New SRNE 30kw+ parallel build

[42OhmsPA]

Whoa, hang on. They have pre-built 280's? That on their main site?

USA STOCK Docan Assembled 51.2V 280Ah ESS Solar Grade 14kWh Plug & Play LiFePO4 Solar Energy Battery Pack – Floor mounted

Note:This link is only for orders within the Continental United States.You can easily track your order status on our website.After payment, we'll ship your order within 2weeks. It will be delivered to your door in 2-5 days via FedEx/UPS, with no tariffs.Orders for USA stock pick-up can only be made

www.docanpower.com

USA STOCK Docan Assembled 51.2V 280Ah/310Ah EV Grade A 14-15kWh Plug & Play LiFePO4 Solar Energy Battery Pack – Vertical Moveable

Note:This link is only for orders within the Continental United States.You can easily track your order status on our website.After payment, we'll ship your order within 1-5days It will be delivered to your door in 2-5 days via FedEx/UPS, with no tariffs.Orders for USA stock pick-up can only be made

www.docanpower.com

 

[1201]

Mentioned it another thread before posting in this thread.

Post in thread 'Fronius and SRNE'

Feb 26, 2025

The Fronius feeds into the main panel thus is on the Grid Input side of the SRNE6.5. This is not AC Coupling which is done either on the load side of the inverter or via a Gen Input or Aux, multipurpose port.

True, all power for the loads panel has to go thru the SRNE inverter. This is why I suggest looking at the HEBP which according to the manual can be set for "micro inverter input" on the generator port.

• Zwy

That also already exists on the hesp as well, correct?

 

[agtcovert]

That also already exists on the hesp as well, correct?

Yes, make sure you have the updated manual. The original version didn't mention it or it was added to later firmware.

I haven't had a reason to ask specifically, but at a high level my contact at Borick confirmed the functionality. I wish they had more details on it, in terms of parameters around frequency shifting, grid profiles, etc. Hoping to be able to check this out later this year. I have no immediate need for more gear, so I can wait for the HEBP (and perhaps divorce, lol!). I would like to try this out with some Hoymiles micros. Wouldn't be super expensive to get started with that. As long as it can form a 'microgrid' the Hoymiles (or whatever you'd integrate) that's not grid tied in my case, I'd consider it a win.

Of course, things get complicated if you're using the grid itself -- need an interconnect in that case.

 

[Zwy]

That also already exists on the hesp as well, correct?

I skimmed thru the manual and do not believe the HESP has that function. It would be best used as PV inverters connected on AC input side with grid power and all power has to go thru the inverter. From what I can see, the generator port is similar to grid bypass, it's just another source.

 

[Zwy]

It took me a while but I finally found it. I think.

"Micro inverter input"?

It's in the manual for both the hesp and hebp

Where did you find it in the HESP manual?

Edit: I found it in the US version manual, I was looking at Euro. So yes, the HESP has the same function as the HEBP.

 

[B-Mod]

I've been looking at Victron. The problem is I need at least 30kw capability (well now that I'm getting a Tesla more I think) with advice from folks here that my load should be <=50% of the inverter capacity. I also like that the SRNE is IP65 because my electrical room is also my water treatment room (just in case). But since right now I'm waiting for HEBPs to become available, I'm studying my load profile more. I will have some hot days next week to see what it looks like.

This system will be grid connected (already is) so will have that backup and then I have a 26kw Generac also. Net metering is fine financially but the grid here is so unreliable. I hate the constant outages, especially when it is hot and my solar array should be producing the most.

If your grid is so crappy with large surges and stuff. I would recommend you not connecting the grid to your inverters, instead use chargeverters to charge your batteries and keep the grid from wrecking your inverters. Just a thought.

 

[davewsail]

If your grid is so crappy with large surges and stuff. I would recommend you not connecting the grid to your inverters, instead use chargeverters to charge your batteries and keep the grid from wrecking your inverters. Just a thought.

Hmm. I hadn't thought about the grid issues possibly damaging the inverter itself. How much of a concern is this? I moved to Mexico from California and with PG&E fire precautions the grid was pretty bad there in fire season or when it was really hot. What is the major risk factor?

 

[1201]

Hmm. I hadn't thought about the grid issues possibly damaging the inverter itself. How much of a concern is this? I moved to Mexico from California and with PG&E fire precautions the grid was pretty bad there in fire season or when it was really hot. What is the major risk factor?

It wouldn't be a concern for me. A good inverter will disconnect from the grid almost instantaneously if there is a brownout.

You can set very strict voltage limits and if those limits are exceeded the inverter disconnects from the grid

 

[B-Mod]

It wouldn't be a concern for me. A good inverter will disconnect from the grid almost instantaneously if there is a brownout.

You can set very strict voltage limits and if those limits are exceeded the inverter disconnects from the grid

Not sure how bad the power is for the OP ster, but setting limits is not going to catch spilkes and sags. If my utility was that bad I would get rid of it or take action to avoid any issues from it. It is up to the OP ster to determine how much risk he wants to take.

 

[davewsail]

Not sure how bad the power is for the OP ster, but setting limits is not going to catch spilkes and sags. If my utility was that bad I would get rid of it or take action to avoid any issues from it. It is up to the OP ster to determine how much risk he wants to take.

I'm going to leave the grid connected as my baseline plan. I mean I'm running my house on it already with UPSs and surge protection boxes on my appliances. That is all sunk cost as it the grid connection. I'm actually surprised that my inverter minisplits seem to be very robust-- haven't had any issues on any of the 21 units in my house. Another benefit is that the startup current draw ramps up very slowly. I see these units as my riskier electronics in the house but so far, so good.

 

[davewsail]

When I buy the inverters, I'm going to get a spare. Initially I thought I'd just store it for a backup. But I was thinking, why not just hook it up also to give more headroom and it would allow me to add 2 more solar strings (because, why not?!). Aside from taking up some more wall space and more cabling/parts needed, is there a benefit I'm missing of having a spare in storage vs in-use? My thought process:

Pros of wiring in the spare:
1) More capacity/headroom
2) Spare already plugged-in if one fails
3) Dead on arrival / infant mortality discovered immediately
4) Less load on each inverter

Cons:
1) More cost/complexity of wiring it up
2) Warrantee period starts day 1 (not sure about this. If period starts on arrival or 1st use)
3) Use degradation (not sure about this either)

I know several of you have spares in storage so figured I ask for your thoughts.

 

[Zwy]

Wire gets expensive as you have to increase size, quite substantially. I did use 1AWG instead of 2AWG for the inverter AC output/input on the shop system and 250 feet of 1AWG cost me about $50 more plus more shipping cost due to weight. This was purchased online and shipped in. Box stores are not competitive on wire. I purchased from Nassau. Comparing 2/0 AWG copper to 2AWG copper, the price is 68% higher in order to cover the additional 63A adding another ASP inverter. That cost is there whether you have the unit turned on or off and if it is on, it is wearing out components plus using idle draw. No free lunch. Build the system according to what size is needed with some headroom for increases if one plans on adding more loads like mini split heat pumps. And yes, aluminum wire is cheaper per AWG but I only use aluminum for entrance cable. I prefer copper as aluminum cable wire ampacity is much lower. Ampacity of 2/0AWG copper is about the same as 4/0AWG aluminum. Have you ever worked with 4/0 aluminum? Not fun.

It may also require adding another breaker panel as the inverter output is increased as availability or cost of a larger backfed breaker increase. Or you have to add a transfer switch.

Part of the reason for spares is technology is growing fast in the solar arena and what you buy today might not be available a year or so down the road so it ends up a complete swap if an inverter fails. Take the LV6548 I have in the house. The LV6548 is still available but there have been some changes to the MPPT voltage input and other components and those might not be compatible. Plus, I have not had a single problem with the original firmware and a new unit might have incompatible firmware or updated firmware causes changes in operation.

 

[davewsail]

Wire gets expensive as you have to increase size, quite substantially. I did use 1AWG instead of 2AWG for the inverter AC output/input on the shop system and 250 feet of 1AWG cost me about $50 more plus more shipping cost due to weight. This was purchased online and shipped in. Box stores are not competitive on wire. I purchased from Nassau. Comparing 2/0 AWG copper to 2AWG copper, the price is 68% higher in order to cover the additional 63A adding another ASP inverter. That cost is there whether you have the unit turned on or off and if it is on, it is wearing out components plus using idle draw. No free lunch. Build the system according to what size is needed with some headroom for increases if one plans on adding more loads like mini split heat pumps. And yes, aluminum wire is cheaper per AWG but I only use aluminum for entrance cable. I prefer copper as aluminum cable wire ampacity is much lower. Ampacity of 2/0AWG copper is about the same as 4/0AWG aluminum. Have you ever worked with 4/0 aluminum? Not fun.

It may also require adding another breaker panel as the inverter output is increased as availability or cost of a larger backfed breaker increase. Or you have to add a transfer switch.

Part of the reason for spares is technology is growing fast in the solar arena and what you buy today might not be available a year or so down the road so it ends up a complete swap if an inverter fails. Take the LV6548 I have in the house. The LV6548 is still available but there have been some changes to the MPPT voltage input and other components and those might not be compatible. Plus, I have not had a single problem with the original firmware and a new unit might have incompatible firmware or updated firmware causes changes in operation.

Thank you for your thoughts. The main consideration seems to be additional cost and extra work. But I also did not consider idle power draw if on. I'll need to sharpen my pencil on this because I don't want to start changing out panels and such. I do plan on using copper, not aluminum. My friend builds houses and is always purchasing wire so I'm sure I can piggyback on his orders.

 

[Zwy]

If the inverters will be close to the loads panel, then upping wire size doesn't cost much. It will depend on panel location and how you intend to feed it power. Only one backfeed breaker with a generator interlock and that breaker has to be large enough. Sometimes a 200A transfer switch comes in handy. The HESP and soon to be released HEBP have built in output breakers and this would allow ganging using either a junction block or Polaris type connector. For the ASP and more than a pair of inverters, then one would install an output breaker under each inverter, then combine using a junction block or Polaris type connector. For a pair of ASP's, using a breaker panel like I showed in my shop build video works very well and allows for a pair of backfed breakers with hold down kits. If you need more than 10Kw sustained per leg, then either more ASP inverters or HESP/HEBP. Larger inverters usually have a higher idle draw, so keep that in mind.

 

[k490]

Compared to another 280Ah+ battery? I agree the gap is close on rackmount 100Ah, but 280's are still worth it IMO.

I'm comparing to the cost of building my own box out of metal. The cost of steel, disconnect, fuse, bulkheads, JK BMS, and hardware. Sure you could just buy a cheap heavy duty shelving system from Costco if you have the room I don't. Would still need a BMS, and wiring per 16 cells. This was the total price with EV grade 280s and a box. I will move my class T blue sea fuse and fuse holder to the the line between the inverter and my battery banks. I haven't had a chance to build the boxes yet need entire day where I can focus on it. I did weld up a heavy duty cart with 2200 lb casters I need to be able to roll the batteries around if needed.

 

[42OhmsPA]

I'm currently torn between building more or buying...

I'm waiting on DDP shipping costs and hopefully photos of the inside.
It was confirmed they all use JBD BMS, the 10.5kWh uses REPT cells the 5kWh and 14k.3Wh use EVE or REPT.

SE Series 48V Lithium Battery Energy Storage

SE Series 48V Lithium Battery Energy Storage

www.srnesolar.com

 

[Zwy]

If products ship by March 10th and are imported here by April 12th, the latest 10% tariff on China doesn't apply.

I'm not a fan of having cells lay on the sides.

 

[davewsail]

So it looks like I'll get my HEBPs well before my batteries. I'd like to hook them up and get everything running on the AC side even if I don't have batteries. Are there any reasons why I should not so this?

 

[agtcovert]

So it looks like I'll get my HEBPs well before my batteries. I'd like to hook them up and get everything running on the AC side even if I don't have batteries. Are there any reasons why I should not so this?

No.

Pictures please! I reached out to the same place you did, I have a quote 'on my desk' but I really would like to see the wiring compartment.

You can test an inverter with a bench power supply. Just set it to 51.2V or thereabouts. Only need 1A. It should power up. How I tested the ASPs last year.

Plus, you should verify they boot. For science!!

 

[davewsail]

No.

Pictures please! I reached out to the same place you did, I have a quote 'on my desk' but I really would like to see the wiring compartment.

You can test an inverter with a bench power supply. Just set it to 51.2V or thereabouts. Only need 1A. It should power up. How I tested the ASPs last year.

Plus, you should verify they boot. For science!!

I will definitely post pictures once I get things going. I'm waiting for shipment now and just trying to plan ahead.

 

[doing it different]

You can test an inverter with a bench power supply. Just set it to 51.2V or thereabouts. Only need 1A. It should power up. How I tested the ASPs last year.

Or steal every 12v battery you can find.. you only need 4 pc..
Cars, trucks, lawnmower, atv.

 

[davewsail]

So now that I've had my Tesla Model Y for a week, I see that I'm using 25+kwh daily charging it-- my wife drives a lot for the kids. So now I'm using like120-150kwh per day so my production will definitely be less than I consume. I can definitely add panels. I think I have 2 choices: 1) hook up my 4th HEBP with 2 more strings or 2) use one of my existing Growatt grid-tie inverters. Ideal would be to AC couple the Growatt on the load side of the HEBPs but I don't think that is possible. I know I can AC couple on the generator input but I plan on having my generator connected there.

If I hook up my spare HEBP, I no longer have a spare (I could order another one I guess). If I AC couple with my Growatt I would have a spare of both types of inverters. I was thinking of selling the Growatts but don't think I'd get much for them. Open for some input here.

 

[agtcovert]

So now that I've had my Tesla Model Y for a week, I see that I'm using 25+kwh daily charging it-- my wife drives a lot for the kids. So now I'm using like120-150kwh per day so my production will definitely be less than I consume. I can definitely add panels. I think I have 2 choices: 1) hook up my 4th HEBP with 2 more strings or 2) use one of my existing Growatt grid-tie inverters. Ideal would be to AC couple the Growatt on the load side of the HEBPs but I don't think that is possible. I know I can AC couple on the generator input but I plan on having my generator connected there.

If I hook up my spare HEBP, I no longer have a spare (I could order another one I guess). If I AC couple with my Growatt I would have a spare of both types of inverters. I was thinking of selling the Growatts but don't think I'd get much for them. Open for some input here.

I tend to like redundancy, so take that for what it's worth. If you can bake it in without spending more or put it towards panels, so much the better.

AC coupling, especially with the loads you're talking about, could make a lot of sense. It's also something I'd like to see done with one of the HExP inverters. I've exchanged some emails with a couple different reps and while they assure me it's there, they aren't offering much more than what's in the somewhat lacking documentation.

I don't think it'd be difficult to achieve, many people use Growatts to AC couple. The only thing that I wonder about is, in a parallel setup, do you wire that up to all inverters? (I'm thinking yes, since you'd want all the inverters to be able to 'use' the AC coupled power).

 

[davewsail]

I tend to like redundancy, so take that for what it's worth. If you can bake it in without spending more or put it towards panels, so much the better.

AC coupling, especially with the loads you're talking about, could make a lot of sense. It's also something I'd like to see done with one of the HExP inverters. I've exchanged some emails with a couple different reps and while they assure me it's there, they aren't offering much more than what's in the somewhat lacking documentation.

I don't think it'd be difficult to achieve, many people use Growatts to AC couple. The only thing that I wonder about is, in a parallel setup, do you wire that up to all inverters? (I'm thinking yes, since you'd want all the inverters to be able to 'use' the AC coupled power).

Thanks for your thoughts. I like redundancy too. And thinking more about it, in a multiple day grid down scenario, I'd be limiting my consumption and not be worrying about charging the EV anyway. I really just need to offset my normal life + EV consumption and AC coupling is just fine for that. I've got the roof space and all I need to do is mount some more panels.

 

[davewsail]

I don't think it'd be difficult to achieve, many people use Growatts to AC couple. The only thing that I wonder about is, in a parallel setup, do you wire that up to all inverters? (I'm thinking yes, since you'd want all the inverters to be able to 'use' the AC coupled power).

If I AC couple on the gen input of the HEBPs, I'd do it in parallel, but it is not clear if I can couple there with the generator itself. I have a 26kw Generac that will also be connected there. If I AC couple it, will the HEBPs ensure current flows into the inverters vs. back towards the Generac? The manual says nothing about this other that the gen input can be used to hook a generator, an AC coupled inverter or a smart load. My reading is that it is one of the three options but I'm a newb so have no idea. I'm envisioning the scenario where the Growatt is sending power and obviously I want current to flow to the HEBPs to power loads or charge battery, not to the generator. I need to ask SRNE but figured someone here might have some idea. Right now the geni output goes through an ATS upon grid down so no other current source. I want to leave that ATS as is because I also plan on a downstream manual transfer switch if my HEBPs fail so I can quickly switch back to grid with generator backup (my current configuration).

The manual says nothing about AC coupling on the load side of the HEBPs so I'm guessing that is not an option. Worst case is I AC couple on the grid input with net metering. Not what I'd like to do but I know that will work.