SB3600TL readings sound right?

[Gavin A]

Sundown didnt post the first post ?? and he quite clearly said he has 10 panels facing SE in his last one I replied to.

yes, but he did post HIS first post on the thread.

in the same situation as op.ie sb 3600tl 10 panels south west, 5 panels south east with chimney panels suntolight [ german] 2.5 watt.
we could check together . i live 30 miles north of london

 

[Glen Powell]

SMA minimum startup voltage 150v
Power one minimum start UP voltage 100v

The fact that the AC side is higher would make it more efficient

 

[Glen Powell]

And my post saying "sorry unless you replied earlier" meaning I did not go through all the posts again

 

[Glen Powell]

Before you say

voltage/temperature

yes I know voltage is not as important as current but with a small amount of panels it makes a massive difference

 

[Gavin A]

And my post saying "sorry unless you replied earlier" meaning I did not go through all the posts again

so you thought you'd just jump straight in and tell the guy his system was wrong. Interesting approach.

 

[provr6]

SMA minimum startup voltage 150v
Power one minimum start UP voltage 100v

The fact that the AC side is higher would make it more efficient

Do those min'm start up voltages matter, as surely both me and sundown easily exceed those?

 

[Glen Powell]

well if he has 5 panels SE facing then yes I would still jump in and say it is not really as good as it should be max ppt voltage on sanyo hit250 = about 175v (maximum)

 

[provr6]

well if he has 5 panels SE facing then yes I would still jump in and say it is not really as good as it should be max ppt voltage on sanyo hit250 = about 175v (maximum)

I see, but am I right in saying that the 10 panels on sundown's other roof would help meet the start up voltage? My installer said the start up voltage is based on the combined 2 roofs?

 

[Glen Powell]

I am sorry for being too eager to try and help were help is not really neaded, I dont really like SMA and was trying to get you all to change inverters for one I was trying to sell you or give others the opportunity to sell you.

Minimum voltage has no bearing on this matter
Miniimum ampage or maximum ampage are useless
Conversion factors have no relevence at all
Coil sizes and losses are just buzzwords
Transistors have no place in an inverter

I am sure the installer installed exactly what was needed for you and those bringing my posts into question

 

[Glen Powell]

I see, but am I right in saying that the 10 panels on sundown's other roof would help meet the start up voltage? My installer said the start up voltage is based on the combined 2 roofs?

2 mppt = 10 on one and 5 on the other

 

[Glen Powell]

.hmmm really

 

[provr6]

You are obviously more knowledgeable than me and I wasn't criticising your advice. I was just stating advice received from my installer and putting it out there for those in the know to verify or rebuke.

On the contrary, I am grateful for your comments and all considered comments are welcome, even if it's not good news.

 

[Gavin A]

I see, but am I right in saying that the 10 panels on sundown's other roof would help meet the start up voltage? My installer said the start up voltage is based on the combined 2 roofs?

tbf to your installer, they were right about this when they'd first installed your system as they'd wired both arrays in series to the one MPPT input.

Now it's wired to the 2 separate MPPT inputs that's not the case, the voltage on each array is independent of the other.

 

[Glen Powell]

The basics of it is this

I am the technical director of 2 companies of which 1 deployed 500 installs in February, the inverter choice for your install would not have entered my design teams heads, if the designer of your system used any design software it would have probably spat it out and said no way or it would base it on the strong MPPT and give you a very poor efficiency rating.

In one of the sticky topics I have put a spread sheet up to help measure efficiency but you do need an irradiance meter (original thread goodwilld) on page 69 of the thread.

Be fully aware this is not my investment, this is really not my concern, but if your quarterly return is less than others you will not be happy. this is why I have given links to SMA software and their phone number. you can say you are going to install a system in this way and is it acceptable, take notes, get names, etc.

I will not loose 1 snippet of sleep tonight over this, if i am right or wrong is irrelevent which is why I say speak to the manufacturers.

 

[Glen Powell]

tbf to your installer, they were right about this when they'd first installed your system as they'd wired both arrays in series to the one MPPT input.

Now it's wired to the 2 separate MPPT inputs that's not the case, the voltage on each array is independent of the other.

Doesn't matter the underperformance of one will pull the other down, 101 solar design, the weak array will create resistance for the strong array if in series, if in parallel maybe a chance but not much as there is still an adverse effect.