Since parallel processors are generally constrained by the available interp ocessor data transfer capability, system designers generally try to push interconnection systems to their limits in bandwidth. Practical and economic systems are constrained by many physical and packaging considerations such as a need to use commercially available connectors. We describe here VisiSolve-a simulator that we have built to predict the behaviour of inter connect systems that can readily be assembled from "off-the-shelf" components. It uses a finite element approach and predicts the dynamic electric field in the cells of the mesh. The irregular geometries of the individual parts of such components require us to adapt the mesh used in simulations in regions where the needs of a practical connector-small size, low insertion force and automatic assembly-have dictated the shape and path of the conductors. We have adopted a method which uses the constitutive error-the discrepancy between electric fields calculated directly and from Δ x H when H was calculated directly-as an indicator that refinement is needed.