# \[Archive\] nbPointMinPot **URL:** \ **Category:** SPIS\ **Created:** [22 May 2018 23:06 UTC](https://forum.spis.org/t/archive-nbpointminpot/716 "2018-05-22T23:06:00Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![system](https://forum.spis.org/uploads/default/original/1X/887f7e402a70666bad1816db2c64fefd698b4b0f.png) [@system](https://forum.spis.org/u/system)\ **Post date:** [22 May 2018 23:06 UTC](https://forum.spis.org/t/archive-nbpointminpot/716/1 "2018-05-22T23:06:00Z")
Message by **Aldo** : Hello. I’m currently using SPIS-Dust and there’s a parameter in the Surface Interaction sheet who’s name is _nbPointMinPot_. There’s no description neither in the UI nor the online NUM manual ([\http://dev.spis.org/static/documentation/DocSpisNum/HowTo/Controlling%20NUM%20from%20UI%20-%20SPIS%205.html](http://dev.spis.org/static/documentation/DocSpisNum/HowTo/Controlling%20NUM%20from%20UI%20-%20SPIS%205.html)). Does anyone know what does that parameter do? Thank you Aldo ---
**Author:** ![system](https://forum.spis.org/uploads/default/original/1X/887f7e402a70666bad1816db2c64fefd698b4b0f.png) [@system](https://forum.spis.org/u/system)\ **Post date:** [20 September 2018 10:37 UTC](https://forum.spis.org/t/archive-nbpointminpot/716/2 "2018-09-20T10:37:00Z")
Message by **Sébastien Hess** : This parameter determines the number of points that are used to determine the depth of the potential barrier over the Moon surface in order to adjust the amount of solar wind to inject electrons so that quasi-neutrality is ensured at the top boundary of the simulation. To be used for quasi-1D simulations of the Moon (or asteroid) surface and with the electronFluxFromPhotoEmission interactor. Sébastien ---
**Author:** ![system](https://forum.spis.org/uploads/default/original/1X/887f7e402a70666bad1816db2c64fefd698b4b0f.png) [@system](https://forum.spis.org/u/system)\ **Post date:** [10 July 2020 12:59 UTC](https://forum.spis.org/t/archive-nbpointminpot/716/3 "2020-07-10T12:59:48Z")
Closed on 10 July 2020 12:59 UTC