Growatt showing 0 Amps and very low watts from PV

[AHUSAIN]

Hello,

I just installed a 1,000 watt array with 2 series strings of 500 W each paralleled together. The panels are brand new (just released 100 W mono from Grape Solar). I have attached this array to a brand new Growatt 3000TL SPF LVM. The array voltage looks normal. However, the Growatt is showing only between 15 to 35 W being generated by the array. It is also showing 0 Amps for the entire panel array.

It is about 10 AM and there is still a lot of shade from the trees but why on earth would it say 0 Amps while the battery charger indicator LED is clearly blinking? And is it reasonable to expect such a low wattage for this 1,000 W array? I have another 2 strings left to add.

I did confirm that each string independently is showing a correct voltage reading in the Growatt panel. I also left a small fan constantly running as a load to test out the system.

This is my first system. Any help would be greatly appreciated.

 

[snoobler]

I'd wait to see what happens when they get hit with full sun.

Growatts sometimes require a "reset" where the are completely powered off...

Disconnect from Solar
Disconnect from AC input
Disconnect from battery

Reconnect in reverse order.

 

[AHUSAIN]

I'd wait to see what happens when they get hit with full sun.

Growatts sometimes require a "reset" where the are completely powered off...

Disconnect from Solar
Disconnect from AC input
Disconnect from battery

Reconnect in reverse order.

Thank you. It actually did start reporting amps when the sunlight hit directly. It is still far below what I hoped but at least alive.

 

[GXMnow]

At "solar noon" with the sun directly over the panels, your 1,000 watt array will likely be able to make about 800 watts depending on panel angle, weather, and panel temperature. On a 12 volt system, that would be about 56 amps to the batteries, 28 amps at 24 volts, and just 14 amps on 48 volts. And that is only if the batteries are in the middle of the charge curve and in bulk charge mode. If your battery bank is near full, the system will not pull much current from the solar panels as it has no place to send the power. When you are at your solar noon (about 1:30 pm where I live) turn on some heavy loads on the system to pull the batteries down, and then see what your solar array voltage and current is. Your array is a 5S2P of 100 watt panels, but without the VMP and IMP specs, it is only a guess as to where they should be running. A basic Renogy 100 watt panel has these specs. IMP 5.38 amps, and VMP 18.6 volts. If yours are much different, you will have to do the math, but here is what I get using these panels as an example. With 5S2P the voltage is 5 times or 93 volts, and the current is double 10.76 amps for the full 1,000 watts. But in real world temperature, and not ideal sun, the panels might be closer to 80 volts at 10 amps. If the voltage is higher, then the charging may be going into the absorb or float mode and the current will be much less. If you have a DC clamp meter, you can check to make sure both strings are putting out half the power. on bad connection in a series string will drop out half of the array. So if your current is close to 5 amps even under load in full sun, that is where I would start looking. Keep in mind, even a small shadow on one panel can basically cut off one whole string also.

 

[AHUSAIN]

At "solar noon" with the sun directly over the panels, your 1,000 watt array will likely be able to make about 800 watts depending on panel angle, weather, and panel temperature. On a 12 volt system, that would be about 56 amps to the batteries, 28 amps at 24 volts, and just 14 amps on 48 volts. And that is only if the batteries are in the middle of the charge curve and in bulk charge mode. If your battery bank is near full, the system will not pull much current from the solar panels as it has no place to send the power. When you are at your solar noon (about 1:30 pm where I live) turn on some heavy loads on the system to pull the batteries down, and then see what your solar array voltage and current is. Your array is a 5S2P of 100 watt panels, but without the VMP and IMP specs, it is only a guess as to where they should be running. A basic Renogy 100 watt panel has these specs. IMP 5.38 amps, and VMP 18.6 volts. If yours are much different, you will have to do the math, but here is what I get using these panels as an example. With 5S2P the voltage is 5 times or 93 volts, and the current is double 10.76 amps for the full 1,000 watts. But in real world temperature, and not ideal sun, the panels might be closer to 80 volts at 10 amps. If the voltage is higher, then the charging may be going into the absorb or float mode and the current will be much less. If you have a DC clamp meter, you can check to make sure both strings are putting out half the power. on bad connection in a series string will drop out half of the array. So if your current is close to 5 amps even under load in full sun, that is where I would start looking. Keep in mind, even a small shadow on one panel can basically cut off one whole string also.

Well that helps! Thanks a lot for all that detail. I suspected it was drawing low amps because my batteries were nearly full but I couldn't confirm that from the manual.

 

[snoobler]

Well that helps! Thanks a lot for all that detail. I suspected it was drawing low amps because my batteries were nearly full but I couldn't confirm that from the manual.

A great way to get around that for testing purposes is to apply loads greater than the power of your array.

 

[Bleedingblue]

Hello,

I just installed a 1,000 watt array with 2 series strings of 500 W each paralleled together. The panels are brand new (just released 100 W mono from Grape Solar). I have attached this array to a brand new Growatt 3000TL SPF LVM. The array voltage looks normal. However, the Growatt is showing only between 15 to 35 W being generated by the array. It is also showing 0 Amps for the entire panel array.

It is about 10 AM and there is still a lot of shade from the trees but why on earth would it say 0 Amps while the battery charger indicator LED is clearly blinking? And is it reasonable to expect such a low wattage for this 1,000 W array? I have another 2 strings left to add.

I did confirm that each string independently is showing a correct voltage reading in the Growatt panel. I also left a small fan constantly running as a load to test out the system.

This is my first system. Any help would be greatly appreciated.

Not enough sunlight on the panels to generate enough power to make the Growatt start working

 

[stienman]

Well that helps! Thanks a lot for all that detail. I suspected it was drawing low amps because my batteries were nearly full but I couldn't confirm that from the manual.

Whether that happens or not depends on your battery settings. If you choose the lithium user setting, it shuts off charging completely when it determines the batteries are full, and doesn't resume charging until the battery voltage drops to a certain point. If you choose the lead acid user setting it will continue charging at a lower rate.

 

[wtrey613]

We just hooked our panels up to our Growatt 5000Es, and the growatt was not registering they were there. We have 8 Panels 300w (45V 8amps) hooked up in 2S4P (90V 32Amps). Our battery is 48V. so we figured the sunlight was too little or our panels our wired incorrectly. But shouldn't the symbol (PV to Growatt) show up on the LED screen? showing there is a connection?? that wasnt even showing up.

 

[stienman]

shouldn't the symbol (PV to Growatt) show up on the LED screen? showing there is a connection?? that wasnt even showing up.

Only if the panels are providing enough power to give the minimum voltage for the growatt mppt charger.

 

[Bud Martin]

We just hooked our panels up to our Growatt 5000Es, and the growatt was not registering they were there. We have 8 Panels 300w (45V 8amps) hooked up in 2S4P (90V 32Amps). Our battery is 48V. so we figured the sunlight was too little or our panels our wired incorrectly. But shouldn't the symbol (PV to Growatt) show up on the LED screen? showing there is a connection?? that wasnt even showing up.

Do you have Volt meter to check and see if you do have DCV present at the PV input of the SCC?

 

[wtrey613]

Only if the panels are providing enough power to give the minimum voltage for the growatt mppt charger.

I feel like an idiot, but I just checked my specs. our min VDC for array is 120 Volts. and our max is 450 V-DC.
So I will be putting them in series!
With min VDC, is that VMP or VOC of the panel array?

 

[stienman]

I feel like an idiot, but I just checked my specs. our min VDC for array is 120 Volts. and our max is 450 V-DC.
So I will be putting them in series!
With min VDC, is that VMP or VOC of the panel array?

The VMP should be higher than the minimum VDC, otherwise the charge controller will not be able to use the panels at their most efficient. The VMP should fall somewhere between the min and max VDC, and the charge controller probably has a smaller range where it prefers the VMP to fall. For the range you've given, I'd suspect the charge controller would like to see the VMP close to 370VDC.

The VOC MUST be under the max VDC.