Below snap from the side of my inverter. The online spec sheet shows 13A MPPT limits so I'm assuming it'll start clipping there. But what is the 110A below, the max (Isc) it can handle from the panels? Sunsyk/Deye is only 17A so I'm not sure it's the same thing?

 

TL;DR I'm trying to figure out if the 14.39A STC Isc from my panels will be too much for this inverter.  

 

8 minutes ago, Zombie said:

Below snap from the side of my inverter. The online spec sheet shows 13A MPPT limits so I'm assuming it'll start clipping there. But what is the 110A below, the max (Isc) it can handle from the panels? Sunsyk/Deye is only 17A so I'm not sure it's the same thing?

 

TL;DR I'm trying to figure out if the 14.39A STC Isc from my panels will be too much for this inverter.  

 

I think it is this inverter that becomes unstable if any of the 2 MPPTs go over their maximum. 

The 110A is not Isc but the DC charging current to the batteries. The PV Imax is 13A as you indicated. That is from the panels for each MPPT. 

Oh, Is this inverter known for not being able to clip ?  I thought all inverters could clip current to some extent.

On 2023/05/29 at 1:59 PM, Scorp007 said:

I think it is this inverter that becomes unstable if any of the 2 MPPTs go over their maximum. 

The 110A is not Isc but the DC charging current to the batteries. The PV Imax is 13A as you indicated. That is from the panels for each MPPT. 

 

Edited May 30, 20233 yr by Zombie

5 minutes ago, Zombie said:

Oh, Is this inverter known for not being able to clip ?  I thought all inverters could clip current to some extent.

 

Yes we take it for granted that inverters clip. Some do but I know of 1 person that had problems expecting clipping to take place on any MPPT and the inverter behaved strange. 

My neighbour had one of those inverters when he started his solar journey.
After a couple of months one day he asked me to have a look what could be wrong as his Inverter was not charging the batteries nor providing power.
He has 12 X 545W panels that were strung 6S and 6S, i.e. one string for each MPPT.
I suspect that it is clipping the max amps but in his case I found that the max wattage seemed to have been exceeded. I think on that day he had around 3200W per string. I further suspect that the per MPPT max Wattage wasn't the cause but rather the total Wattage which would have been around 6400W for the two MPPT combined.
So I disconnected the one string and the Inverter returned to normal operation.
He duly went out and bought a second Inverter as he found he needed more than 5kW in any case.
His Installer came back to handle the installation and he now feeds one string into one MPPT on each Inverter respectively. Never had an issue since.
So in retrospect I am convinced that some circuitry inhibits the Inverter operation when the total Wattage is exceeded. 

Edited May 30, 20233 yr by zsde

Yes the 110 A max charging current means you can only get about 5.5 kW back through the DC-DC. It should of course cause one or both MPPTs to throttle back.

The luxpower inverter/website doesn't seem to log PV current. Can I just apply P=VI formula to the below values to work out the current?

20 hours ago, Zombie said:

Can I just apply P=VI formula to the below values to work out the current?

Yes. It's DC, no phase or power factor to worry about.

FYI. I emailed support and this is what they came back with. If the inverter starts acting up whilst under 3200W / 20A guess we have a leg to stand on.

Has anyone ran 5 x 2 550w strings on the sna5000 ? 

 

I'm getting conflicting information that it won't work due to the panels being >13a

1 hour ago, Jeppe said:

Has anyone ran 5 x 2 550w strings on the sna5000 ? 

 

I'm getting conflicting information that it won't work due to the panels being >13a

I don't have this inverter myself, but I'd go according to the info above from the manufacturer before taking the word of just anyone else.

With what they say, in principle, if your panels can have have an output above 13A, but below the Isc limit of 20A, then the current will be curtailed to just 13A drawn by the inverter.

Don't know your specs, but if your panel current is marginally over, like just over 13.5A, then don't worry, you'll see that only seldom at noon in summer on some days, or during cloud-effect short bursts. But if it's much higher, say closer to 16 or 17A, then re-think your choice of panel anyway. Even if it doesn't damage anything, it will probably be a waste of potential power that you'll never see most of the time.

As stated before,
My neighbour had a single one of these. He has 2 strings of 6 X 550W modules each.
Last summer his solar input shut down, i.e. the MPPT shut down. Not because of Amps as both strings are just at 13A, but seemingly because he exceeded the 6400W total of the MPPTs. Now it could have been that it was only one of the MPPTs where the wattage exceeded the 3200W as per the Inverter specs, although I rather suspect the total for both.
When I then disconnected the one string (random) the MPPT started accepting Solar again.
He then bought a second Inverter and is now feeding one string into each Inverter. Issue resolved.
So from this experience it seems that the SNA5000 will shut down the MPPT when the max wattage is exceeded irrespective of the Amps.
 

3 hours ago, Jeppe said:

Has anyone ran 5 x 2 550w strings on the sna5000 ? 

 

I'm getting conflicting information that it won't work due to the panels being >13a

I am running 2 strings, each consist of 5x 620W panels and so far all is good - however I do have 1 string per inverter (running 2 inverters in parallel).

My panels have a impp of 13.54A, isc is 14.25 and earlier today day I was getting just under 5400W from both strings combined.

 

Stick to within the specs and I doubt you will experience issues.

Edited August 23, 20233 yr by PsyCLown

3 hours ago, Jeppe said:

Has anyone ran 5 x 2 550w strings on the sna5000 ? 

 

I'm getting conflicting information that it won't work due to the panels being >13a

I'm running 2 strings of 5 x 575 into my SNA 5000. The panel's STC IMP spec is 13.5 amps but I've only seen it go as high as 12.5 (that doesn't mean it won't go higher). All is fine so far and I'm yet to see what happens (clipping) when the amps exceed 13.

Edited August 23, 20233 yr by Zombie

5 hours ago, Jeppe said:

Has anyone ran 5 x 2 550w strings on the sna5000 ? 

 

I'm getting conflicting information that it won't work due to the panels being >13a

You can run only 4 strings on the Sna 5000 unless you use external hardware to add the 5th string but running 5 x 2560wp= 12760wp way over the allowable wattage specified by manufacturer so no i don't think it would be wise.

2 hours ago, TaliaB said:

You can run only 4 strings on the Sna 5000 unless you use external hardware to add the 5th string but running 5 x 2560wp= 12760wp way over the allowable wattage specified by manufacturer so no i don't think it would be wise.

@Jeppesorry i misinterpreted your 5 x 2 550w incorrectly you meant 5s/mppt then yes you can as the total would be 5500w total within spec of the inverter MPPTs.