How to test engine strength

Hey guys,
i'll have a question. First of all sorry for my bad english .
But my question is, how can i test the strength (trust en how much it can lift) and what kind of things do i need to test it.

Thanks!

English looks good to me!

Typically one would want a load cell to test what you are looking for. However this is beyond the realm of most in the hobby. We simply trust the manufacturer ratings, at least within 10% or so. There are some exceptions, mostly those flush with funds and likely making their own motors.

Maybe this will help.

There are three organizations that certify rocket motors: the National Association of Rocketry, the Tripoli Rocketry Association, and the Canadian Association of Rocketry. These three organizations test and document every commercial rocket motor to ensure that its advertised specifications are accurate and consistent.

Every certified motor has a listed thrust rating. The thrust rating is general in Newtons. One Newton provides roughly 3.6 ounces of force. These three rocketry organizations also recommend a minimum of a three-to-one thrust-to-weight ratio for a safe launch; but most fliers prefer a much safer five-to-one ratio.

Therefore, to lift a 3.6 ounce rocket safely, one would want a motor with at least five Newtons of thrust. A simply spreadsheet can be crafted to indicate safe motors for varying weights of rockets.

This is how it is done by NAR S&T in the US. https://www.nar.org/wp-content/uploads/2014/08/ST-MotorTestingManual.pdf

Bob