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Sol-Ark 12K plus secondary charge controller

mvonw

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Does anyone have any experience/advice/cautions about using a secondary charge controller on the same battery bank as the Sol-Ark?
I was hoping that it would be possible to connect something like a Schneider 100A mppt to the same bus bar as the Sol Ark. I know they would need to both be programmed to the same the voltage cutoffs, etc, but I wanted to see if this was even feasible/doable.

I called Sol Ark and they said to buy a second Sol-Ark and parallel them.
 
Does anyone have any experience/advice/cautions about using a secondary charge controller on the same battery bank as the Sol-Ark?
I was hoping that it would be possible to connect something like a Schneider 100A mppt to the same bus bar as the Sol Ark. I know they would need to both be programmed to the same the voltage cutoffs, etc, but I wanted to see if this was even feasible/doable.

I called Sol Ark and they said to buy a second Sol-Ark and parallel them.
Probably the best way to go about it is to have 2 Sol-Arks but that would be an expensive battery charger.

I don’t have my inverters talking to my BMS.
Just use batt-v.

I have in the past used another charger to charge batteries at the same time as the inverter and it didn’t care.

The Sol-Ark has the ability if grid connected to push 185 amps to the battery.

How many amps are you wanting to put in?
 
Probably the best way to go about it is to have 2 Sol-Arks but that would be an expensive battery charger.

I don’t have my inverters talking to my BMS.
Just use batt-v.

I have in the past used another charger to charge batteries at the same time as the inverter and it didn’t care.

The Sol-Ark has the ability if grid connected to push 185 amps to the battery.

How many amps are you wanting to put in?
It's the Sol Ark's voltage limits on the MPPT's that I'm concerned about. I'm going to be connecting two strings @425vdc (11.2amps) into each of the Sol Ark's Mppts,. The Sol Ark has 500 vdc maximum, but I need to account for temperature compensation on the panels. I have more space on my ground mount and I was hoping to get a few more panels to better deal with some shading issues...
 
It's the Sol Ark's voltage limits on the MPPT's that I'm concerned about. I'm going to be connecting two strings @425vdc (11.2amps) into each of the Sol Ark's Mppts,. The Sol Ark has 500 vdc maximum, but I need to account for temperature compensation on the panels. I have more space on my ground mount and I was hoping to get a few more panels to better deal with some shading issues...
Use the Solar panel Calculator.

 
Does anyone have any experience/advice/cautions about using a secondary charge controller on the same battery bank as the Sol-Ark?
I was hoping that it would be possible to connect something like a Schneider 100A mppt to the same bus bar as the Sol Ark. I know they would need to both be programmed to the same the voltage cutoffs, etc, but I wanted to see if this was even feasible/doable.

I called Sol Ark and they said to buy a second Sol-Ark and parallel them.
I’m actually thinking of doing the same thing with my 8K. Was planning on using secondary charge controller and setting the voltages lower on the secondary controller than the sol-ark. I will let the sol-ark do the absorb/top balance phase currently set at 56vdc. Would probably set the secondary controller at 54.4vdc. Would have to play around with the setup to fine tune. Still haven’t decided on charge control but researching at the moment, really hoping to find an quality controller with dual mppt. Would tie into my buss bar through a dc combiner and breaker. Another set of PV disconnects and SPDs so kinda $$.

Have also considered just paralleling another 2000 watt array into my existing 2000 watt and facing it SW. It would be cheaper and easier to do but I don’t know if I would net enough extra power being paralleled since the existing array would start to shade out before the proposed SW array would be be in full sun from 2:30 to 5:00. I have the panels already and a ground mount. Seems the most plausible.

If I go with another controller I was planning to do an east array of 800 watts and west array of 800 watts. My summer capture window on existing south arrays is only 4.5 hours. 11-3:30 peak power no shading. Mppt#1 is 2000 watts and Mppt#2 is 1600 watts array. But I have locations that can get another few hours E and W to help out. West facing will net from 2:00 to 6:00. East will net from 9:00 to 2:00. Mountainous terrain and mature forests have their challenges with laying out huge arrays.
 
I have more space on my ground mount and I was hoping to get a few more panels to better deal with some shading issues..
Another alternative for just a few panels would be micro inverters AC coupled if you just want to harvest more power.
 
I’m actually thinking of doing the same thing with my 8K. Was planning on using secondary charge controller and setting the voltages lower on the secondary controller than the sol-ark. I will let the sol-ark do the absorb/top balance phase currently set at 56vdc. Would probably set the secondary controller at 54.4vdc. Would have to play around with the setup to fine tune. Still haven’t decided on charge control but researching at the moment, really hoping to find an quality controller with dual mppt. Would tie into my buss bar through a dc combiner and breaker. Another set of PV disconnects and SPDs so kinda $$.

Have also considered just paralleling another 2000 watt array into my existing 2000 watt and facing it SW. It would be cheaper and easier to do but I don’t know if I would net enough extra power being paralleled since the existing array would start to shade out before the proposed SW array would be be in full sun from 2:30 to 5:00. I have the panels already and a ground mount. Seems the most plausible.

If I go with another controller I was planning to do an east array of 800 watts and west array of 800 watts. My summer capture window on existing south arrays is only 4.5 hours. 11-3:30 peak power no shading. Mppt#1 is 2000 watts and Mppt#2 is 1600 watts array. But I have locations that can get another few hours E and W to help out. West facing will net from 2:00 to 6:00. East will net from 9:00 to 2:00. Mountainous terrain and mature forests have their challenges with laying out huge arrays.
I contacted Sol Ark support and they recommended setting the Sol Ark bulk and equalization voltage to zero, and only set the float voltage on the Sol Ark. The second charge controller would handle bulk and and equalization. They said this was necessary so the the the two mppt's don't 'fight' each other..

I actually realized in researching this that the Sol Ark can take 500 volt in each of it's 4 PV inputs (2 mppts). I misinterpreted the documentation thinking that the the 500 volt limit was per mppt, not mppt input. Realizing that, I'm now pretty sure I don't currently need the second controller.

But, given that I'm trenching 300 ft, I'm going to run extra pairs of cables for future use for a SW facing array...
 
I am thinking about this vs buying an additional Sol-Ark. Sol-Ark said micro inverters to GEN (AC Couple) would have to go for load or grid. I don’t sell back to grid, so want to store excess PV production to batteries.
 
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am thinking about this vs buying an additional Sol-Ark. Sol-Ark said micro inverters to GEN (AC Couple) would have to go for load or grid. I don’t sell back to grid, so what to store excess PV production to batteries.
I just installed a SolArk and have my micros connected to the Gen port. I am unclear about whether the SolArk can limit the export of AC coupled inverters. i know it can limit the export of DC coupled inverters. My theory is based on the fact that when connected to the grid, the AC signal passes through to the Gen Port and there is no way to adjust frequency to limit the output of the AC coupled solar when connected to the grid.
 
I just installed a SolArk and have my micros connected to the Gen port. I am unclear about whether the SolArk can limit the export of AC coupled inverters. i know it can limit the export of DC coupled inverters. My theory is based on the fact that when connected to the grid, the AC signal passes through to the Gen Port and there is no way to adjust frequency to limit the output of the AC coupled solar when connected to the grid.

Sol-Ark told me excess PV on GEN (AC coupled) would backfeed to grid if not used up in AC load.
 
Sol-Ark told me excess PV on GEN (AC coupled) would backfeed to grid if not used up in AC load.
As far as I know, there is not any way to have a SolArk limit export of AC coupled inverters. I am adding more micros and do not want to go over the limit in my NEM agreement so I am looking into doing that from the Envoy, which controls the Enphase micros. I will report if I find a solution. I already have the external CTs attached to the Envoy.
 
Sol-Ark told me excess PV on GEN (AC coupled) would backfeed to grid if not used up in AC load.
What if you are not connected to the grid ?

What does it do with the power if it can’t be used and no grid to backfeed?
 
Found this from Sol Ark regarding the 12k the 15k will do 19k of AC coupling;
 
Does anyone have any experience/advice/cautions about using a secondary charge controller on the same battery bank as the Sol-Ark?
I was hoping that it would be possible to connect something like a Schneider 100A mppt to the same bus bar as the Sol Ark. I know they would need to both be programmed to the same the voltage cutoffs, etc, but I wanted to see if this was even feasible/doable.

I called Sol Ark and they said to buy a second Sol-Ark and parallel them.
I got the same reply only for my 12k unit. Expensive and overkill for a 2500 watt array. Currently my CC us outputtiing just 250w and the 12k is selling 170 watts from the DC side. Waiting to hear from S-A to see if it can be configured to sell all that array can produce.
 
Currently my CC us outputtiing just 250w and the 12k is selling 170 watts from the DC side.
The important number is the kWhs you are getting from each array to decide the best economic return. KW production is only a point in time. It may not represent the value of the energy going into your batteries. As others have already said it may not be worth changing. Optimum decisions should be based on data not assumptions.
 
I have been running an Eg4 100 amp charge controller on the same bank as my SolArk 12k for a few months now. I just set the voltages lower on the eg4. So as the batteries approach the end of the bulk phase the eg4 stops about .2 volt before the sol ark. I set the float voltage a little lower as well. It works perfectly.
Actually measure the voltage though. The solArk is off .1 volt, the EG4 is off .5 volt!
 
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