Beckhoff KL4494, Manual

Page: 8 / 40

Product overview
KL4494 8 Version: 2.0.0
2.3 Diagnostic LEDs
The four green RUN LEDs indicated the operating state of the terminal channels.
Fig. 2: KL4494 - LEDs
Meaning of the LED displays
LED Color Channel State
On off
Run IN 1 green Input 1 normal operation A watchdog-timer overflow has
occurred. The green LEDs go
out if no process data are
transferred between the
controller and the Bus Coupler
for more than 100 ms.
Run IN 2 Input 2
Run OUT 1 Output 1
Run OUT 2 Output 2
2.4 Basic function principles
Analog input channels
The analog input channels of the KL4494 process signals in the range from -10 V to +10 V with 12-bit
resolution (4095 steps). The inputs are single-ended inputs with a common ground potential.
Format of the input values
In the delivery state the process data are shown in two's complement form ( -1
integer
corresponds to 0xFFFF).
Siemens output format [
}
34] can be selected via the feature register R32 as an alternative.
Measured value Input data
decimal hexadecimal
-10 V -32768 0x8000
-5 V -16383 0xC001
0 V 0 0x0000
+5 V 16383 0x3FFF
+10 V 32767 0x7FFF
Process data equations
The process data that are transferred to the Bus Coupler are calculated using the following equations: