How to Select PV modules for inverter?

[saadmubeen]

I was looking for inverters and I stumbled upon the attached link. If you look at the first model Axpert MKS 1k-24. The Maximum PV array size is 600w and vdc is 75volt. Now I have following questions.

What does Maximum PV Array Size mean? Does it mean I can maximum input 600w of panels to the inverter???


If the answer is Yes then I couldnt find the perfect combination to get 600w of panels with a total of 75vdc. The maximum closest i am getting is either 2 panels of 270w,37.5voc combination makes 540w,75vdc or 6 panels of 100w,21.6voc making 600watts,108vdc....Can the Vdc be crossed???

Am I on the right track? Do I need to search more in my locality to search for more combinations? Please guide. Looking forward for urgent replies?

One more Question is if you look at AXPERT MKS 3k-48 and Axpert 1k-48 both have same maximum PV array size i.e., 900 watts!!! How come???

I am having trouble to get the link to work...Please click on Specification after visiting the link.

http://www.voltronicpower.com/oCart2...product_id=132

[sensij]

Your understanding of maximum array size looks correct. It is not a good idea to allow Voc to exceed the Vdc max for the input. In fact, you should adjust the Voc for the minimum temperature in your location... if you are somewhere with a real winter, that adjustment could be +25%.

You are not likely to hit a combination that exactly maxes out both the PV array size and the voltage. As you've found, a pair of 60 cell panels could be a good match if it isn't cold. You can find 275-290 W 60 cell panels... LG makes 300 W panels, but they might not be available where you are.

The inverter they are selling is actually two separate components... a solar charge controller, and an inverter. The reason the 1k and 3 k inverters have the same input specs is because they are using the same charge controller components. The higher allowed discharge rate on the 3k inverter may be appropriate for some surge applications, but if it is only supported by 900 W of solar, you shouldn't expect to run more than 1 kW of load for very long.

[saadmubeen]

Your understanding of maximum array size looks correct. It is not a good idea to allow Voc to exceed the Vdc max for the input. In fact, you should adjust the Voc for the minimum temperature in your location... if you are somewhere with a real winter, that adjustment could be +25%.

You are not likely to hit a combination that exactly maxes out both the PV array size and the voltage. As you've found, a pair of 60 cell panels could be a good match if it isn't cold. You can find 275-290 W 60 cell panels... LG makes 300 W panels, but they might not be available where you are.

The inverter they are selling is actually two separate components... a solar charge controller, and an inverter. The reason the 1k and 3 k inverters have the same input specs is because they are using the same charge controller components. The higher allowed discharge rate on the 3k inverter may be appropriate for some surge applications, but if it is only supported by 900 W of solar, you shouldn't expect to run more than 1 kW of load for very long.

http://www.voltronicpower.com/oCart2...product_id=132

What is Rated Power? Rated power shown in the above link for Axpert 3k-48 model is 3000va/2400w and Axpert 1k-48 model is 1000va/1000w. But Maximum Array Power for both model is 900w. If maximum array power is 900w the batteries can generate maximum 700-750w in peak hour because of efficiency.... If Rated Power is Continuous Power the inverter can give then how come Axpert 3k-48 which is 3000va/2400w can give continuous power of 2400w!!!!????