These grids have a deployed part (the resistive part) and 2 solid bands (one at each end) to ensure assembly and connection. A shape can be given to the elements to improve their mechanical resistance. The choice of the type of element is based on the resistance value, the energy to be dissipated and the mechanical rigidity.
Assembly of resistive elements
The resistive elements are stacked on threaded rods and welded together for an optimal electrical connection.
Insulation between the resistance elements themselves and the rods is ensured
- or by ceramics for standard uses
- or by mica tubes and washers when the resistance is subjected to strong vibrations (railway traction resistance).
The resistant elements of expanded metal offer an optimal surface of dissipation either by natural convection or by forced convection.
The geometry of the resistant elements in expanded metal and the variety of meshes allow us to obtain resistive elements with a high precision of ohmic value.
The use of expanded metal elements allows in most cases to adapt to tight spaces and optimize the weight.
- Dynamic braking (forced ventilation or natural convection)
- High voltage grounding
- High power harmonics filtering
- Load banks
The different types of alloy used are:
- Ferritic steel
- AISI 304
- 18/10 stainless steel
- Refractory steel
- Cupro-Nickel Alloy