©Sealevel Systems, Inc.
SL9049 - 06/2011
SeaI/O Manual
11
Base Modules connect to the host via one of the following interfaces:
W-Series – Wireless Modbus TCP
E-Series - Ethernet Modbus TCP
U-Series - USB Modbus RTU
M-Series - RS-485 Modbus RTU
S-Series - RS-232 Modbus RTU
After the base unit is installed, up to 246 additional SeaI/O N-Series Expansion Units
can be added
to create an I/O network. These expansion modules interface via RS-485 and can be located local to
the Base SeaI/O device or remotely located up to 4000 feet away. Local installations should use the
5” CAT5 RS-485 pass-through cable (Part# CA239) shipped with each N-series module to connect.
Remote expansion modules should use RS-485 twisted pair wiring from the base unit connected via
the removable screw terminal connector.
For local installations power to the expansion modules is supplied from the Base unit via the pass-
through connectors. For remote devices, separate power is required at each expansion unit. Refer
to the Power Options section of this manual for more information on SeaI/O power requirements
and power supply sizing.