User's Manual

01/2001, CATTRON - THEIMEG
TM
Section 1, Page 5
Overview – CATTRON-THEIMEG
™
Remote Control Systems.
Figure 1-1 below shows a simplified block diagram of a typical CATTRON-THEIMEG
™
remote control
system. Refer to this figure and the following paragraphs for a functional description of the remote
control system.
The target receiver/decoder is controlled by the Pendant Station Controller. Provided the correct
coded ‘i-Key’ is inserted into the controller, the controller sends signals to the receiver/decoder using an
UHF radio link. The signal is picked up by the antenna and passed on to the receiver. If the signal is the
correct frequency and passes all required data tests, the signal is passed on to the decoder. The decoder
compares the address code of the signal to its own address code. If the signal’s address code does not
match its address code, it is ignored and a message is displayed on a system status display located in the
receiver/decoder unit. If the address code is correct, the decoder processes the message and energizes
and de-energizes the appropriate control, directional output, three-speed and auxiliary function relays
located within the control system.
An Automatic Safety Override (ASO) function continually monitors the state of all directional relay
outputs (i.e. Forward/Reverse). If a directional relay electrically fails closed without a command from
the controller, the ASO circuit logic de-energizes the master output relay (OPR).
During operation, the microprocessor on the decoder board resets multiple watchdog timer circuits
whenever valid messages are received and decoded. If the microprocessor fails to reset the watchdog
timers, the timer circuits shut down and de-activate all relay outputs. The decoder microprocessor
requires continuously valid transmitted signals to be received and decoded or all relay output functions
will be de-activated unless programmed otherwise. It should be noted that the mainline control relay
(OPR) would be maintained for up to 10 minutes, depending on system configuration.
Figure 1-1. Typical Radio Remote Control System, simplified block diagram
END OF SECTION
PENDANT
CONTROLLER
ADDRESS
ADDRESS
FREQ
FREQ
Rx
Tx
RECEIVER DECODER
12 VDC
POWER
SUPPLY
WATCHDOG
TIMER
115 VAC
50-60 HZ
DIRECTIONAL OUTPUT RELAYS
MACHINE WIRING
THREE-SPEED AND AUXILIARY
FUNCTION OUTPUT RELAYS
ASO