I try to make a electrostatic sensor - a mini field mill, but i get a problem now. it is react when elecrtrostatic occurs or a item be charge and moving. How can it continuous react when a item be charged and static
I've deleted your other cross post @kmail82617.
Cross posting is against the rules of the forum. The reason is that duplicate posts can waste the time of the people trying to help. Someone might spend 15 minutes writing a detailed answer on this thread, without knowing that someone else already did the same in the other thread.
Repeated cross posting will result in a suspension from the forum.
In the future, please take some time to pick the forum section that best suits the topic of your question and then only post once to that forum section. This is basic forum etiquette, as explained in the sticky "How to use this forum - please read." post you will find at the top of every forum section. It contains a lot of other useful information. Please read it.
Thanks in advance for your cooperation.