Thank you for the mod.
Please, add the russian locale http://file.sampo.ru/nwzdw6/
I have to remove the translation from my translation mod, because it messes with the vanilla item name even when the RTG mod is not installed.

To provide consistent quality I no longer add translations I can't maintain myself to my mods.

You probably can fix your translation using

if mods["RTG"] then
  data.raw["generator-equipment"]["fusion-reactor-equipment"].localised_name = {"equipment-name.fusion-reactor-equipment", {"Uranium RTG"}}
  -- do the same for item, recipe and descriptions
end

Uh, the problem here is that I am not a modder. Not a bit. I don't event know where to write these lines.
Is there any chance that you change your mod locale IDs to non-vanilla values and add the mentioned code to your mod?

Changes to localised_name have to be done in the language pack.