It is from the Kenwood CAT manual, which is attached to this message.
It was interesting to hear that using the TS-480 from Hamlib enabled power on as those commands are the same for the TS-480 and the TS-590 radios.
Seems apparent that the difference is in the Hamlib radio definitions and that the TS-590 version could use some updating.
73 - Mark - K8MHW
'A RigPi Enthusiast!' - I am not otherwise affiliated with MFJ or RigPi