US Patent 9448257 Distribution line clamp force using DC bias on coil

A power distribution monitoring system is provided that can include a number of features. The system can include a plurality of monitoring devices configured to attach to individual conductors on a power grid distribution network. In some embodiments, a monitoring device is disposed on each conductor of a three-phase network and utilizes a split-core transformer to harvest energy from the conductors. The monitoring devices can be configured to harvest energy from the AC power grid and apply a DC bias to core halves of the split-core transformer to maintain a positive magnetic force between the core halves. Methods of installing and using the monitoring devices are also provided.