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 ( -1integer corresponds to 0xFFFF). Siemens output format 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:
Neither user nor manufacturer scaling is active
Ya = (Ba + XADC) x Aa | (1.0) |
Yout = Ya |
|
Manufacturer scaling active (default setting)
Y1 = Bh + Ah x Ya | (1.1) |
Yout = Y1 |
|
User scaling active
Y2 = Bw + Aw x Ya | (1.2) |
Yout = Y2 |
|
Manufacturer and user scaling active
Y1 = Bh + Ah x Ya | (1.3) |
Y2 = Bw + Aw x Y1 | (1.4) |
Yout = Y2 |
|
Key
Xadc: | Output values of the A/D converter |
|
Yout: | Process data to PLC |
|
Ba , Aa: | Manufacturer gain and offset compensation | |
Bh , Ah: | Manufacturer scaling | (Not implemented) |
Bw, Aw: | User scaling |
The equations of the straight line are activated via register R32.
Analog output channels
The analog output channels of the KL4494 generate signals in the range from -10 V to +10 V with a resolution of 12 bits (4095 steps). The outputs are single-ended outputs with a common ground potential.
Format of the output values
In the delivery state the process data are shown in two's complement form ( -1integer corresponds to 0xFFFF). Siemens output format can be selected via the feature register R32 as an alternative.
Output value | Output voltage | |
---|---|---|
hexadecimal | decimal | |
0x8000 | -32768 | -10 V |
0xC001 | -16383 | -5 V |
0x0000 | 0 | 0 V |
0x3FFF | 16383 | +5 V |
0x7FFF | 32767 | +10 V |
Process data equations
The process data, which are transferred to the Bus Terminal, are calculated based on the following equations:
Neither user nor manufacturer scaling is active
Ydac = X x Aa + Ba | (1.0) |
Manufacturer scaling active (default setting)
Y1 = Bh + Ah x X | (1.1) |
Ydac = Y1 x Aa + Ba |
|
User scaling active
Y2 = Bw + Aw x X | (1.2) |
Ydac = Y2 x Aa + Ba |
|
Manufacturer and user scaling active
Y1 = Bh + Ah x X | (1.3) |
Y2 = Bw + Aw x Y1 | (1.4) |
Ydac = Y2 x Aa + Ba |
|
Key
X: | Controller process data |
|
Ydac: | Process data to D/A converter |
|
Ba , Aa: | Manufacturer gain and offset compensation | |
Bh , Ah: | Manufacturer scaling | (Not implemented) |
Bw, Aw: | User scaling |
The equations of the straight line are activated via register R32.