charge controller (AM Solar)
- (2) 220ah Lifeline AGMs (about 6 years old)

We mostly dry camp for about a week at a time but don't have excessive electrical needs. With this current setup and with our typical tree-covered camping, we can usually go 3, maybe 4 days with minimal furnace usage, the fridge on propane, and occasional inverter usage. This is while staying above 50% SOC.

I had originally planned on an extensive Victron re-do. But while I envy the Victron/Li setups that I've seen here, it is simply more than we need and will be overkill. The factory 1000W inverter and dedicated outlets will suffice us, and I only need basic on-site power monitoring.

Based on hours of research on this forum and others, this is where I've landed. I'd like validation that this is a sensible approach:

1. Battery: Replace the AGMs with one 470Ah Epoch LiFePO4 battery, mounted inside the front compartment.

2. Converter/Charger: PD4655 stays but with a jumper setting to accommodate the lithium battery

3. Battery Monitor: Victron SmartShunt. However, the Epoch has a BMS with built-in Bluetooth, so perhaps this is unnecessary? The BMS should cover basic monitoring, including incoming/outgoing data. I could leave the Bogart as a secondary monitor.

4. Solar: Victron MPPT Solar Charge Controller to replace the current PWM one.

5. Tow Charging: Victron 12/12-18 DC-DC charger to keep the battery topped off without running a dedicated battery line from the tow vehicle. The alternative here is that maybe the new MPPT controller will optimize solar charging enough that I don't need the additional TV charging. In that case, I could pull the charging 7-way pin to isolate the trailer.

Any feedback on this setup? Adjustments to optimize the installation without going nuts with the investment? I appreciate the guidance.

Real world feedback.

The victron 12-12-18 dc-dc charger is pretty much useless whenever the solar charger is charging the batteries. The reason is pretty simple. The 12-12-18A charger is not able to be networked with any other battery monitoring or charging equipment and can only determine which charge state it is in via monitoring the voltage at it's output terminal. When the solar charger pumps out 14.2v to charge the batteries in bulk mode, the victron 12-12-18A charger thinks the batteries are nearly fully charged and enters absorption mode (or even float mode) and stops producing significant charging current. I have been using this dc-dc charger for two years and last week, I yanked it out and replaced it.

As illustrated in the last paragraph above, it's important that all of your equipment can communicate with each other and coordinate their charging states.

I recommend the following if your budget allows.

Victron smart shunt
Victron smart bluetooth mppt solar controller
Victron Orion XS bluetooth 12v-12v, 50A dc-dc charger

All of the above equipment can be networked together over bluetooth. The Victron smart shunt can communicate battery state and the voltage of the battery bank to the solar controller and the Orion XS dc-dc. The solar controller and the Orion XS will coordinate their charging states.

The Orion XS has programmable control over input and output current limits (unlike the 12v-12v, 18A Orion Tr) so you can easily limit the input current level to whatever your tow vehicle + 7pin wiring can handle).

You can greatly enhance the utility of the above system recommendation by adding a victron Cerbo GX and Touch 50 or Touch 70 display unit. This would provide a touch screen graphical monitor and control capability and also supports bluetooth, wifi, and ethernet based networking for remote control and monitoring. It also can be networked with all of the victron batteries and equipment for smart system control and monitoring.

For example, my cerbo GX monitors and displays my propane tank levels, my black, grey, and fresh water tank levels. The cerbo also monitors the wireless temp sensors I have installed in the fridge, freezer, and bedroom and lounge areas and triggers alarms on my phone if the fridge or freezer temps rise above a critical threshold (so I know if my fridge or freezer door has come open on the road, or the fridge has failed, etc). It also triggers a high temp alarm on my phone if the lounge/bedroom sensors are out of spec (I plan to use this capability to ensure than any dogs I leave in the trailer are safe if we lose power and a/c while we are away from the trailer).

It's really cool to be able to stand out by the black tank valve and monitor the black tank level when I am adding water to flush the tank. I don't have to have a second person inside watching the tank level display, or I don't have to make multiple trips inside to check on the level.

The cerbo can be networked to a pepwave cellular modem via ethernet or wifi and then you can monitor and control everything while you are away from the trailer. My pepwave setup also has a GPS antenna and receiver, so I can monitor the trailer position remotely in case of theft.

It's really best if you get all of your equipment from one vendor (I highly recommend Victron equipment) and then network everything together to maximize the overall capability. While you can piecemeal together a heterogenous system, it's not going to perform optimally.

[SuperTrouper]

Originally Posted by BikeCamper

I’m curious why you feel it’s necessary to track this?

I have and have had multiple battery banks (home, boats, travel trailer, etc) over decades and have never needed this data. The battery banks have always performed very well and given great service. And yet I’ve never felt I needed to keep track of the power in and out over time.

I’m not saying the info couldn’t be useful. I just have never felt like I needed it to get good service from batteries.

Hi Bike Camper. I like to know how many amp hours a day I use or are fed back into the battery bank by the solar so that I can calculate when/if a generator will be required during a long boondocking stay. This was more important when I had AGM batteries but I still rely on the shunt to tell the truth so I can plan ahead. My shunt is tied to my BlueSky solar controller.

[richard5933]

Originally Posted by BikeCamper

I’m curious why you feel it’s necessary to track this?

I have and have had multiple battery banks (home, boats, travel trailer, etc) over decades and have never needed this data. The battery banks have always performed very well and given great service. And yet I’ve never felt I needed to keep track of the power in and out over time.

I’m not saying the info couldn’t be useful. I just have never felt like I needed it to get good service from batteries.

With a lead acid battery bank you can get a pretty useful looks at the state of charge by just checking the voltage. Not totally accurate but close enough for most needs.

With lithium batteries, the voltage will hold nearly constant until the batteries are at the end of their discharge cycle. Looking at the voltage won't really tell you if you're at 80%, 50%, or 40%. This kind of information is useful in daily use, especially if you're in a situation where the solar isn't great and you're trying to stretch out your battery capacity throughout the day.

A shunt-based monitor is really the only accurate way to know the state of charge of a lithium battery bank. You're correct that knowing the fine minute-by-minute data isn't generally useful, but it is really helpful to know how much of your battery capacity is used overnight, when using the microwave, etc. so you can better judge what should/should not be used depending on the charging conditions.

[BikeCamper]

I get that a li-ion battery can’t be monitored by voltage alone. But the BMS system built into many of the latest li-ion batteries gives a very good approximation of the state of charge. For my purposes, all I need to know is that the batteries are (1) fully or nearly fully charged, and (2) getting low and needing a charge. Have never needed more granularity than that.

I guess it’s a difference in approach. Extra specific data about electrons in/out wouldn’t improve or enhance my camping experience. If anything it would just become yet another distraction. I prefer just to charge the batteries when they’re getting low, and not give it much thought otherwise.

[richard5933]

Originally Posted by BikeCamper

I get that a li-ion battery can’t be monitored by voltage alone. But the BMS system built into many of the latest li-ion batteries gives a very good approximation of the state of charge. For my purposes, all I need to know is that the batteries are (1) fully or nearly fully charged, and (2) getting low and needing a charge. Have never needed more granularity than that.

I guess it’s a difference in approach. Extra specific data about electrons in/out wouldn’t improve or enhance my camping experience. If anything it would just become yet another distraction. I prefer just to charge the batteries when they’re getting low, and not give it much thought otherwise.

If your BMS already gives you the same data as a shunt monitor, then I'd agree that it would be redundant. Not all lithium batteries include a BMS that provides state of charge information though.

[SuperTrouper]

Originally Posted by SuperTrouper

Hi Bike Camper. I like to know how many amp hours a day I use or are fed back into the battery bank by the solar so that I can calculate when/if a generator will be required during a long boondocking stay. This was more important when I had AGM batteries but I still rely on the shunt to tell the truth so I can plan ahead. My shunt is tied to my BlueSky solar controller.

I'm taking a step back on this. When I installed my solar, Lifeline 6V AGM was the way to go and I needed a shunt to accurately count amp hours. As you and others have pointed out, and I confirmed yesterday when checking on the trailer in storage, I can now get the same information from my Epoch 460AH Bluetooth BMS monitor so the shunt is, as you pointed out, redundant.

[KK4YZ]

Originally Posted by zayd

After a 2-year break, we are back into an Airstream. I've recently picked up a 2016 25' FBT. It was well cared-for, and the previous owner had already made some good electrical upgrades:

- PD4655 Converter/Charger
- 470W of solar (AM Solar)
- Bogart TM-2030 RV Battery monitor (AM Solar)
- Bogart SC-2030 4-stage solar charge controller (AM Solar)
- (2) 220ah Lifeline AGMs (about 6 years old)

We mostly dry camp for about a week at a time but don't have excessive electrical needs. With this current setup and with our typical tree-covered camping, we can usually go 3, maybe 4 days with minimal furnace usage, the fridge on propane, and occasional inverter usage. This is while staying above 50% SOC.

I had originally planned on an extensive Victron re-do. But while I envy the Victron/Li setups that I've seen here, it is simply more than we need and will be overkill. The factory 1000W inverter and dedicated outlets will suffice us, and I only need basic on-site power monitoring.

Based on hours of research on this forum and others, this is where I've landed. I'd like validation that this is a sensible approach:

1. Battery: Replace the AGMs with one 470Ah Epoch LiFePO4 battery, mounted inside the front compartment.

2. Converter/Charger: PD4655 stays but with a jumper setting to accommodate the lithium battery

3. Battery Monitor: Victron SmartShunt. However, the Epoch has a BMS with built-in Bluetooth, so perhaps this is unnecessary? The BMS should cover basic monitoring, including incoming/outgoing data. I could leave the Bogart as a secondary monitor.

4. Solar: Victron MPPT Solar Charge Controller to replace the current PWM one.

5. Tow Charging: Victron 12/12-18 DC-DC charger to keep the battery topped off without running a dedicated battery line from the tow vehicle. The alternative here is that maybe the new MPPT controller will optimize solar charging enough that I don't need the additional TV charging. In that case, I could pull the charging 7-way pin to isolate the trailer.

Any feedback on this setup? Adjustments to optimize the installation without going nuts with the investment? I appreciate the guidance.

Looks like a great setup to me as long as you’re fine with the standard inverter.

We enjoy the multiplus 3000w inverter charger because it allows us to make a cup of coffee with the Kurig or nuke something in the microwave while still on battery power, but that’s just us.