Downhole-Adjusting impact apparatus and methods

A method comprising:

• conveying a tool string within a wellbore via conveyance means, wherein the tool string comprises an impact apparatus previously adjusted for imparting to the tool string first and second impact forces corresponding to first and second tensions to be applied to the tool string via the conveyance means;
• then causing the impact apparatus to impart the first impact force to the tool string by applying the first tension while a voltage or current detectable by the impact apparatus is established via conductors within the conveyance means and the tool string;
• and
• then causing the impact apparatus to impart a third impact force to the tool string by applying a third tension while the voltage or current is removed from the conductors and, while maintaining the third tension, reestablishing the voltage or current detectable by the impact apparatus via the conductors;
• wherein the third impact force and the third tension are respectively greater than the first impact force and the first tension, wherein the second impact force and the second tension are respectively greater than the third impact force and the third tension, and wherein a component of the tool string other than the impact apparatus comprises an electrical apparatus powered by the voltage or current, such that:
• the first impact force is imparted to the tool string while the electrical apparatus is electrically powered by the voltage or current;
• and
• the second impact force is imparted to the tool string while the electrical apparatus is not electrically powered by the voltage or current.

A method comprising:

• conveying a tool string via conveyance means within a wellbore extending from a wellsite surface, wherein the tool string comprises:
• a downhole tool configured to be electrically powered, via the conveyance means, from surface equipment disposed at the wellsite surface;
• and
• an impact apparatus operable to detect whether the downhole tool is electrically powered;
• operating the conveyance means and the surface equipment to cause the impact apparatus to impart to the tool string one of a first impact force and a second impact force, wherein:
• the first impact force is imparted to the tool string when the impact apparatus detects that the downhole tool is electrically powered;
• the second impact force is imparted to the tool string when the impact apparatus detects that the downhole tool is not electrically powered;
• and
• the second impact force is greater than the first impact force.