The main selection criteria for an excavator are its size and power. The size of a machine is characterized by its working weight (for example, we can say: a 10-ton excavator). Available in a variety of sizes, from the smallest models of less than 1 ton to surface mining excavators greater than 100 tons.
You need to choose an excavator that suits your needs, a model that is too small may not do the job required, and a model that is too large may be unwieldy and more expensive.
The weight of the excavator can give an idea of the overall size of the machine, but it is important to ensure that the robotic arm can reach the maximum distance it has to work. Most manufacturers provide diagrams in their technical documentation that represent the motion of the robotic arm to indie the maximum height and depth that can be achieved.