SENTRON PAC – Accessories. The measuring devices of the 7KM PAC series are used to measure and display all relevant network parameters in low-voltage distribution. They can be used for single-phase measurements as well as for multi-phase measurements in 3- and 4-wire networks. Accessories for the power monitoring device 7KM PAC include mounting adapters, pluggable I/O modules, pluggable communication modules, and current transformers with direct passage.