Sol-Ark 15K AC coupled setup to reduce grid supplied power

[DIYrich]

That would cycle battery and switch SolArk between 100% and off.
Can you get it to operate smoothly with Rule-21 frequency-watts?

The only time you need to throttle AC PV production is when the grid is down. For those times, if the batteries are at 80%, I'm ok with turning off AC PV for a while.

 

[BenW]

I have SE7600 also grid tie with 9.8kw PV. I am interested in installing a Sol Ark, so I can add more PV panels via DC. What is grid code 14 on the solarEdge?

It is: US 240V No-Neutral. If you have a neutral there is a grid code listed for that, as well.

 

[JeepHammer]

I don't want to side track the thread...

Sol-Arc 15 has both AC and DC coupling capabilities (FINALLY!) and with a few installs under my belt I'm still learning g what it's capable of.

You can do the 'Up' side of both AC and DC coupling if you can get the configuration correct...
And so far the Sol-Arc people have been VERY cooperative in working with us self-taight hillbilly installers/operators.

Our biggest 'Problem' has been the vocabulary, out here in the brush we simply don't know the correct terms so getting the proper question formulated to get what we want sometimes goes on longer than it should (entirely our fault).

The EG 18k doesn't have a 'Ramp Down' mode which causes some issues, the Sol-Ark 15k DOES have a ramp down for battery charging that stops a lot of minor problems. The trick is getting it activated...

The 15k unit it's self does managing the 'ramp up' when production comes on line, it has 'soft start' built in, no 'flutter', no surge/drop, no 'morning effect' issues at all.

If you really want to get into it, order the engineer's technical manual for the 15k.
(Have an electrical engineer's dictionary handy...)
Everything you ever wanted to know (and a lot of things you never heard of) are in that manual.

 

[byteharmony]

The only time you need to throttle AC PV production is when the grid is down. For those times, if the batteries are at 80%, I'm ok with turning off AC PV for a while.

What if the battery voltage was monitored by a simple device like this:


When we hit X% battery the relay trips off to disconnect AC coupled solar on the load side of the sol ark.

Would be ideal to have a voltage detection device with a programmable delay on the relay to avoid the grid tie going on and off too often when off grid.

 

[Ampster]

What if the battery voltage was monitored by a simple device like this:

I am not sure what problem is being solved with this device? Shutting off the AC coupled solar when the grid is down is done automatically by the SolArk, either through the gen port relay or by frequency shift.
When the grid is up there is no need to shut off the AC coupled solar.

 

[byteharmony]

I am not sure what problem is being solved with this device? Shutting off the AC coupled solar when the grid is down is done automatically by the SolArk, either through the gen port relay or by frequency shift.
When the grid is up there is no need to shut off the AC coupled solar.

I talked with sol-ark support about this and it's a little more complicated than that. If the battery is not charged and the grid is down

If the solar is on the gen port it will stay connected to run the battery charger - this is where you may want to cut power to a dumb / no frequency shifting inverter when the battery is charged to avoid power being generated that isn't used. You also have to make sure your load legs are balanced, the sol ark charger and solar power created are both 240v systems.

If the solar is on the load port then it will stay connected - this is also where you may want to cut power to a dumb / no frequency shifting inverter when the battery is charged to avoid power being generated that isn't used.

 

[Ampster]

to avoid power being generated that isn't used.

How is that a problem, unless you are talking about generator power which consumes fuel?
EDIT: It is a problem if the power being generated is via AC coupling and the power being generated is capable of burning up the hybrid inverter which is providing the sync signal because the GT inverter cannot shut down quickly enough.

 

[RCinFLA]

I talked with sol-ark support about this and it's a little more complicated than that. If the battery is not charged and the grid is down

If the solar is on the gen port it will stay connected to run the battery charger - this is where you may want to cut power to a dumb / no frequency shifting inverter when the battery is charged to avoid power being generated that isn't used. You also have to make sure your load legs are balanced, the sol ark charger and solar power created are both 240v systems.

If the solar is on the load port then it will stay connected - this is also where you may want to cut power to a dumb / no frequency shifting inverter when the battery is charged to avoid power being generated that isn't used.

Simple answer on Sol-Ark using generator port for AC coupling is if it gets into trouble with no place to put the PV power it just 'pulls the plug' to PV GT inverter by opening gen input relay.

Toughest situation is when PV is generating a lot of power and either the grid drops out, or if off grid, a large house load is turned off. All of sudden there is too much PV power with no place to go other than battery. Freq shifting is not fast enough to help in this situation.

If excess PV power exceeds inverter maximum battery charging power capability, or battery SoC is such that inverter maximum allowed DC input voltage is about to be exceeded due to heavy charging current back push, it will dump the AC coupling of PV GT inverter by opening gen port relay to save itself from damage.

If you inject PV GT inverter directly into ACout of inverter, in this situation, the only thing it can do is shut down the SolArk inverter and drop all AC output to save itself from damage.

 

[BlueMarblePA]

Simple answer on Sol-Ark using generator port for AC coupling is if it gets into trouble with no place to put the PV power it just 'pulls the plug' to PV GT inverter by opening gen input relay.

Toughest situation is when PV is generating a lot of power and either the grid drops out, or if off grid, a large house load is turned off. All of sudden there is too much PV power with no place to go other than battery. Freq shifting is not fast enough to help in this situation.

If excess PV power exceeds inverter maximum battery charging power capability, or battery SoC is such that inverter maximum allowed DC input voltage is about to be exceeded due to heavy charging current back push, it will dump the AC coupling of PV GT inverter by opening gen port relay to save itself from damage.

If you inject PV GT inverter directly into ACout of inverter, in this situation, the only thing it can do is shut down the SolArk inverter and drop all AC output to save itself from damage.

I don't want to hijack the thread, but I have a similar question

I have CL320 (aka 400 amp service) with 2 x 200 amp main electrical panels. I have Solaredge 7600 backfeed 40amp breaker PV AC into one panel - noncritical - and it has more open breaker positions. I am planning to create a "critical loads" 200amp panel with the other main electrical panel, and use a Solark 15k to feed that panel. I plan to bring in another 6K PV DC to the Solark15k.

If I don't feed in the Solaredge AC inverter input into the gen input of the Solark, and if I leave it in a separate electrical panel, will this be a problem? If the grid power goes down, I will lose all Solaredge 7.6k (9.8kw DC PV), but I will still have the Solark 15k (6K PV DC). I do not have any batteries, and so DC PV will simply feed house loads but without batteries there may be some problems keeping up of course. I plan to migrate all the PV (both AC coupled and DC) eventually, but I want to be sure that everything is working before doing this, and thus there will be a few weeks where it will be separate. In addition, I plan to get batteries in stages.

 

[DIYrich]

I don't want to hijack the thread, but I have a similar question

I have CL320 (aka 400 amp service) with 2 x 200 amp main electrical panels. I have Solaredge 7600 backfeed 40amp breaker PV AC into one panel - noncritical - and it has more open breaker positions. I am planning to create a "critical loads" 200amp panel with the other main electrical panel, and use a Solark 15k to feed that panel. I plan to bring in another 6K PV DC to the Solark15k.

If I don't feed in the Solaredge AC inverter input into the gen input of the Solark, and if I leave it in a separate electrical panel, will this be a problem? If the grid power goes down, I will lose all Solaredge 7.6k (9.8kw DC PV), but I will still have the Solark 15k (6K PV DC). I do not have any batteries, and so DC PV will simply feed house loads but without batteries there may be some problems keeping up of course. I plan to migrate all the PV (both AC coupled and DC) eventually, but I want to be sure that everything is working before doing this, and thus there will be a few weeks where it will be separate. In addition, I plan to get batteries in stages.

If the Solaredge is between the Grid and the Grid Input of the Sol-Ark, it is ok.

 

[BlueMarblePA]

If the Solaredge is between the Grid and the Grid Input of the Sol-Ark, it is ok.

Yes. Since it will be on grid side and not on solark side, it makes sense that it would just shut off

 

[byteharmony]

sing generator port for AC coupling is if it gets into trouble with no place to put the PV power it just 'pulls the plug' to PV GT inverter by opening gen input relay.

Toughest situation is when PV is generating

If the Solaredge is between the Grid and the Grid Input of the Sol-Ark, it is ok.

Okay, but also not giving you any power when the grid is down, which is the topic of this thread.

If it were on the gen input then it could charge the battery and power the loads when the grid is down. It just needs protection in the event the battery is full.

 

[RCinFLA]

Okay, but also not giving you any power when the grid is down, which is the topic of this thread.

Where do you get that interpretation?

When grid drops, the SolArk opens grid input pass-through relay and becomes AC phase master. It provides a surrogate grid to the PV GT inverter. Gen input pass-through relay stays closed throughout the switch over from grid to inverter mastering process.

When grid drops there is a short period (less than half AC cycle) overload on SolArk inverter which triggers the grid input pass-through relay release. There is a small glitch that most device loads ride through, including PV GT inverter. If the glitch does cause PV GT inverter to shut down it will immediately resync and reconnect to SolArk in the normal amount of time it takes to synchronize and connect to grid.

 

[BlueMarblePA]

Where do you get that interpretation?

When grid drops, the SolArk opens grid input pass-through relay and becomes AC phase master. It provides a surrogate grid to the PV GT inverter. Gen input pass-through relay stays closed throughout the switch over from grid to inverter mastering process.

When grid drops there is a short period (less than half AC cycle) overload on SolArk inverter which triggers the grid input pass-through relay release. There is a small glitch that most device loads ride through, including PV GT inverter. If the glitch does cause PV GT inverter to shut down it will immediately resync and reconnect to SolArk in the normal amount of time it takes to synchronize and connect to grid.

I think DIYRich and Byteharmony were just referring to my specific situation where the 200amp does not come out of the load output from the Solark 15k. Instead, I have a separate 200 amp panel which directly connects to the grid CL320 - 400 amp meter and has the Solaredge backfed into that panel.