@Valerie Thanks so much for your reply.

Tried out your attached file however that is not what I am after. What I am interested in is the outboard frame (flange_b) angle. If you refer to the _works file there the signal form the sensor is being fed back to one of the two <= blocks and the simulation completes without issue. My confusion is if two of these <= blocks are used then the error is given.

Michal