Extra 3 panels

I installed 3 extra panels but when I plugged them in to the inverter the power dropped from the other panels! Can anyone please inform me why?

SmithEN6 Were you adding these to an existing string? Are they the same output as the other panels? Are they facing the same way as the other panels? Are they in shade with the others in sunlight?

Tim I have 2 strings of 7 panel, the extra 3 panels were added to one of the strings.
They are not the same output my existing are 385w the extra 3 are 335w each, and they face the same way and are not in the shade but some on the existing panels are.

SmithEN6 all panels in a string will produce the same current as the current of the lowest panel, so that would be why you're seeing lower performance across all panels.

If

If that is the case is there a solution?

Does your inverter support dual mppt's? If so then you can move the orignal panels onto mppt1 and the new panels onto mppt2. I have just had this done on one of my systems to make use of 8 older 295w panels and added 11 new 400w

It depends...

Mixing solar panels is a very complicated issue and there are dangers too. The ability of the inverter to handle the myriad of possibilies is the main issue. Older inverters will crucify output when adding lower power panels. But it's not just about the wattage. Voltage and Current play a part too. Different panels may also respond to shading and panel temperatures too. Many newer panels are 'half cut' which are much more tollerant of partial shading.

Take a look at https://solarpanelsvenue.com/mixing-solar-panels/. There are plenty of other resources on the net that will help you understand the issues but this one is pretty good at getting the basics across.

Unless you can add these panels to your existing array/inverter setup with a net gain I wouldn't bother but maybe repurpose them for someting else. I assume you picked them up cheap - or you would have bought matched panels. In which case maybe not much has been lost. Maybe if you can get some more of the same add another inverter and add them that way. You don't say what inverter you have but some will support more than two strings and strings of differing specs - check yours if it's not GE.

Thank you for you time.
Instead of using a Y piece to connect to the inverter I removed the Y connector and joined the 7 string to the additional 3 so it would be a string of 10 and bingo it worked and I have an addition 30%.

I don't think you can put solar panel strings in PARALLEL like that (i.e. your Y connector). This would cause the voltage of the original string to be pulled down - hence your loss of power.

By putting the extra 3 panels in SERIES you have increased the voltage, which is what you needed. However, you now need to make sure that the maximum voltage from the string (on your best summer day) does not exceed the upper voltage limit of your inverter, so best check the specifications sheets......