User's Manual

LX-80 User Manual
Page 8 of 32
3.1. Serial RS-232 interface
Serial RS-232 interface is implemented as standard PC full-duplex serial interface
with voltage levels adequate for direct connection to PC computer or other embedded
device used for serial RS-232 communication.
In case RS-232 interface is connected to standard DB-9 PC connector, TxD line
(green wire) is connected to pin 2 and RxD (yellow wire) is connected to pin 3. For proper
operation of serial interface additional connection of signal GND (grey wire) is required
on pin 5 of the DB-9 connector.
Optionally Geolux can supply cable with DB-9 connector connected to the cable but
this must be specified as option on order of the sensors.
Several communication protocols are available, and custom on request. Details of
communication protocols are described later in this manual.
3.2. Serial RS-485 interface
Serial RS-485 interface is implemented as standard industrial half-duplex
communication interface. Communication interface is short-circuited and overvoltage
internally protected. Depending on the receiving device interface can be used with only
two wires (D+ dark red wire & D- orange wire) or in some cases ground connection
(signal GND gray wire) is also required. For more details please consult receiver
specification.
Most common communication protocol used with RS-485 interface is Modbus-
RTU, but other protocols are also available. Details of communication protocols are
described later in this manual.
3.3. CAN communication interface (optional)
CAN communication interface is optional communication interface that can be
used for special applications. This interface is higher speed interface (up to 1Mbps) than
other serial communication interfaces so enables additional data transfer not possible with
RS-232 and RS-485 interfaces.
CAN interface is disabled in default sensor version and for additional features using
CAN interface please contact technical support.