Which rack mount batteries support this protocol natively?1) pylontech protocol canbus
That is equipment dependent.2) 13ms, what is the max before issues?
Don't we all.3) That's a question all of us would like to know the answer to.
IMO. Thinking about it, if I were building a solar system for someone who was remote and the system must be reliable because the that person wasn't great with electrical stuff, I'd probably do something like SolArk or MidNite, not necessarily the new to be out MidNite aio, but their proven separates.Which rack mount batteries support this protocol natively?
Battery protocols are "just" software, so perhaps future firmware updates can enlarge the options?
That is equipment dependent.
I would expect anything over 20 ms to be a problem. Under 10 ms should be fine. 13 ms is probably okay.
Many power supplies are rated for about 10 ms hold up time (how long they can provide power with loss of AC input) at rated load, but few are run right at the max rating.
Don't we all.
Mike C.
Sol-Ark unit that fits the specs is Sol-Ark 15K-2P-N. The 12K is only 9 KW AC output despite the "12K' in the name. Cost is $7000.IMO. Thinking about it, if I were building a solar system for someone who was remote and the system must be reliable because the that person wasn't great with electrical stuff, I'd probably do something like SolArk or MidNite, not necessarily the new to be out MidNite aio, but their proven separates.
SRNE ASF48100U200-H. Only has 2 MPPT which won't match my array. 2 strings is either too much voltage, or doubling a string is too much current for the ratings. Also, max PV array size is 11 KW, my array will be 11.7 KW. It just isn't a fit.The new srne is now out and parallel capable, check out https://diysolarforum.com/threads/4-mwh-srne-asf48100u200-h-10kw.67809/
The difference between $2200 and $7000 is very significant. Maybe the $2200 unit is the wrong one, but if so, that's less than 15% of the system cost, so I can replace it. If it works, that's dandy, if it doesn't, less money was risked. Based on Ian's videos, it does work at least to some degree.It sounds like you are heavily weighting price when it comes to price/reliability.
Wish the same.Been running SolarAssistant for 2+ years and do not plan on using whatever app comes with the nhx. Check out the SA website https://solar-assistant.io/ Wish their website listed all the functions available with xxx inverter using SA.
SRNE ASF48100U200-H. Only has 2 MPPT which won't match my array. 2 strings is either too much voltage, or doubling a string is too much current for the ratings. Also, max PV array size is 11 KW, my array will be 11.7 KW. It just isn't a fit.
I can't find anything SRNE makes that fits my use case.
The difference between $2200 and $7000 is very significant. Maybe the $2200 unit is the wrong one, but if so, that's less than 15% of the system cost, so I can replace it. If it works, that's dandy, if it doesn't, less money was risked. Based on Ian's videos, it does work at least to some degree.
My parents are funding the system, they are retirees, so making the system inexpensive and with a short payback period is part of the objective here.
I run without comms, I find it unnecessary.Wish the same.
It is just so hard to get definitive information about what works with what. Will battery X work with inverter Y (with BMS comms)? What level of remote control will SA provide with inverter Y? You just don't know.
Mike C.
my array is planned as 36-370w panels into a single SRNE 10kw.SRNE ASF48100U200-H. Only has 2 MPPT which won't match my array. 2 strings is either too much voltage, or doubling a string is too much current for the ratings. Also, max PV array size is 11 KW, my array will be 11.7 KW. It just isn't a fit.
And extra wiring, space, breakers, panels, etc. Buying a second inverter just to get 2 MPPTs sounds illogical when I can buy one $2200 inverter with 4 MPPT that match my array plans, so why not do that?You purchase a pair for 20Kw total and you get 4 MPPT's.
That's the hill billy solution to battery protocols, I suppose.I run without comms, I find it unnecessary.
The panel rated current is ~13 amps, so double that is over the 22 amp MPPT spec on the SRNE.my array is planned as 36-370w panels into a single SRNE 10kw.
I don’t know your panel specs but at 9s2p I’m at (see pic) per input
Your post implies MPPT behavior I was not aware of, that is, the MPPT will back off max power if the current limit of the input is being reached. Is that how they operate or do they only adjust to the max power even if that is over the input current limit?Which only over panels me by 1100w per input which will only clip on perfect days, otherwise it should be a non issue.
And extra wiring, space, breakers, panels, etc. Buying a second inverter just to get 2 MPPTs sounds illogical when I can buy one $2200 inverter with 4 MPPT that match my array plans, so why not do that?
That's the hill billy solution to battery protocols, I suppose.
Well, I guess I'm done with this discussion.I would prefer the system have battery comms and one can track the battery condition in the inverter. There are possible issues that could be problematic without comms, like one pack shuts down and the inverter doesn't know about it.
Mike C.
Yes, the mppt limits production and the reason you can safely overpanel most mppts, to an extent. Many people overpanel so they can harvest more on cloudy days/winter knowing they will loose some production on sunny days as the mppt clips.Your post implies MPPT behavior I was not aware of, that is, the MPPT will back off max power if the current limit of the input is being reached. Is that how they operate or do they only adjust to the max power even if that is over the input current limit?
Mike C.
If your at 13a per string then your max 26a. So you may see a bit more clipping than I would. But that is correct the MPPT will “throttle” input to not exceed 22aThe panel rated current is ~13 amps, so double that is over the 22 amp MPPT spec on the SRNE.
With 30 panels of 390 W, you would need to make 10s2p for one MPPT, and 10s1p for the other. Doable, I suppose, but the double input will clip when you get full sun.
Your post implies MPPT behavior I was not aware of, that is, the MPPT will back off max power if the current limit of the input is being reached. Is that how they operate or do they only adjust to the max power even if that is over the input current limit?
Mike C.
7s2p with 370W panels on MPPT1 (just over 22A max) , 9s2p with 315W panels on MPPT2 (just over the 5500W max). Voltage is happy and well within theIf your at 13a per string then your max 26a. So you may see a bit more clipping than I would. But that is correct the MPPT will “throttle” input to not exceed 22a
You could run 7s2p into each input and use 28 of 30 panels
I can appreciate the comfort of having something that has worked for you.The NHX looks promising but I'm almost certain I'm sticking with the parallel version of what I'm running for the next upgrade.
Okay, so if battery comms are not a thing you need, then maybe you can buy cheaper batteries that lack comms altogether.No comms between batteries and inverter.
The SRNE HES / HESP is sealed(IP65); the ASF / ASP is not sealed. They seem to have a nice factory as well.I can appreciate the comfort of having something that has worked for you.
One of my misgivings with the SRNE inverter is that it isn't sealed. The Amensolar, Megarevo, Sungold inverter is sealed, IP65. When it is mounted in the humid dusty garage in Florida, having the fans not drag moisture and dust over the high voltage electronics is a good idea. I would judge the sealed unit is going to have less long term problems for that reason. Everything in Florida corrodes in the humid and salty air.
I did find a video of this style of inverter being built:
It appears to be the slightly older version than what is sold now (flat face panels instead of chamfered). The video is fairly impressive, a modern process. What I can see of the design looks well done.
Inside showing heat transfer pads:
View attachment 210452
Main inverter power board:
View attachment 210453
Putting in the relay and control board:
View attachment 210454
Automated test and burn in:
View attachment 210455
The production process feels first rate to me. That doesn't mean it is a good design, however, but it is hopeful.
Mike C.
I want and need battery comms, that's why my BMS's talk to Solar Assistant. I don't want or need inverter / battery comms. I use appropriate safe voltages and tail current.Okay, so if battery comms are not a thing you need, then maybe you can buy cheaper batteries that lack comms altogether.
For ~$4000 with shipping and BMS's you can get ~31kWh and build your own that are easily serviceable.For example, 4 of these in series:
View attachment 210461
$900 each. For $3600, you get 51.2V, 400 AH, 20.5 KWH. Free shipping, which is non trivial with ~90 lbs batteries. To replicate this with rack mounts, it would cost about $5000.
Haha, lots. Mainly keeping the 12V packs in balance, not being able to service them and not being able to monitor cells.What is the downside to that plan?
If you believe this video, those units produced 433 AH at about 0.1 C discharge.
Mike C.