What happens to MPPT if it receives more than rated max solar power (amps and/or voltage)?
asked
Overpowering MPPT
It will almost certainly fail and is not covered by the warranty. Ensure you size the panels correctly using the available tools and take into account the input voltage at all temperatures, ensuring it always remains within the specified operating parameters of the device. No components are serviceable so not sure why you would ask the question?
Voltage is the killer. The MPPT controls the amps. Except for lightning and short circuits. So don't exceed the Isc rating of the MPPT in your panel setup.
Generally the Wp do not realy matter.
As long as you do not exceed the maximzm Voc in a cold sunny winter day, you can put even 5600Wp modules on a SmartSolar MPPT 250/100 with only a 24V battery. The SmartSolar simply limit the output current to 100A or rate ircdown it it become too hot.
On the PV side you will onky see an enormous Voltage increase, because the SmartSolar simply can not take the whole energy.
However, the over powered SmartSolar has then an advantage in the Winter.
Thanks for all the replys! Just wanted to be sure about the voltage. It would be nice to have more panels from autumn to early spring, but it would then require some kind of switch to be able to disconnect additional panels for peak solar season.
You can add more strings up to max amperage. That takes care of low light conditions.
As
@Alexandra said.
Your existing panels should have solar isolator switches. Same for extra strings. Make sure all strings identical. Don't turn the switches while charging. Wait until night.
I have 2 panels now and space for one more, so doubling doesn't work...
What is your Battery Voltage and how many Wp do the panels have?
There are people which use three 650Wp in series but use a SmartSolar MPPT 250/70.
I use 5S (=2050Wp) on a 250/100
You could put 3 of the 410Wp modules in series and you could put up to 3 strings in parallel if we assume that your module outputs 14.01A Isc. I am assuming that the Isc is around 14A because the Voc is so low at 37.4 Voc.
Keep in mind when you have more than 2 strings in parallel you need to add fuses. In total you would have 3,690Wp. Personally I would not recommend adding another string and putting a disconnect there to manually add or subtract a string based on the season. It would be tough to manually define exactly what day to deactivate it and activate it. If you are looking to expand in the future it may be better to consider just buying another controller and adding more panels to that one.
14.01 x 3 = 42.03A This would be acceptable as Victron states that the controller can accept up to 50A Isc.
14.01 x 4 = 56.04A This would NOT be acceptable as Victron states that the controller can only accept up to 50A Isc.
Aaron
This thread is going in circles.
Your controller will handle three of these panels in series. If the total Is of the panels is less than the controller value, you could also wire in parallel. But don't exceed the max of 30A for the MC4 connectors.
In series you're dealing with dangerous voltages. It will be best to seek someone local who's qualified to assist to ensure a safe, functional system.
Victron actually recommends oversizing the solar array with relation to the charge controller due to the fact that you will almost never be charging at the peak power output of the modules. However you must never exceed the maximum voltage rating of a charge controller and the maximum input current rating. For example the charge controller 150|35 blue/smart solar has a maximum of 150 volts DC input. If the voltage exceeds 150VDC you will almost certainly damage the controller permanently. In the datasheet Victron mentions this and it also shows a maximum input current of 40A that would also damage the controller if exceeded. So never exceed 150V and 40A input for the 150|35 controller. Victron also has an excel sheet that helps you calculate this on their website at the bottom of this page. You input your solar modules parameters and it will tell you if your configuration is acceptable for the chosen controller.
hope this helped!
Aaron
here is the page, not sure why my hyperlink didnt work
https://www.victronenergy.com/support-and-downloads/software
