Am i buying a decent hybrid and is it legitimate advice needed,

[heather-]

Oh, 13.24A and 9.94A
Don't want them in series.

Inverter has 2x MPPT inputs.

Trina 6 x 41.7Vmp = 240V or so (decreases a bit when hot),

Longi 5 x 31.73V = 150V or so

Inverter 150V minimum MPPT.

Would like at least one more Longi.
How about 5 longi + 1 Trina in series for one MPPT input, 5 Trina for other MPPT input?
Both of those will be about 190V to 200V.
Nah, probably not better than all in series. for power.

But Voc adds up to 487.5V
I think this may exceed 500V in the cold!
Don't run all 11 in series!

Try to get at least one more Longi

I'm told the preferred degree angel for winter months is about 50 degrees or so up here in the UK, to achieve the highest possible amps, my panels will always be set at only 7 degree tilt angle , would this make a difference ?, as in your estimate possibly achieving more than or close to 500 v in the cold,.

Is it is possible if I kept the panels at a 7 degree tilt angle in the winter , thIs would prevent them from not going anywhere near the 500v max

 

[Hedges]

Angle doesn't matter to Voc. Just temperature and temperature coefficient and Voc spec of panels & quantity.

Angle matters for current and watts.

500V spec is for one MPPT input, and the panels connected to that one input.
Other MPPT input also has 500V spec, and consider only the panels connected to it.

The math says we could exceed 500V. The math comes way to close even before applying temperature coefficient.
You need a different string configuration.

One guy blew three Midnight Classic. They replaced the first under warranty. They replaced the second under warranty. He was upset when they didn't replace the 3rd. I connected a cheap import hybrid with higher voltage rating and said, "See! These don't fail!"

 

[heather-]

Angle doesn't matter to Voc. Just temperature and temperature coefficient and Voc spec of panels & quantity.

Angle matters for current and watts.

500V spec is for one MPPT input, and the panels connected to that one input.
Other MPPT input also has 500V spec, and consider only the panels connected to it.

The math says we could exceed 500V. The math comes way to close even before applying temperature coefficient.
You need a different string configuration.

One guy blew three Midnight Classic. They replaced the first under warranty. They replaced the second under warranty. He was upset when they didn't replace the 3rd. I connected a cheap import hybrid with higher voltage rating and said, "See! These don't

Hi thanks, , im not going to connect the panels in series of 11 panels, so I'm keeping 5 on one string and six on the other,. Am I right in thinking each mppt can take 500 voc each, ?

Sorry I'm still confused ?

However I think I'm going to take your suggestion and put 5 longi and one Trina on one string, and 5 trina on the other, as I'm not so sure this unit can take 500 voc on each mppt,

I'm thinking if it could this would be clearly illustrated on the inverter spec picture you saw in previous post.

 

[heather-]

Hi again @Hedges

Ok I just did what you recommended

I've attached 5 longi panels and one Trina on one mppt and 5 trina on the other, please note that this reading is without any load going through the inverter,

Ie the ac is switched of at the moment,.and the inverter is showing off as ac is not switched on at present.

I'll do a second reading later under load after I hear back of you.

From the reading would you say this is more like a Voc reading ? Times is 6 am early morning quite cold.

Two pictures attached one showing mppt voltage open circuit voltage, which i assume is the Voc ?

And the other showing you the inverter is of, ie no load going out.

It's not making a difference yesterday on 6 Trina I had 275 v and on the 5 long I had 175 v.

So the result is the same either way 450 volts @Hedges

 

[heather-]

Just another thought @Hedges chuckles

Hope your doing ok my besty mate here

I've noticed that as soon as the solar power is under load the voc voltage goes right down.

So my thought is, if my inverter is under load as soon as it switches on automatically of a morning , every morning that voc voltage should never go above for 450v and would be more like 400v.

Of course there will be a period of no Amps untill the sun rises, I guess in that period there would be a higher voc voltage untill the solar starts producing.

I guess I would have to see in a few months

Would that be a correct assumption

 

[Hedges]

Hi thanks, , im not going to connect the panels in series of 11 panels, so I'm keeping 5 on one string and six on the other,. Am I right in thinking each mppt can take 500 voc each, ?

Sorry I'm still confused ?

MPPT "A" can take up to 500V.
MPPT "B" can take up to 500V.

However I think I'm going to take your suggestion and put 5 longi and one Trina on one string, and 5 trina on the other, as I'm not so sure this unit can take 500 voc on each mppt,

Ok I just did what you recommended

I've attached 5 longi panels and one Trina on one mppt and 5 trina on the other,

6 Trina is fine for one MPPT input. That's 300Voc. 246Vmp

5 Longi is not quite enough for one MPPT input. That's 188Voc, 158 Vmp.
Inverter minimum 150V MPPT operation, so it will work with panel at room temperature but as panel warms in the sun the voltage will drop maybe 10%, to around 140Vmp. The inverter won't go below 150V so power output o panels well be much lower than it should be.

Oh, 5 Longi + one Trina, as I suggested might work. Yes, that should get the voltage high enough.
It will limit current to Trina's current so you lose about 1/4 of they wattage Longi should have produced, but that is better than losing most of it at minimum MPPT voltage, and better than killing the inverter with 11 PV panel over-voltage in cold weather.

Should work for now, try to find a panel closer to Longi's 13A.

If string was shorted, it might push 14A through Trina and damage the diode. Which could then melt/crack the panel (even though 14A is below 20A fuse rating.) Make sure this Trina panel won't get shaded when Longi is in full sun, which would also put excess current through it.

It's not making a difference yesterday on 6 Trina I had 275 v and on the 5 long I had 175 v.

So the result is the same either way 450 volts

Don't add the voltage 275V and 175V together.
Compare 275V to 500V max.
Compare 175V to 500V max.

Add the wattage together.

 

[heather-]

MPPT "A" can take up to 500V.
MPPT "B" can take up to 500V.





6 Trina is fine for one MPPT input. That's 300Voc. 246Vmp

5 Longi is not quite enough for one MPPT input. That's 188Voc, 158 Vmp.
Inverter minimum 150V MPPT operation, so it will work with panel at room temperature but as panel warms in the sun the voltage will drop maybe 10%, to around 140Vmp. The inverter won't go below 150V so power output o panels well be much lower than it should be.

Oh, 5 Longi + one Trina, as I suggested might work. Yes, that should get the voltage high enough.
It will limit current to Trina's current so you lose about 1/4 of they wattage Longi should have produced, but that is better than losing most of it at minimum MPPT voltage, and better than killing the inverter with 11 PV panel over-voltage in cold weather.

Should work for now, try to find a panel closer to Longi's 13A.

If string was shorted, it might push 14A through Trina and damage the diode. Which could then melt/crack the panel (even though 14A is below 20A fuse rating.) Make sure this Trina panel won't get shaded when Longi is in full sun, which would also put excess current through it.




Don't add the voltage 275V and 175V together.
Compare 275V to 500V max.
Compare 175V to 500V max.

Add the wattage together.

Thanks I appreciate but Its not syncing in with my new sunny head chuckles . I've had clarification of sunsynk through there app via live chat,

A sunsynk rep said both mppt controller have a rated power of 370 volts each, and ideally he said I should try to stay below that, he did say I could have 370 volts going into each mppt at the same time and I would be safe, from two separate strings of panels,

He then said this,,, The PV input voltage 500V max refers to the maximum open circuit voltage (Voc) the entire inverter can handle from the solar panels.





This bit I don't understand. As I didn't get clarity if that was for one mppt or both ?

How can the open circuit voltage for the whole inverter be 500 v, when he's recommended I could have 2 x 370 rated volts going in at one time ?.

Because surely if your driving that much voltage in then your open circuit voltage is going to be higher than 2 x 370 volts ?.

Is it the case that one mppt must not exceed 500 v, or is it, do you add the Voc together from both mppt controllers,

So my reading earlier was 230 v open circuit on one mppt and 230 v on the other mppt, does that mean 460 v open circuit is passing through ?. Or only 230 v ?

 

[Hedges]

Each MPPT is allowed up to 500V open circuit, no current being drawn.
At maximum power of panels, voltage will be about 80% as high, 400V. Fairly close to optimum 370V of MPPT operation.

Only 230V. The two MPPT inputs are separate. The outputs are tied in parallel. Just like anyone with two SCC both charging their battery.

 

[heather-]

Each MPPT is allowed up to 500V open circuit, no current being drawn.
At maximum power of panels, voltage will be about 80% as high, 400V. Fairly close to optimum 370V of MPPT operation.

Only 230V. The two MPPT inputs are separate. The outputs are tied in parallel. Just like anyone with two SCC both charging their batteryciol

Cool Ty I thought as much, chuckles, it's got me in a pickle lately, I did achieve 3800 watts under load today, so a fast improvement, which I'm really happy about, and also I was achieving 1.4 kilowatts in cloudy weather, which is a bonus for the charging of my EV.

I've been trying to understand this.

On the the picture am i Correct in thinking that this unit can handle temperatures of 60 c 140 f

The manual says it will start to derate at 45 c ? 113 f

What does that mean derate ?

The picture illustrates the highest temps my inverter has gone to in three weeks of use, would it be wise to get a fan

 

[Quattrohead]

Just another thought @Hedges chuckles

Hope your doing ok my besty mate here

I've noticed that as soon as the solar power is under load the voc voltage goes right down.

So my thought is, if my inverter is under load as soon as it switches on automatically of a morning , every morning that voc voltage should never go above for 450v and would be more like 400v.

Of course there will be a period of no Amps untill the sun rises, I guess in that period there would be a higher voc voltage untill the solar starts producing.

I guess I would have to see in a few months

Would that be a correct assumption

This is a correct assumption UNTIL either your battery is fully charged and/or you have no AC load, then the mppt will stop drawing power and the voltage will float up to the full VOC. This is when the magic smoke starts looking for an escape route.

 

[heather-]

This is a correct assumption UNTIL either your battery is fully charged and/or you have no AC load, then the mppt will stop drawing power and the voltage will float up to the full VOC. This is when the magic smoke starts looking for an escape route.

Hi quatro head

I've been tying to get my head around this for a while now, I'm wondering the best way round it.

I understand that the inverter dumps any unused electric from the solar,.but I'm not fully understanding how that works.

I guess if always feeding into the grid I wouldn't have to worry.

But I have to wait another couple of months to get it
at the moment before I can start feeding access into the grid, even tho currently it is grid tied, I have the zero export on.


I wonder what I can do to limit the amount that gets dumped ?. Any suggestion would be appreciated Ty

 

[heather-]

from my research it seems i can dump access solar into water heater, does anyone know the least cost effective way of doing this and the process, and is there more than one way of doing it ty

i do have an unused hot water heater at home, which i could use. but im clueless as to how to set it up at the moment

 

[Quattrohead]

I understand that the inverter dumps any unused electric from the solar,.but I'm not fully understanding how that works.

It does not dump anything anywhere, it just does not draw from the panels if it's got no where to push the power.

 

[heather-]

It does not dump anything anywhere, it just does not draw from the panels if it's got no where to push the power.

Thanks ,

Do you know anything about theese settings, picture included.

I'm thinking if I set the aux load to 500 watts does that mean it won't draw more than 500 watts from the solar. Picture attached

Also you mentioned the invisible smoke looks for a place to escape, is this to do with un-used electricity not being used from the panels ?.