One of my students wrote a basic motion program as a lab assignment.
The lab asked him to change the speed from % to seconds. He used 10.0 seconds as a time value.
J P[1] 10.0sec CNT100
J P[2] 10.0sec CNT100
etc.
The manipulator moves almost imperceptibly. Displaying World position in separate window shows small changes happening in the decimal parts of X, Y, and Z position values.
Increasing or decreasing the time values has no effect.
If the speed values are replaced with 50% speed, the program operates in a more normal fashion.
If the 10.0sec program is run in AUTO, it operates as it would be expected.
Robot is a ER-4iA / R-30iB Mate Plus. HandlingTool V9.30P/21 installed; a second identical robot has V9.30P/20. The program acts the same on both robots.
I have looked at DCS configuration but cannot find any relevant settings that are active that would explain the behavior.