Instead of the voltage at each node, EM analysis solves for current in each branch, and instead of a voltage limit, there is a current limit per wire, depending on its layer and width.
ɪnstˈɛd ʌvðə vˈoʊltɪdʒ æɾ ˈiːtʃ nˈoʊd, ˌiːˈɛm ɐnˈæləsˌɪs sˈɑːlvz fɔːɹ kˈɜːɹənt ɪn ˈiːtʃ bɹˈæntʃ, ænd ɪnstˈɛd əvə vˈoʊltɪdʒ lˈɪmɪt, ðɛɹ ɪz ɐ kˈɜːɹənt lˈɪmɪt pɜː wˈaɪɚ, dᵻpˈɛndɪŋ ˌɔn ɪts lˈeɪɚ ænd wˈɪtθ.