README
Bill of Materials
-----------------

There is a single configurable spreadsheet in this folder that serves as
the BOM for all four versions of the PCB:
  
     IV_Swinger_2_PCB_BOM.xlsx

Near the top are two cells containing RED text that specify the PV type
and relay type.  Each of these cells has a pull-down list that
constrains its values.

     PV type: "PV module" or "PV cell"

    Relay type: "EMR" or "SSR"

--------------------------------------------------------------------------------
PCB name                PV type       Relay type
--------                -------       ----------
IV_Swinger_2_module:    PV module     EMR
IV_Swinger_2_cell:      PV cell       EMR
IV_Swinger_2_ss_mod:    PV module     SSR
IV_Swinger_2_ss_cell:   PV cell       SSR
--------------------------------------------------------------------------------

The items in the BOM that are dependent on the PV type and/or the relay
type change based on the values in those two cells.  Items that are not
present at all for the given configuration are shown with a quantity of
0 and are grayed out.

This folder also contains PDFs generated for each of the four
configurations:

   emr_mod_BOM.pdf
   emr_cell_BOM.pdf
   ssr_mod_BOM.pdf
   ssr_cell_BOM.pdf

Additionally, in ../GIFs there are animations that do pairwise comparisons:

   ../GIFs/emr_mod_vs_emr_cell_BOM.gif
   ../GIFs/emr_mod_vs_ssr_mod_BOM.gif
   ../GIFs/ssr_mod_vs_ssr_cell_BOM.gif
   ../GIFs/emr_cell_vs_ssr_cell_BOM.gif