This will not spec the mounting components but will mean the pitch and orientation of the panels is correctly modelled in performance calculations. Get in touch with [Midsummer (UK)](https://midsummerwholesale.co.uk/) / [(IE)](https://midsummer.ie/) for guidance on mounting components.
# The mounting system I want to use isn't an option in the panels task, what can I do? If the mounting system you'd like to use is not listed in the panels task, select *No* mounting. Then in the [financial task](https://help.easy-pv.co.uk/books/financial-task/page/using-the-financial-task "Using the Financial task"), you can manually your mounting system so it's still included in the quote. If the mounting system you want to use is stocked by Midsummer (this includes [Van der Valk](http://midsummerwholesale.co.uk/buy/van-der-valk) and [K2 flat](https://midsummerwholesale.co.uk/buy/k2-flat-roof)), you can get in touch with your account handler for help with building the kit list. # I can’t allocate my panels to an inverter - all the options are red. When all of the allocation options are red, Easy PV has determined the panel/inverter combination is not electrically viable. This means that the technical specifications of either the panels or the inverter are out of the range of the other. When panels have been allocated to an input, Easy PV will outline any electrical issues in red text to make you aware of why it is not compatible. For a custom component this could mean one of the values you have input is incorrect 1. Select the option you think should be possible with the inverter and panel 2. See which option appears in red [](https://help.easy-pv.co.uk/uploads/images/gallery/2025-10/tblhyfT4aRgZVlbA-image.png) 3. Check that value against the datasheet, it may be helpful to reference our [component upload guide](https://help.easy-pv.co.uk/books/creating-components/chapter/create-and-manage-your-own-components "Create and manage your own components"). # The max voltage calculated in the inverter task doesn't match the Voc from the panel datasheet, why is this? The max voltage factors in both the **open circuit voltage** (Voc) and the **temperature coefficient** (ΔVoc/°C) of the panel. The value on the datasheet is measured at standard test conditions (STC) but the actual Voc of the panels will depend on the ambient temperature. As the temperature decreases, the Voc increases, so it is important to factor this into sizing the inverter. In Easy PV, we do a calculation at -10°C, since the voltage increases at lower temperatures, the max voltage given in Easy PV will be **higher** than the number of panels multiplied by the open circuit voltage of the panels.