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jimbo1

Hello, i am new to forum just need a bit of advice, installation of a 3600tl sma inverter going in to lockout overvoltage first thing in mornings been ok up until nw 3 months old, panels are 250 x16 on single string is this the problem should it be 2 string has shown up to 630v dc max at moment but is in lockout mode any help??
 
The max DC voltage is 750V for the 3600tl, are you sure it is not the AC that is going overvoltage?

This is a common install problem if the AC cable is too small that connects the inverter to the supply, even more so if it is a long run.
 
The ac cable is 2.5mm and 2mtrs from supply ac showing between 244-249v sma stated that this inverter will only accept 550v from 16 panels although no ane has factored in 10% for cold panels am i right in saying it is overheating from 1 string setup.
 
I don't have the spec sheet in front of me but I would have thought the upper limit on the MPPT would be less than 750v.

The voltage will be quite high on the last few mornings as we have had lots of sunshine and very cool temperatures - perfect conditions for high voltages.

What error message are you getting exactly? Are you sure that the inverter is set up for G83?
 
sma checked serial number and say it is setup for g83, inverter states this also panels are ja 250 can it be that dc input needs to be raised/adjusted from initial commisioning
 
If its 3months old then its probably a SB3600TL-20 which has a 550VDC max input voltage. The SB-3600TL-21 released turn of the year has a higher input voltage.
Isolate the DC (dc isolators or the ESS handle) until it can be split into 2 separate strings. Overvoltage can damage the inverter, and over voltage isn't covered by warranty!

You need to get it put into 2 strings!

Ken
 
Hello, i am new to forum just need a bit of advice, installation of a 3600tl sma inverter going in to lockout overvoltage first thing in mornings been ok up until nw 3 months old, panels are 250 x16 on single string is this the problem should it be 2 string has shown up to 630v dc max at moment but is in lockout mode any help??
SMA 3600TL-21 or -20?

If it's a 21 then it's the higher voltage model then it should be fine as even at -10deg the Voc should be around 698V vs 750Voc maximum on the inverter.

I suspect thought hat it might be an 3600TL-20, which has 550Voc max and 440V max MPPT voltage, and you've been just skirting inside those limits until it's got a bit colder (the voltage is reduced at lower light levels and in higher temperatures, so the combination of the 2 might have just kept you inside the limits).

I did find out recently that some of the chinese panels are coming with +/- 10% variation on the voltage, which could also explain this.

Either way, it looks like the string is going to have to be split as one way or another it's going over voltage whatever the calcs say.
 
very helpfull ken , i thought i was getting there with 1or 2 string configuration but will it still work in 2 strings if you have 16 panels with no shading ssw 45 deg roof,
 
installer error I would have thought. Simple enough to use SMA sunny design to make sure the system is designed correctly
 
2 strings will work fine. Min start voltage is 150vdc, mppt range 175v - 440vdc so your 630/2 = 315vdc which is right in the middle of the working range.

I'd say installer error - yes the model did change and extend the dc input range, but why install a twin tracker inverter and only use one input? If you wanted to do a single input, use something like a Fronius 3.6TL.

Ken
 
will this inverter log all errors and if service engineer from sma turns up will he say if warranty is void if error code 34 has been consistently happening for a few months and poss bring on other faults
 
imo the installation company should come out and change the string arrangement or swap for a SMA 21 version if they want to connect in a single string.
 
The installer should come out and change the string configuration - no need to swap the inverter.
Yes the inverter will log all errors, but the over voltage is slight - as soon as the inverter starts connects to the grid and starts generating the dc voltage will drop to about 500v which is in range.
If the voltage had been higher it would have hopefully blown the varistors on the input stage to protect the rest of the inverter.
The fact you saw the warning error messages is good - its when the voltage is higher and you don't see any warning message - thats when you have a problem!

Ken
 

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