What's the meaning of x e.g 10 commands per second limitation in Modbus?
Does it mean that (whatever function code has been used) when master sends request slave will not permit more than 10 registers per second for the response?
A command is a Function Code sent by the Master/Client. I would interpret a limitation of "10 commands per second" as meaning that the master/client can not execute any given Function code command more often than every 100mS.
Executing another Function Code command 100mS after another would assume that the Master poll and slave response are complete within 100mS of the initiation of the master poll and that there is not a time out situation or a slave reply still in progress.