Instruction manual

14
4. ACCESSING DRIVE DATA
(1) This option unit acts as a Modbus Plus slave to a PLC or equivalent
controller acting as a Modbus Plus master.
This means that the option unit:
• Acknowledges messages received
• Transmits messages at the request of a network master.
(2) The option unit can also act as a Modbus Plus slave to a Modbus Plus
master that can read the drive's I/O values, as well as configure the
drive itself.
(3) The option unit cannot send messages on its own, and it has no bus
access rights. It also cannot simultaneously act as a slave to network
master and as a lead drive (master) to follower drives (slaves).
(4) This option unit does not support any other manufacturer-specific
messages or parameters.
(5) The Modbus Plus network is designed to allow individual devices to be
taken off-line without affecting the other devices on the network. For
example, if an invertr exists on a Modbus Plus network consisting of a
master and 1 or more other slave devices, deactivating or disabling the
master will not result in a Modbus Plus network error; therefore, the
inverter will not experience a fault and will continue to run based upon
the last valid commnad received.