Cattron-Theimeg LRC-L1, User Manual

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User Manual LRC-L1
Version 1.0.0 - 11/2010 Subject to change without notice. 7
3 General
With a transmitter and a matching receiver unit a device such as a crane, a machine or a vehicle can be
radio controlled, thus avoiding the need for a wired connection between the human interface and the device
to be controlled. Over a number of different control elements in the transmitter housing commands to the
device are initiated by processing the signals and generating a RF signal that is cyclically transmitted to the
corresponding receiver unit.
3.1 Radio Transmission
The transmission between the transmitter and receiver is done by means of radio communication. With
regard to the actual radio frequency that is being used, there are several radio frequency bands available.
Within the respective frequency band a specific RF channel must be selected. Depending on the frequency
band a certain number of RF channels are available. For details regarding the available RF channels please
refer to the RF-Channel-Tables in this document. Transmitter and receiver must operate on the same RF
channel in order to be able to communicate
3.1.1 Continuous Transmission
One of the features of an industrial radio remote control system for safety-relevant applications such as
machine controls is that it is ensured, that a permanent connection between the transmitting and receiving
station exists. For this, the receiver unit constantly monitors the RF channel to verify that a communication
link exists. Should the receiver not receive a valid telegram for a certain period of time (PNH-Time), it will
automatically turn off, i.e. safety relays and command relays open. Depending on the application, the PNH-
Time varies from 0.5 s to 2.0 s.
3.1.2 Area of operation
In order to ensure optimum communication between the transmitter and the receiver unit, the transmitter
should be operated ideally with line of sight to the receiver or its antenna at all times. Any shielding by
metallic constructions should be avoided.
3.1.3 Radio Interference
Signals from other RF emitting sources might interfere with the radio communication between the transmitter
and receiver unit. If the radio link is affected by these sources, changing the RF channel or even the RF
band might be necessary.
3.2 System Address
In an industrial radio remote control system, each transmitter/receiver pair shares a common, unique system
address. This system address is contained in every telegram sent by the transmitter and is checked by the
receiver every time a RF signal is received. Only when the address in the telegram and the address stored in
the receiver match, the receiver processes a command. This is a safety measure to ensure that the receiver
will act only upon its assigned transmitter. The system address is stored in the TransKeys, please see below.
3.3 System Parameters
The system parameters including the system address and the selected RF channel are set by programming
the TransKey. It is a removable RFID (radio frequency identification device) located inside the transmitter
and receiver unit. It is programmed by the manufacturer.
NOTE
!
Please refer to the separate 'Configuration Data' documents for the specific system parameter
settings of your system.
Figure 1: Transmitter TransKey (black)