Hello, its 22h56 and my panels are showing 7W of power (String 1 = 2W and String = 5W). Its a overcast and rainy night, no Moon (in case that has an effect). Is it normal for the Panels to produce single digit Watts at night? If not, what is the possible cause/fix? Many thanks in advance!

It's normal for most Inverter to show a few Wats , don't think it's the panels generating any Wats but the inverter showing Wats that's not really there due the a bit a current in the mppt controller components . Some inverters show a few volts as well 

Edited July 11, 20241 yr by GMAC

30 minutes ago, GMAC said:

It's normal for most Inverter to show a few Wats , don't think it's the panels generating any Wats but the inverter showing Wats that's not really then due the a bit a current in the mppt controller components . Some inverters show a few volts as well 

Volts seems to be normal due to some other sources but normally it collapses if trying to draw any current. 

This is my array voltage 0 current 0 but shows 1 watt.

Hi

Considering that clouds reflect infrared light, one notices the voltage of the arrays being ever so slightly higher on overcast nights. 

My array is 18V on a clear night and around 38V when it is overcast(5W).

Cheers

 

Edited July 11, 20241 yr by ZS1SCI

One way would be is for someone to disconnect the PV from the inverter and measure the volts with an multimeter that's  coming from the panels to determine if it's the PV generating a small amount of volts or just the inverter reading internal volts .

I would do it but I'm not home for 2 weeks . 

Scorp007 I have seen this with synapse 3+ inverter were it stores all the energy internally for some time after sun set . 

Here are 2 inverter of many that I can shear that also show constantly volts through the night 

 

 

Edited July 12, 20241 yr by GMAC

1 hour ago, GMAC said:

One way would be is for someone to disconnect the PV from the inverter and measure the volts with an multimeter that's  coming from the panels to determine if it's the PV generating a small amount of volts or just the inverter reading internal volts .

I would do it but I'm not home for 2 weeks . 

Scorp007 I have seen this with synapse 3+ inverter were it stores all the energy internally for some time after sun set . 

Here are 2 inverter of many that I can shear that also show constantly volts through the night 

 

 

Interesting that there is 200mA flowing. I have tried with a LED torch and you find a voltage say 6V but when adding even a 30mA load it just collapses. 

During summer I got quite a shock when I saw my multi reading power meter coming on at night with each lightning strike until I realised it's just the light on the panel. 

5 hours ago, Scorp007 said:

Interesting that there is 200mA flowing. I have tried with a LED torch and you find a voltage say 6V but when adding even a 30mA load it just collapses. 

During summer I got quite a shock when I saw my multi reading power meter coming on at night with each lightning strike until I realised it's just the light on the panel. 

Yip it's interesting how some inverters work differently to otheres that small amount of volts  through the night I have always thought it to be a small amount of leak in the inverters components but it could be othere reasons . Interesting what ZS1SCI said 

1 hour ago, GMAC said:

Yip it's interesting how some inverters work differently to otheres that small amount of volts  through the night I have always thought it to be a small amount of leak in the inverters components but it could be othere reasons . Interesting what ZS1SCI said 

I have also seen on cloudy evening the sky seems to contain more light than when there is no clouds. 

I normally disconnect my panels when testing the voltage so inverter has no affect. 

Also my night voltage jumps around real quick between about 40-450mV.

If I look at my weather station data and the pv voltage it nicely correlates with when the rain comes pouring down. 

 

I've attached a graph that breaks down solar radiation and it shows waters willingness to absorb infrared. 

If i read correctly online on a good day we use about half the infrared light to make power plus 43% which is visible light. 

Pew

 

Ps. I have to add, the infrared at play here is purely from the urban surroundings, tar, houses, etc.. 

 

Edited July 12, 20241 yr by ZS1SCI