Basic Function Principles
The analog output terminals
- KL/KS4414 and KL/KS4418 generate signals in the range 0 mA to 20 mA
- KL/KS4424 and KL/KS4428 generate signals in the range 4 mA to 20 mA
with a resolution of 12 bits (4095 increments). The actuators are supplied via the voltage fed from the power contacts. The power contacts can optionally be supplied via the standard supply or via a power feed terminal with electrical isolation.
Format of the output values
In the delivery state the process data are shown in two's complement form (integer -1 corresponds to 0xFFFF). The feature register R32 can be used to select other display options (e.g. signed amount representation, Siemens format).
Output value | Output current | ||
|---|---|---|---|
hexadecimal | decimal | KL/KS4414, KL/KS4418 | KL/KS4424, KL/KS4428 |
0x0000 | 0 | 0 mA | 4 mA |
0x3FFF | 16383 | 10 mA | 12 mA |
0x7FFF | 32767 | 20 mA | 20 mA |
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 are 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 for D/A converter |
|
Ba, Aa: | Manufacturer gain and offset compensation | (R17, R18) |
Bh, Ah: | Manufacturer scaling | (R19, R20) |
Bw, Aw: | User scaling | (R33, R34) |
The equations of the straight line are enabled via register R32.