# Electric Current Flux Through Surface
**URL:** https://discourse.paraview.org/t/electric-current-flux-through-surface/6197
**Category:** ParaView Support
**Created:** [January 10, 2021, 9:53pm UTC](https://discourse.paraview.org/t/electric-current-flux-through-surface/6197 "2021-01-10T21:53:45Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@modelman](https://discourse.paraview.org/u/modelman)
#### Post date: [January 10, 2021, 9:53pm UTC](https://discourse.paraview.org/t/electric-current-flux-through-surface/6197/1 "2021-01-10T21:53:45Z")
I have obtained the electric current **density** (flux density) from an Elmer 3D finite-element model. My objective is to calculate the current through a plane defined in the model. Here is what I tried:
1. In Paraview, I opened the vtu results file from the 3D solution.
2. Selected the current density data variable of interest from the vtu file.
3. Defined a plane in the 3D model by applying the **slice filter** to (2).
4. Applied the **surface flow filter** to (3).
The problem is that the bounds for the surface integration, as shown in the **surface flow** output, on the defined plane has **zero range**. Explicitly selecting cells in the plane produced the same zero range.
Any help/suggestions/comments regarding calculation of flux through a surface would be greatly appreciated.
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### Author:  [@modelman](https://discourse.paraview.org/u/modelman)
#### Post date: [January 11, 2021, 8:26pm UTC](https://discourse.paraview.org/t/electric-current-flux-through-surface/6197/2 "2021-01-11T20:26:37Z")
I realized what I had to do:
vtu data --\> slice --\> **cellsize**
All cells are now listed in the spreadsheet, and the data can easily be used to calculate the total current through the slice.