In Tendon → Axes, users are allowed to use “external geometry axis” such as REFX and SLN,
If the tendon point is referenced to the AXES REFX as shown in the above image, The tendon point belongs to Beam 1 or Beam 2?
There is a command in Tendon as “GRP” where one can set which groups should be searched for element finding by a given geometry in TGEO-command. For further information please see Tendon-manual , chapter 3.7.3 GRP – Group control