Victron System with EG4 rack Mount

[jameshowison]

Hah, Not me, I’ve got Jakiper batteries hooked up to Victron

 

[dab1294]

Anybody else cringe when they hear EG4 and Victron used in the same sentence?

Is there a reason for this?

 

[dab1294]

A 24v system would look basically the same, with three main differences:

At this point, Maybe a 48v system would make even more sense. Because the 48v Eg4 has a 100ah max discharge, which would solve my problem there too.

 

[John Frum]

At this point, Maybe a 48v system would make even more sense. Because the 48v Eg4 has a 100ah max discharge, which would solve my problem there too.

Its hard to find inverter/chargers of the capacity you need in 48 volts.

 

[John Frum]

At this point, Maybe a 48v system would make even more sense. Because the 48v Eg4 has a 100ah max discharge, which would solve my problem there too.

You didn't answer my question about your RV being a 50 amp@240VAC shore power.

 

[dab1294]

You didn't answer my question about your RV being a 50 amp@240VAC shore power.

Ah sorry! No, it is 30a

 

[dab1294]

Its hard to find inverter/chargers of the capacity you need in 48 volts.

I am tempted to go back to my original plan of using the LV6548 and an Eg4. That seemed so much simpler.

 

[John Frum]

I am tempted to go back to my original plan of using the LV6548 and an Eg4. That seemed so much simpler.

When you picked the multiplus 2 at 12 volts I assumed you would be using this one.

MultiPlus-II 2x 120V - Victron Energy

The MultiPlus-II 2 x120V is the perfect one-box mobile solution for standard North American 50A 120/240VAC split-phase applications.

www.victronenergy.com

It has a very special transfer switch(unique feature) that works with 50amp shore power.

If you just need to work with 30 amps@120VAC then you have more options.

The LV6548 is not ul-458 certified and isn't really made for the mobile usage model.
I've never got a straight answer from the company on how their automatic transfer switch handles the neutral-ground bond.
ul-458 certified inverter/chargers handle this correctly.

The LV6548 can draw up to ~160 amps so you would need 2x of the eg4 batteries supply it.

48->12VDC converters are also hard to source in the capacity that you would require.
Its my policy to replace the ac2dc converter with a dc2dc converter of equal or greater ampacity.

What is the amp rating on the converter in your ac/dc distribution panel?

 

[John Frum]

This inverter/charger comes in all the popular system voltages .

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

 

[jameshowison]

I have the Victron 120v 48/3000/35-50 in a converted 30amp RV. It's working fine, but a few points to consider.

- It is hard to find 48v rated MEGA fuses in smaller enough sizes for the Lynx distributor. Victron makes "58v rated for 48v nominal systems" but not in small enough sizes for the MPPT (i.e., I don't think they make 40 amp or 30 amp MEGA fuses in the 58v for 48v systems). Conversely 24v uses exactly the same fuses as the 12v system. I ended up using Midnite DIN rail mounted circuit breakers for these smaller circuits, which gives convenient shut-offs as well, but takes up space and I worry that vibration might trip them (maybe happened once on a 5000m trip this summer, not entirely sure). You might be able to make this work with Midi fuses and a different distribution box. I would be happy to be wrong about this (new components come out all the time

- Some components are rated at 48v, but it's unclear whether they can be used in a 48v nominal system, which sees actual voltage up to 58 or even 60v. e.g., BlueSeas battery shut offs.

- The "PowerAssist" stuff (which uses battery power and the inverter to add power to a flakey shore-power connection, can output 50amps (that's the last 50 in the model name), so you have to turn that off and can't use it unless you rewire your RV from the inverter to the AC distribution box (probably need 6AWG and a 50 amp main breaker, rather than the 10AWG and 30amp main breaker that is there).

- Alternator charging is difficult, because there are few 12v --> 48v Dc to DC chargers (they exist, but Victron doesn't make one).

For me I had to have 48v since I have a direct 48v DC airconditioner (Hotspot), but if I didn't need to use 48v directly I would do this again in 24v.

 

[dab1294]

This inverter/charger comes in all the popular system voltages .

Yes! This was the one I was planning on.

Yes its additive and another battery will the problem.

Going back to this. Lets say I was firm on only needing the one battery. Are there other failsafes I could put it place to protect the battery? Can the inverter or shunt be programmed to not allow more than 200a discharge?

 

[John Frum]

Yes! This was the one I was planning on.


Going back to this. Lets say I was firm on only needing the one battery. Are there other failsafes I could put it place to protect the battery? Can the inverter or shunt be programmed to not allow more than 200a discharge?

If the grid is available you might try this feature

10. Description of Settings

www.victronenergy.com

If it is available in your version of the MP2.

 

[dab1294]

If the grid is available you might try this feature

10. Description of Settings

www.victronenergy.com

If it is available in your version of the MP2.

I will look into this more. I think I am leaning towards building a more traditional battery bank with SOK batteries now anyways. I've taken everyones advice and re-planned my system and this is what I have now: (IDK why it exported so crooked.. lol)

 

[jameshowison]

High level makes sense to me. Very similar to schematics from explorist.life: https://www.explorist.life/30a-camper-inverter-with-solar-and-alternator-charging-wiring-diagram/. They have some good designs and helpers for adding the battery shut-off and smart shunt to the Lynx.

The Victron inverter/chargers aren't protected against reversed polarity, so I put a hardwired surge protector thing in before the AC-in. https://hughesautoformers.com/product/pwd30-epo-h/. You might already have one that goes on the campsite pedestal.

The smart shunt also has a small DC positive power connection (with its own inline fuse). So that either doubles up on a distributor stud or you can feed it from the 12v RV distribution panel.

You will probably need a grounding bar for the inverter, the Lynx and the MPPT, there aren't enough spots on the negative on the Lynx distributor, but check the explorist.life drawings?

Are you sure that the 250/100 calls for a 150amp fuse? Seems high, but that's all in the manual and fuses definitely available

 

[jameshowison]

Have you done the Victron MPPT calculator here: https://www.victronenergy.com/mppt-calculator. the temperature coefficients can make a big difference to VOC. I'm guessing you are going with a 5S1P string because you only have space for 5 panels? And that is pushing you up to the 250voc MPPT? Otherwise a 3S2P would probably work with a 150/35 which is like close to a quarter of the price of the 250/100.

Actually that said, the 250/100 is way more amps than needed ... rock that victron calculator and save some bucks? If you can't get the VOC down, then at least go down to the 250/60, no?

 

[dab1294]

The smart shunt also has a small DC positive power connection (with its own inline fuse). So that either doubles up on a distributor stud or you can feed it from the 12v RV distribution panel.

Ah, I knew I forgot something!

The Victron inverter/chargers aren't protected against reversed polarity, so I put a hardwired surge protector thing in before the AC-in. https://hughesautoformers.com/product/pwd30-epo-h/. You might already have one that goes on the campsite pedestal.

My RV is going to be parts permanently in the AZ desert so the shore plug will likely only be used for a generator as needed, but I guess a little extra protection never hurts.

You will probably need a grounding bar for the inverter, the Lynx and the MPPT, there aren't enough spots on the negative on the Lynx distributor, but check the explorist.life drawings?

I'm really confused when it comes the grounding. The Explorist.Life diagram has a chassis ground off the Lynx's negative post. I've seen some people discussing an 8ft copper pole that you have to attach to. D you know any other good resources for info on grounding? Does the fact that I won't be plugging into shore make a difference?

 

[dab1294]

Actually that said, the 250/100 is way more amps than needed ... rock that victron calculator and save some bucks? If you can't get the VOC down, then at least go down to the 250/60, no?

My plan was to do it this way to allow me to add another 5 panel array on the ground (5s2p) if I want to in the future.

 

[jameshowison]

Ah, I knew I forgot something!



My RV is going to be parts permanently in the AZ desert so the shore plug will likely only be used for a generator as needed, but I guess a little extra protection never hurts.

Yeah, one can also just check the polarity of any random outlet, as long as one remembers. The Victron are fine with under/over voltage. We had the epo thing from before the conversion (where it protected against reversed polarity and under/over voltage), so stuck it inline.

I'm really confused when it comes the grounding. The Explorist.Life diagram has a chassis ground off the Lynx's negative post. I've seen some people discussing an 8ft copper pole that you have to attach to. D you know any other good resources for info on grounding? Does the fact that I won't be plugging into shore make a difference?

This helped me with thinking about RV system grounding: https://diysolarforum.com/resources/grounding-made-simpler-part-4-mobile-systems.159/

 

[jameshowison]

My plan was to do it this way to allow me to add another 5 panel array on the ground (5s2p) if I want to in the future.

Makes some sense, although it's also possible to "over-panel" the smaller victron MPPT. I haven't done this, but check out: https://community.victronenergy.com...ling-a-victron-charge-controller-and-the.html

As I understand it, the VOC is a hard limit (never exceed) but the amp output can "clip" so if you have more watts from the panels than the MPPT can output, it just clips. Given those peaks are very short (just in the very middle of the day) so much is lost in aggregate.

Another possibility is a second MPPT for a possible future array. Two smaller MPPT are less expensive (I think?) and maybe can also help with shading (ie RV in the shape, external panels in the sun), even better than parallel (again, I'm not super sure about that).

 

[dab1294]

This helped me with thinking about RV system grounding:

Thank you for this!

Another possibility is a second MPPT for a possible future array. Two smaller MPPT are less expensive (I think?) and maybe can also help with shading (ie RV in the shape, external panels in the sun), even better than parallel (again, I'm not super sure about that).

That makes sense! I think the smallest the MPPT calculator recommended though was the 250/85. (I am assuming a high Temp coefficient because it isn’t listed in the site and these panels are refurbs) Which still saves me a couple hundred bucks now, but I’m okay with spending a little more to keep my options open. (I have 10 panels to work with and haven’t fully decided how I’m going to position them)