What do I need

[philatio]

Hoping to get some direction here.

I have a grid tied system I do not touch, and an off grid system conected to a switched neutral critical loads panel due to the ng bond created when running my MPP Solar LVX6048 off batteries.

I am currently changing batteries from the main, and a battery changer. It still takes a couple days to charge the batteries (6 x EG4-LL v1) and I want to reduce this time frame.

It's time to add some solar. I am experimenting/learning and don't want to void the warranty on my professionally installed system so I am keeping the separate.

This pic show the basic setup minus the AC input into the inverter from the main.


What do I need to add say 4 solar panels to this set up. I don't need info on the panels as the LVX6048 will take 450V and max 27A.

I want to know about grounding say 4 panels (in series). Will adding another breaker to the disconnect that the changer is connected to suffice for a disconnect.

Do I need to fuse this small amount of panels.

All this is being done while I decide which hybrid inverter will replace my grid tied SMA Sunny Boy 7.7

Thanks in advance

 

[MaikaiLifeDIY]

I think you're asking how to hook up 4 series panels to your LVX6048 inverter. If so, when you add panels in series voltage increases, when in parallel amperage increases. If you're going to add these 4 panels in series make sure their combined voltage doesn't exceed your inverters maximum on the MPPT input.

You're inverter is already hooked to the batteries, so it will simply push the solar energy through to the batteries the same way you have your charger connected.

For grounding you never ground the panels to your inverter, you run a separate earth ground to discharge static, or possibly a lightning strike.

Be careful your charger and your solar are not charging at the same time or at least are charging at the same voltage so that you don't have current pushed to either charge source and instead only pushed to the batteries.

You should always add a disconnect for your panels to your MPPT, I typically use high-voltage breakers or switches because fuses can't be turned off/on safely when you need to disconnect your panels.

Am I understanding your question correctly?

 

[Mattb4]

4 panels might not provide sufficient voltage even when wired in series for your AIO. So yes you do need to know the panels specifications.

 

[timselectric]

Yes, you absolutely need to ground the panel frames and any metal racking.
NEC requires that you connect them to your LVX6048.
But any part of your existing grounding system is fine.
Do not connect them to a separate ground rod. That's not grounding, that's just earthing.
Grounding is for protection against people getting shocked when touching them. And will also discharge static.
Lighting protection is a completely different system.

 

[philatio]

Thanks for the feedback everyone.

I think you're asking how to hook up 4 series panels to your LVX6048 inverter. If so, when you add panels in series voltage increases, when in parallel amperage increases. If you're going to add these 4 panels in series make sure their combined voltage doesn't exceed your inverters maximum on the MPPT input.

4 panels might not provide sufficient voltage even when wired in series for your AIO. So yes you do need to know the panels specifications.

I am looking at a few used 390 watt panels: VOC = 44.1V x 4 = 176V. Well within the 450V limit of the inverter. Amps, 10 something. Well within the max 27 of the LVX6048. I have no issues figuring out VOC/AMPS Series/Parallel etc for the inverter.

Be careful your charger and your solar are not charging at the same time or at least are charging at the same voltage so that you don't have current pushed to either charge source and instead only pushed to the batteries.

Good information. Thank you. I would have made this mistake. The charger is the EG4 18amp 48V charger fro SS. By current am I safe in assuming you mean amps? Id that's the case there is no way to get both current outputs the same as max amps for the inverter is 27a I believe.

For grounding you never ground the panels to your inverter, you run a separate earth ground to discharge static, or possibly a lightning strike.

This seems to conflict with @timselectric 's response

NEC requires that you connect them to your LVX6048.
But any part of your existing grounding system is fine.

As this is not a permanent install, more so for learning I was really hoping to do as Will has done in many videos and just lay them out on the ground in my yard.

 

[400bird]

Thanks for the feedback everyone.


I am looking at a few used 390 watt panels: VOC = 44.1V x 4 = 176V. Well within the 450V limit of the inverter. Amps, 10 something. Well within the max 27 of the LVX6048. I have no issues figuring out VOC/AMPS Series/Parallel etc for the inverter.

You know there is a minimum voltage too, right?
That's what Mattb4 was referring to in post #3

 

[philatio]

You know there is a minimum voltage too, right?
That's what Mattb4 was referring to in post #3

Thank you. Yes, understood. But I am ok in that regard too.

 

[1201]

I was going to suggest- why not just use utility mode on your inverter and have it charge the battery and then just start drawing from utility instead of hitting your batteries. But then I saw them you want to learn the pv side so they kinda eliminates my idea from contention ?

 

[philatio]

I was going to suggest- why not just use utility mode on your inverter and have it charge the battery and then just start drawing from utility instead of hitting your batteries. But then I saw them you want to learn the pv side so they kinda eliminates my idea from contention ?

It's not just learning the PV side, but increase the battery charge rate. The AC in on the inverter is also used in bypass mode when batteries need to charge. In Texas it is a balancing act. The AC (cooling not power) runs almost constantly with the base and the ac running draws between 3.5 & 4 kw.

That doesn't leave much head room to also charge the batteries which is why I also use the battery charger. This is just a backup system.

I keep nickel and dimeing myself, for example I am considering a chargeverter, but there is definitely an 18kpv or 15k in my future.

 

[1201]

It's not just learning the PV side, but increase the battery charge rate. The AC in on the inverter is also used in bypass mode when batteries need to charge. In Texas it is a balancing act. The AC (cooling not power) runs almost constantly with the base and the ac running draws between 3.5 & 4 kw.

That doesn't leave much head room to also charge the batteries which is why I also use the battery charger. This is just a backup system.

I keep nickel and dimeing myself, for example I am considering a chargeverter, but there is definitely an 18kpv or 15k in my future.

If you set the inverter to uti mode it just passes through the AC in to power the loads unless there is an outage -you never even hit the batteries

 

[SamDeleted]

Remember MPPTs have a minimum start up voltage, sometimes up to 250v

Make sure your array exceeds that voltage both summer and winter

 

[timselectric]

As this is not a permanent install, more so for learning I was really hoping to do as Will has done in many videos and just lay them out on the ground in my yard.

I've done a lot of "unsafe" things, in the name of temporary.
If you are the only person who will ever be around them. Then, you just need to be aware of the Hazzard.
But if others will have access to the Hazzard. I would be a lot more inclined to make sure that Noone could get hurt.