GE VersaMax Manual page 132

VersaMax Expansion Modules Standard RS-485 Differential Expansion Interface
The Expansion Receiver Module connects to an Expansion Transmitter Module in a
VersaMax PLC or VersaMax NIU I/O Station, or to an Expansion Receiver in a
previous rack, as shown below. Modules are connected using expansion cable
IC200CBL6xx (xx represents the length in meters). Up to seven expansion racks can
be used in a system. With the isolated Expansion Receiver Module, the total overall
length of the expansion cable can be up to 750 meters.
15M with any
IC200ERM002 ERMs
750M with all
IC200ERM001 ERMs
Cable Length and Data Rate
By default, the module is set up to operate with the maximum length expansion cable
at the default data rate of 250Kbits/second.
If the total length of the expansion cable is less than 250 meters and there are no non-
isolated Expansion Receivers (IC200ERM002) in the expansion system, the
VersaMax PLC programmer allows the data rate to be configured to 1Mbit/second.
In an NIU I/O Station, the data rate cannot be changed from the default 250Kbits.
Terminator Plug
The terminator plug supplied with the Expansion Transmitter Module must be
installed in the lower connector of the last Expansion Receiver in the chain as shown
above.
GFK-1504K Chapter 6 Expansion Modules
IC200CBL601,
602, 615
Terminator
Plug
Expansion Receiver Module, Isolated
VersaMax PLC or I/O Station Main Rack (0)
ETM PS
CPU/NIU
VersaMax ExpansionRack 1
PS
ERM
VersaMax ExpansionRack 7
PS
ERM
6
IC200ERM001
6-9