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Sunny Island 6048 time controlled operation

lfw2069

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Have a quad stack SI 6048 US (1 Master + 3 slaves) AC + PV coupled system. I want to be able to program the Master to go into battery mode every day from 12AM to 9AM as I have enough battery storage to run the house without grid supply power. Can anybody tell me if I can use parameters 500# 500.04 InvTmOpStrTm – 500.05 InvTmOpRnTm – 500.06 InvTmOpCyc OR TmCtl.IsOn - TmCtl.RptCyc - TmCtl.StrTm to accomplish this task? Or if I need to install a contactor to disconnect from grid and use Relay 1 or 2 to control the solenoid.

Best,

RR
 
I'm not an expert with the timer functions as I don't use any of them.. that said, from reading the manual, it doesn't look like those functions will cut out your grid power.. From what I can tell, they cut out all power by putting the SI into standby mode.

Two work arounds might be available..
1) Your suggestion to put a contactor on the grid lines

2) (I say this with caution because you'll have to research it) You might be able to trick the SI into thinking the grid is a generator. You DO NOT want to make it think the generator is the grid because of all the tight frequency/voltage tolerances, plus the reverse current issue since pumping current back into your genset would be very bad..
But I don't see any obvious issues with making the SI think the grid is a generator.. in which case, you could then play with the generator timer functions and set the timers so the generator (the grid actually), is only allowed to be used during certain times that you specify.

I'm not sure if #2 will work, its just an idea, but I do know you can make the Sunny Island think the grid is just a generator because I've done it. The Sunny Islands must have been thinking "Wow, that's one hell of a good generator this guy has!" LOL
 
I'm curious about the parameter options that might accomplish this.
Obviously, you could disconnect from grid by relay, reconnect at the end of the time period or if SoC drops too low.
Ideally, just software options. One way could be to set a lower target battery voltage so it starts inverting, same as it would if DC coupled SCC drove battery to a higher voltage. People have experimented with using Sunny Island for grid support, but I don't have any details.

Run off battery at night? That's when grid power is usually cheapest. I would have thought you might want to disconnector or otherwise draw down battery during hours of peak rates.
Do you have a battery which supports sufficient cycle life that it won't wear out too soon?
What is the cost per kWh to cycle your battery until end of life? Most batteries I've done the math for cost more than the spread between peak and off-peak rates. The exception is DIY batteries, or cheap commercially assembled re-purposed batteries.
 
Thank you all, I think I will put a NC contactor on the grid lines and control the solenoid via a smart switch which I can control via the home kit app and go into battery mode at the desired time. The other issue that I have is that the installer did not leave a bypass switch to bypass the SI completely, I have been looking at a solution and found the MIDNITE SOLAR MNE250SMA-QUAD MSTR-E E-PANEL but since I have a Master and 3 slaves it seems that I will need to add 3 extra MNE250SMA slave panels and the solution seems expensive. Any other suggestions? The installer suggested installing a 3 position 200 AMP double-throw switch but I think it will look awful on my nice SMA system. Regarding batteries, I have the SI coupled to 10 simplphi 48 Volts 3.8 pictures attached.
 

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Thank you all, I think I will put a NC contactor on the grid lines and control the solenoid via a smart switch which I can control via the home kit app and go into battery mode at the desired time. The other issue that I have is that the installer did not leave a bypass switch to bypass the SI completely, I have been looking at a solution and found the MIDNITE SOLAR MNE250SMA-QUAD MSTR-E E-PANEL but since I have a Master and 3 slaves it seems that I will need to add 3 extra MNE250SMA slave panels and the solution seems expensive. Any other suggestions? The installer suggested installing a 3 position 200 AMP double-throw switch but I think it will look awful on my nice SMA system. Regarding batteries, I have the SI coupled to 10 simplphi 48 Volts 3.8 pictures attached.
Wow.. that even looks expensive.
 
I have a bypass for my 2s2p Sunny Island.
It is a Square-D QO breaker panel, with interlock between main breaker and adjacent backfed breaker. Each pole carries the combined current of paralleled Sunny Islands.

If you have Sunny Islands in parallel feeding grid through to loads (or from Sunny Boys), what OCP devices do you use on their input and output?
I initially used QO branch circuit breakers (for each Sunny Island), but resistance different between them so much current was imbalanced 3:1
I now use 2 pole 63A Schneider DIN-mount breakers, which let current match pretty much perfectly.

What is the expected cycle life of your Simplifi battery?
What is the cost per kWh stored, if cycled to end of life?

You plan to disconnect grid input based on your home app - I suggest wiring the control through a relay in SI for "Generator Start". If SI decides it wants generator due to low battery, this will reconnect grid.
 
Thanks, I had built a parallel transfer switch to transfer to the generator when the grid was not present with two parallel contactors but I run into a similar problem which resulted in the SI not qualifying the grid and getting anti island errors 331 and 333. It drove me crazy for 3 days until I bypassed them to test and the problem went away. The issue did not happen immediately, it started happening a few months after the units were commissioned. I am getting a Generac transfer and connecting it directly after the FPL meter.

Which interlock did you install? I also used a Square-D QO breaker panel.

I am looking for answers regarding the battery life and cost.
 
Thanks, I had built a parallel transfer switch to transfer to the generator when the grid was not present with two parallel contactors but I run into a similar problem which resulted in the SI not qualifying the grid and getting anti island errors 331 and 333. It drove me crazy for 3 days until I bypassed them to test and the problem went away. The issue did not happen immediately, it started happening a few months after the units were commissioned. I am getting a Generac transfer and connecting it directly after the FPL meter.

Which interlock did you install? I also used a Square-D QO breaker panel.

I am looking for answers regarding the battery life and cost.
Make sure that any transfer switch you install has a timer delay built in. There are specific warnings within the SI Manual about rapid switching causing damage to the SI inverters.

I can tell you right now that Hedges made a comment somewhere that there is no such thing as a battery beating the grid power economics, and that he is spot on.
If you're doing some kind of load shifting, its going to cost you more in battery wear and tear than it would to just pay the POCO. In order to beat the POCO, you'd have to find a good deal on bat cells and build your own bank.. and even then, the difference isn't going to be much.

The best solution for expensive POCO bills is to install solar panels.
 
Make sure that any transfer switch you install has a timer delay built in. There are specific warnings within the SI Manual about rapid switching causing damage to the SI inverters.

I can tell you right now that Hedges made a comment somewhere that there is no such thing as a battery beating the grid power economics, and that he is spot on.
If you're doing some kind of load shifting, its going to cost you more in battery wear and tear than it would to just pay the POCO. In order to beat the POCO, you'd have to find a good deal on bat cells and build your own bank.. and even then, the difference isn't going to be much.

The best solution for expensive POCO bills is to install solar panels.
Correct, I have 3 SB 7.0 connected to 3 PV arrays. At the moment I just want to install the bypass.
 
Correct, I have 3 SB 7.0 connected to 3 PV arrays. At the moment I just want to install the bypass.
Wow. that's some serious power..

I have two SB6.0's and switched over to electric heating just to suck up some of the juice...
 
I actually have a couple of interlocks.

I got a QO 100A/30A generator input panel, which has those two branch circuit breakers side by side. I replaced them with 70A/70A to feed my house from either SI (PV panel & load-shed relay) or grid (main panel). House is automatically on SI as UPS, but if that fails just a flip of breakers.

Main panel is outdoor QO 225A with 200A main and 100A backfeed (which also goes to PV panel and load-shed relay.) This allows me to manually feed garage/shop from SI.

I have another for the indoor QO 125A panel, but not installed yet.

SMA's manuals say transfer of inverter input from one AC source to another should have 5 seconds off in between, to ensure inverter shuts off.

My math on batteries says AGM costs $0.50/kWh, FLA $0.25, commercial lithium $0.50, DIY lithium $0.05; some other brands of lithium are at low price points, might make financial sense.
A life test of many lithium batteries had 95% fail.
I would consider DIY LiFePO4 if I was going to arbitrage power rates.

Instead, I think I'm better off feeding utility 3x the power in the morning at $0.15/kWh so I can enjoy a kWh in late afternoon priced at $0.50
I think extra PV is cheaper than storing in batteries, even if some batteries are cheaper than utility rates.
 
I'm not an expert with the timer functions as I don't use any of them.. that said, from reading the manual, it doesn't look like those functions will cut out your grid power.. From what I can tell, they cut out all power by putting the SI into standby mode.

Two work arounds might be available..
1) Your suggestion to put a contactor on the grid lines

2) (I say this with caution because you'll have to research it) You might be able to trick the SI into thinking the grid is a generator. You DO NOT want to make it think the generator is the grid because of all the tight frequency/voltage tolerances, plus the reverse current issue since pumping current back into your genset would be very bad..
But I don't see any obvious issues with making the SI think the grid is a generator.. in which case, you could then play with the generator timer functions and set the timers so the generator (the grid actually), is only allowed to be used during certain times that you specify.

I'm not sure if #2 will work, its just an idea, but I do know you can make the Sunny Island think the grid is just a generator because I've done it. The Sunny Islands must have been thinking "Wow, that's one hell of a good generator this guy has!" LOL
MurphyGuy: Don't want to hijack this thread, but could that same principle be used to start up and use a phase inverter off grid?
 
MurphyGuy: Don't want to hijack this thread, but could that same principle be used to start up and use a phase inverter off grid?
I don't think so.. Timer functions for generator activation also come with safety parameters that create error codes if the SI's don't detect the generator running. If I read what you're asking correctly.

What are you trying to do with the phase inverter? The SI's do have a load dumping feature that allows you to send extra energy to do some other work...
 
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