I went to the Danger Zone

[thirdsandbar]

I went to the Danger Zone.. I have mounted 6 SunPower SPR X21-335 PVs on 2007Coachman Mirada.
I am ordering a pair of BigBattery 24V 170ah LiFePO4 Power Blocks, for 48V config. Yes.. going BIG.
This Class A RV is a 50a config. There are no 240 appliances... the dist panel divides the loads on for
each of the 120s. I will not be adding or changing any electrical wiring. I will install the inverter, chg ctlr in
RV's external power bay where an existing 50a receptacle from an onboard 5500w Onan and the RV's
50a service cable is for plugging into shore power (or the Onan receptacle). No transfer management exists
or is wanted. I will simply plug the RV's 50a service cable into shore pedastal, Onan receptacle or new inverter.
The main driver for this approach is easy install, easy removal, easy use, all without wiring work to RV.
Notably, the 48v batt array will sit on the RV floor above the external power bay for short, easy connection.

I am getting vertigo from comparing wired power centers, reputable 4400w and above inverter/chargers,
ample charge controllers for connecting PVs 2s3p. Taking a timeout and tossing out for responses, comments.

Thank you in advance for gawks, coughs, laughs, but especially useful feedback or ideas. Rick

​

 

[HRTKD]

My system is 30 amp, so I can't offer any advice. But I do see some merit to your approach. It keeps it simple.

Should you connect to a shore power pedestal, how will that charge the battery bank? Or are you expecting to do all charging from the solar panels?

 

[thirdsandbar]

My system is 30 amp, so I can't offer any advice. But I do see some merit to your approach. It keeps it simple.

Should you connect to a shore power pedestal, how will that charge the battery bank? Or are you expecting to do all charging from the solar panels?

Thank you for your comment post... We will have occasion to boondock and access shore power. I will count on charging from PVs except
during shaded stints, extended poor weather without sufficient sun or a time crunch...then I will charge from the inverter/charger or stand-alone charger. I have begun a discussion with an experienced solar designer/deployer, but am actively seeking input from anyone/everyone. Please let me know if you can provide me contact info of any DIY or professionals that have RV/off-grid/ 48v 4400w inverter or larger experience. I have 2010w of PVs suited to the 48v config I am implementing. Rick

 

[snoobler]

I'm pretty sure you said as much, but please clarify that in order to use your generator, you have to plug your 50A umbilical into a NEMA 14-50R receptacle in your power bay. Thus your RV has no transfer switch.

If that's the case, you're planning:

Solar panels -----> charge controller -----> 48V battery -----> inverter ----->NEMA 14-50R female receptacle into which you will plug in your RV 50A umbilical.

In order to get 120V on both legs of your RV panel, you will need to short the L1 and L2 on the NEMA 14-50R receptacle. Alternatively, you could use a NEMA TT-30R receptacle requiring the 30A to 50A adapter, which does this internally. It also gives a visual indication of the system's limitations.

Note that this configuration has a limitation. In the shore power configuration, there is little current flow in the Neutral except for imbalance between the two legs. In the proposed configuration, the Neutral handles the current on BOTH legs, so you will be limited to 50A on the neutral or 6000W total. That's a tall order for your system, so it's likely not an issue.

I recommend you consider a Magnasine MS4448PAE. It can operate in both 120V or 240V split phase.

The down side to your proposal is that you can't charge your batteries while on shore power unless you purchase an AC powered 48V charger. You could charge them off the generator by fashioning a plug into the generator. Just make sure your generator is connected suitably for its output, 120 or 240VAC.

 

[thirdsandbar]

I'm pretty sure you said as much, but please clarify that in order to use your generator, you have to plug your 50A umbilical into a NEMA 14-50R receptacle in your power bay. Thus your RV has no transfer switch.

If that's the case, you're planning:

Solar panels -----> charge controller -----> 48V battery -----> inverter ----->NEMA 14-50R female receptacle into which you will plug in your RV 50A umbilical.

In order to get 120V on both legs of your RV panel, you will need to short the L1 and L2 on the NEMA 14-50R receptacle. Alternatively, you could use a NEMA TT-30R receptacle requiring the 30A to 50A adapter, which does this internally. It also gives a visual indication of the system's limitations.

Note that this configuration has a limitation. In the shore power configuration, there is little current flow in the Neutral except for imbalance between the two legs. In the proposed configuration, the Neutral handles the current on BOTH legs, so you will be limited to 50A on the neutral or 6000W total. That's a tall order for your system, so it's likely not an issue.

I recommend you consider a Magnasine MS4448PAE. It can operate in both 120V or 240V split phase.

The down side to your proposal is that you can't charge your batteries while on shore power unless you purchase an AC powered 48V charger. You could charge them off the generator by fashioning a plug into the generator. Just make sure your generator is connected suitably for its output, 120 or 240VAC.

Snoobler... your comment post is tremendously appreciated. I've given the ms4448pae strongest consideration of any so far. I need an mmp. Although I accumulated experience with 48v on Telecom deployments, I am treading carefully. I have been guided by the magnum site and docs but am insecure in my interpretations and level of understanding. There are prewired power center offered by distributors. Most expensive, most attractive way for me. I'm concerned that the external RV bay best suited would require I lay the 4448, mmp and pt-100 horizontally... I have some concern for resulting heat dissipation as opposed to a traditional vertical mount. Next I need to consider if I need to purchase additional breakers. I also read the product note stating that 200ah or bigger batt array is best...I'm equipping 48v 170ah. I don't know if that's an issue. Has anyone out there gone big in a Class A with an ms4448pae? Snoobler... I will stay vigilant for your further comments. Thank you to all of you and the collective, shared knowledge. Rick

 

[BobH]

The ECPC Hybrid Inverters linked below are supposedly Deye/SunSynk Hybrid Inverters & offer just about all the options you're describing. I don't think anyone on the forum has evaluated these or had them in their hands yet, but they have a solid reputation in other countries. The 5K option has grid, solar (2 mppt's), & generator inputs. If your battery is already 48V & your elect. panel already accepts 240V, then it seems to cover all of your requirements...

https://www.electriccarpartscompany.com/5kw-ul-approved-dc-ac-power-hybrid-inverter

Link to the manual - https://www.electriccarpartscompany.com/assets/images/HYBRID INVERTER USER MANUAL.pdf

 

[snoobler]

Snoobler... your comment post is tremendously appreciated. I've given the ms4448pae strongest consideration of any so far. I need an mmp. Although I accumulated experience with 48v on Telecom deployments, I am treading carefully. I have been guided by the magnum site and docs but am insecure in my interpretations and level of understanding. There are prewired power center offered by distributors. Most expensive, most attractive way for me. I'm concerned that the external RV bay best suited would require I lay the 4448, mmp and pt-100 horizontally... I have some concern for resulting heat dissipation as opposed to a traditional vertical mount. Next I need to consider if I need to purchase additional breakers. I also read the product note stating that 200ah or bigger batt array is best...I'm equipping 48v 170ah. I don't know if that's an issue. Has anyone out there gone big in a Class A with an ms4448pae? Snoobler... I will stay vigilant for your further comments. Thank you to all of you and the collective, shared knowledge. Rick

Horizontal vs. vertical really depends on the manufacturer's design and recommendations. I haven't consulted the manual.

200Ah is likely based on FLA/AGM batteries to ensure they can deliver 4000W of current and maintain a usable voltage as well as accept the charge current from the inverter/charger. Your 170Ah LFP battery is fine.

I didn't "go big", but I have off-grid "shore power" via my 48V bank and Victron 5k/48V in a shipping container with 3kW of solar. I have a 50A power pedestal outside the container with the L1 and L2 jumpered since Victron is 120VAC only. For about a year now, it's run a Newmar 5th wheel and our 34' Newmar Mountainair. Power conservation is necessary when using both, but it's been very managable.

The solution is very simple and has no significant implications as it's stationary. You being mobile creates the issue with shore power variations.

 

[HRTKD]

I have a 50A power pedestal outside the container with the L1 and L2 jumpered since Victron is 120VAC only.

The Victron's Quattro line supports an input voltage range of 187-265 VAC. If you had that unit, how would it fit in with your 50 amp pedestal if the pedestal was wired like you would find at a campground?

 

[snoobler]

That's for their 230VAC 50Hz models.

They have up to Quattro 5kW in 120VAC 60Hz in and out only. That's what I have.

https://www.victronenergy.com/upload/documents/Datasheet-Quattro-3-10kVA-120V-EN.pdf

90-140VAC input range.

 

[HRTKD]

I guess what I'm asking is, if a trailer that is currently setup for 50 amp service, is the 50 amp 240vac version of the Quattro a better fit than the 120vac version?

 

[snoobler]

I guess what I'm asking is, if a trailer that is currently setup for 50 amp service, is the 50 amp 240vac version of the Quattro a better fit than the 120vac version?

There isn't one. There is a 230VAC 50Hz version that's single phase. There is no neutral. Victron does not offer a suitable 240VAC product for North America. An autotransformer can be added, but that adds more cost to an already costly unit.

The proposed magnasine unit is cheaper and offers the option of 120VAC operation or 240VAC split phase operation.

 

[HRTKD]

Thanks, I think that answers my question. Should I move up to a fifth wheel RV with 50 amp service, I need to know what it's going to take to retrofit it for a full solar/LiFePO4 upgrade. Long term planning.

 

[cinergi]

I went to the Danger Zone.. I have mounted 6 SunPower SPR X21-335 PVs on 2007Coachman Mirada.
I am ordering a pair of BigBattery 24V 170ah LiFePO4 Power Blocks, for 48V config. Yes.. going BIG.
This Class A RV is a 50a config. There are no 240 appliances... the dist panel divides the loads on for
each of the 120s. I will not be adding or changing any electrical wiring. I will install the inverter, chg ctlr in
RV's external power bay where an existing 50a receptacle from an onboard 5500w Onan and the RV's
50a service cable is for plugging into shore power (or the Onan receptacle). No transfer management exists
or is wanted. I will simply plug the RV's 50a service cable into shore pedastal, Onan receptacle or new inverter.
The main driver for this approach is easy install, easy removal, easy use, all without wiring work to RV.
Notably, the 48v batt array will sit on the RV floor above the external power bay for short, easy connection.

I am getting vertigo from comparing wired power centers, reputable 4400w and above inverter/chargers,
ample charge controllers for connecting PVs 2s3p. Taking a timeout and tossing out for responses, comments.

Thank you in advance for gawks, coughs, laughs, but especially useful feedback or ideas. Rick

​

You might be interested in my build: https://diysolarforum.com/threads/cinergis-28-kwh-4-kw-solar-10-kw-inverter-rv-build.13786/