Adding on solar panels in series but no extra voltage?

[Alwynrm]

Hi all,

I've got 4 330w panels, that made 120v, which was only just enough to start to charge my all in one unit.

I therefore decided to add 2 more panels, which matched the stats of the first almost identically, except were half cells for better low light conditions. The wattage is also 355w per panel.

Given the above I assumed they would work, but I'm still only getting 120v overall and no more amps than before.

Why would this be? These can't be broken, can they, otherwise I'd be getting no power at all.

They are all connected in series.

Any ideas anyone?

Thanks!

Al

 

[Alwynrm]

Here are the new panels

 

[400bird]

Is that 120 volts open circuit? Or connected to the inverter?

I'd recommend checking open circuit on each panel. (and the series)
Also make sure the new panels have the same polarity on the MC4 connectors. If the new panels are reverse polarity that would cause an issue for sure.

 

[12VoltInstalls]

I've got 4 330w panels, that made 120v, which was only just enough to start to charge my all in one unit.

What All In One brand and model?

What region are you?

What batteries?
What state of charge?

What loads are being run?

No speculation with any reasonable suggestions are possible without more information.

 

[Alwynrm]

That's 120v at the inverter.

I'm running 4 X 12v 110ah lead acid batteries in series for 48v.

State of charge is batteries at 40%, so plenty of headroom. I'm in the UK.

I'm not running any big load....maybe pulling 100w at the moment.

The all in one unit is this one;

5.5KW Solar Inverter MPPT 100A 500VDC PV input 220VAC 48VDC 5.5KW WIFI Support | eBay

Find many great new & used options and get the best deals for 5.5KW Solar Inverter MPPT 100A 500VDC PV input 220VAC 48VDC 5.5KW WIFI Support at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

 

[12VoltInstalls]

State of charge is batteries at 40%, so plenty of headroom

That’s past a completely dead battery for lead acid btw

Your panels in series make lethal voltage. Literally. But you should use a meter on each one to confirm open circuit voltage and be extremely vigilant to not get shocked.

Check your PV cables for ohms.

From there I’m thinking you would likely need a systematic review of your settings to affirm that it is not limiting itself. Plus, sun angle and panel direction and the time of year you may be getting all there is available.

I might try two panels in series for fun. That may reveal something. Barring the SCC from being no good it just seems like a settings issue.

 

[MisterSandals]

That's 120v at the inverter.

Is that what you measure at the input terminals or what the inverter is showing on a screen?

 

[Alwynrm]

Is that what you measure at the input terminals or what the inverter is showing on a screen?

What the inverter shows on screen

 

[MisterSandals]

What the inverter shows on screen

Do you have a way to measure the voltage of the array disconnected from the inverter? With all in series, the connections should all be good to get 120V (or they would at least be warm/hot). You have to verify the array.