This article presents a study on low-power passive current transformers. In particular, the performance of three Rogowski coils has been assessed when multiple influence quantities were acting on them: conductor position, frequency, and ambient temperature. First of all, their single effects have been assessed, then all their possible combinations have been tested. From the results, it can be concluded that the ratio error is mostly affected by the combination of uncentered positions and temperatures applied to Rogowski coils. Contrastingly, the phase error is substantially not influenced by any quantity. Therefore, the proposed set of tests could become a benchmark in Rogowski coil testing.