New MPPT Calculator cannot do custom parameters!

DIY
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22

It has been a while since I originally posted to this discussion, but I wanted to give an update. The over paneling option is back in the new calculator, but it is not giving the actual functionality I think the users want (especially the less experienced users). The calculator allows for a PV Power Ratio up to 130% without the feature selection (by default). This is confusing to many users and is not always desirable. I have many applications where over paneling is acceptable, but I also have many applications where I do not want to over panel. I am aware the calculator will allow over paneling up to 130% by default so I pay attention to the PV Power Ratio calculation after I run the calculator for my applications. If the value is above 100% and I do not want over paneling for the specific application, I will step up to the next sized MPPT. Not all users know to do this. I have seen some posts on other solar groups from users complaining that the calculator recommended an MPPT too small for the application because it allowed over paneling (up to 130%) when the user did not want to over panel. This is not an uncommon complaint on the solar forums, but I just responded to a specific post where the user was very unhappy. The user was not aware the calculator allowed over paneling by default. In his real world application, this resulted in the MPPT derating and other issues due to heat build up once everything was installed. He ended up having to buy a second controller when a single larger controller could have handled the solar array if the proper recommendation was made (no over paneling) or if there was a better explanation on the calculator to indicate to him that over paneling was being recommended. I went to the calculator and played with the numbers and could not get it to stay at or under 100% PV Power Ratio no matter what I did. The calculator allows recommended over paneling up to 130% by default. When I used the “Allow Oversizing above 130%” slide switch, I could get a recommendation well above 130%. I pretty much never want to over panel above 130% so that option is not very useful to me (and I think many others). Ideally, I think I and others would like the calculator to recommend an MPPT up to 100% of its capabilities by default without allowing over paneling. I think the slide switch should allow for over paneling up to 130% when activated. Having an option to go over 130% does not seem very useful, but maybe some people want that ability. (I cannot think of a situation where I would want to have that much excess PV capacity connected to an MPPT.) It would seem to be quite wasteful to me. Hopefully this can be corrected. From my perspective, the default should be to not exceed 100% capacity, then have an option to go up to 130% capacity and maybe have a third option for the rare circumstance where going over 130% would be desirable (although again I do not see how useful this would be but maybe others need this).