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Need inverter that meets my systems requirements
#1
I could use some help finding an offgrid pure sine wave inverter.
Requirements;
Needs to operate at a voltage range up to 64v minimum
The low voltage that the inverter stops producing power needs to be adjustable
Has to supply 120v to loads

found this one (48v 1200w) that meets all of the requirements except it seems as if the voltage parameters for when inverter stops producing power is not adjustable, I thought all victrons parameters where adjustable with the dongle thing but I guess this one isn’t “smart”.. I’ve found many other brands like this that parameters aren’t adjustable but take over 64v and supply 110v...




Then I found this one (48v 1200w) and parameters are adjustable (or atleast should be adjustable for how much it costs) but for some reason the max volts it can handle was dropped to 62v (need 64v minimum)




This one (ms4048) will work (I think voltage shutoff is configurable) but it also had an ac charger (which I don’t need) and its expensive


The inverter needs to be able to run a small deep freezer and a small (300w) centrifugal blower fan and a grundfos water pump (roughly 100w)
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#2
I guess I could use an inverter like in the first pics (supplies 120v and will handle up to 68v) and since the parameters (doesn’t have communication port) aren’t adjustable, I would then install a separate low voltage disconnect on the battery to stop the inverter from producing power at desired low voltage of 58.6v, but then how would I get the battery to reconnect to the inverter when batteries reach full charge (64v)?
Really would be nice to not have to do all that and just have an inverter that could take atleast 64v, supplies 120v, and has adjustable recovery and shutdown parameters so I can set them for my 16s lithium ev battery bank
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#3
Ik no one has time these days with how busy we are but just know if I had the knowledge to help someone else in need I would. Thx
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#4
I think with the various time zones that most people who know the information needs to be taken into account. Also, this is a forum, not a phone call. Just because you post something, doesn't mean it should be responded to within a few hours.

And, very seriously, the world is dealing with a health crisis. So, I think it is more important that people focus on their health and those around them than on the forum.

Your post is only 11hrs old at this time, on a monday, with a health storm going around the world. Patience is required in times like these.
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#5
Agreed,. I’ve been not doing jobs for anyone lately due to the health crisis, so I have a lot of time to think about saving energy- getting some offgrid power going just in case it gets a lot worse,, this is kinda why I was trying to get a response quickly, but was not implying that it was taking to long to get a response.. I will patiently hope for help figuring this out soon
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#6
Why did you set your battery to 64v?? Prebuilt batteries?

Therese an reason why k state 14s is the most optimal when using 3.7v lithium cells. To me it looks you choosen a battery size that removed 95% of all inverters out there
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#7
Daromer,, yes they are prebuilt. I did end up excluding a lot of off grid inverters due to the battery voltage I chose. Reason; my grid tie inverters operating voltage is 45-90v. I chose a battery voltage that is in the middle of that so I didn’t need as many amps coming from my array which (I’m sure u know) lowers amperage heat lose and smaller wire sizes needed. Also the grid tie inverters I have work better and are more efficient using 64v (16s ev pack). When I chose this voltage I made sure there was offgrid inverters that could operate at this voltage, but I didn’t check to make sure the offgrid inverters low voltage shutoff was adjustable.
It think the bigger issue is that the inverter has to have adjustable low voltage shutoff, I havnt found many with that option. I have found many that will be able to use 64v. Some cut off at 62v but most (of the 48v inverters) I’ve seen can use 64v or more.. Alot off grid inverter manufacturers have a 48v option (usually also will operate at 64v) and will also produce 120v. So I’m looking for manufacturers-offgrid inverters that have adjustable parameters
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#8
(03-17-2020, 05:06 PM)Doin it Wrote: It think the bigger issue is that the inverter has to have adjustable low voltage shutoff, I havnt found many with that option. I have found many that will be able to use 64v. Some cut off at 62v but most (of the 48v inverters) I’ve seen are 64v or more.. Alot off grid inverter manufacturers have a 48v option (usually also will operate at 64v) and will also produce 120v. So I’m looking for manufacturers-offgrid inverters that have adjustable parameters
Controlling inverter on/off by battery voltage was always a key thing for me from the git-go.   I originally bought/used Samlex battery-guard(s) that let you choose from about 10 different ranges and they had one that was 24v/200a.  However, when I went to 48v system...   I also went to Midnite Classic controllers...  which happen to have auxiliary on/off and relay (your choice) based various things - one of which is battery voltage.  So now, I use this to turn on/off my inverters - and can do it thru the computer and custom software.       Another variation on this would be Batrium - the expansion board could be used for this as well.   There are other solutions as well. 

Ultimately, I like having a separate, customize-able, controllable on/off control based on battery voltage rather than try to tie it in with the inverter itself.
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#9
Offgridinthecity, I’m fairly certain it said in the manual that the outback charge controller I have has an aux that can be used for lvd. I think it would simplify the setup if the inverter has the adjustable low voltage shutoff capability.. my cheap gridtie inverters even have that capability... I guess if I can’t find an offgrid inverter reasonably priced that has the adjustment capabilities (low voltage shutoff) I need then I’ll use the outbacks aux and a relay.. I kinda checked into that,,, havnt yet been able to find a relay that can handle 64v 45amps.

Just found this, will it work for the relay that the outback triggers and handle battery voltage (64v) and amps 45



Or this one?
Doesn’t say dc tho, does that matter?
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#10
I tried SSR twice with no luck (they would switch on but not off) and finally settled on "Baomain JQX-62F-2C Coil Voltage DC 12V 80A DPDT Electronmagnetic Relay"    https://www.amazon.com/gp/product/B010L02RUO/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1  which I have direct experience will work at 45a level.   

However...
1)  Look at the last half of this recent thread discussing various relays - https://secondlifestorage.com/showthread...ight=relay   
and 
2) I outgrew the 45a relay as I'm up in 48v@250amp range now...   so I switched over to wiring into the inverter's on/off switch and bypassing the power leads.   This is typically a simple circuit close/open - e.g. trivial voltage / amps - and I think almost every inverter will have an on/off switch.

TMI - in AIMS case, they have an RJ45 jack for 'external control' and its really simple - short wires 3-5 for 'Rocker switch position on' or wires 5-7 for 'Rock switch power save on'.
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