Setpoint Value Generation In Steps (Sost) - DEMAG DIC 002 Series Operating Instructions Manual

8.6

Setpoint value generation in steps (SOST)

Operating principle, general information
All reference value step functions are activated when current flows through the relevant input. The input signals
are filtered by the hardware and software.
An edge from "Off" to "On" must be created following the ready for operation signal in order to obtain a valid set‐
point value.
Edge evaluation is only possible if the inverter is ready for operation. Edge signals given too early will not be
detected and have to be repeated.
Reference value step function
The steps do not work on the basis of summation. A lower value can be programmed for a higher step than for a
lower one. The current setpoint value is always specified by the highest step that is switched on.
When the first step SW-Step 1+ 68 is applied, the inverter accelerates up the Acceleration 420 ramp to the
frequency value programmed for the SOST step 1 480 parameter. If a signal is applied to the (SOST) Step 2
66 input in addition to the SW-Step 1+ 68 input, the inverter will accelerate or decelerate up to the frequency
value of the SOST step 2 481 parameter. The signal must remain applied to the SW-Step 1+ 68 input to ena‐
ble higher steps to be activated.
If no signal is applied to the SW-Step 1+ 68 input any longer, the inverter will decelerate down the
Deceleration 421 ramp to 0 and will switch off the output stage.
If a signal is applied for the opposite direction SW-Step 1- 69 before zero is reached, the inverter will accelerate
in the opposite direction after reaching 0 without switching off the "Release brake signal".
The setpoint value step function works in the "–" direction in the same way.
If both SW-Step 1+ 68 and SW-Step 1- 69 inputs are activated simultaneously, the inverter will evaluate this
status as an invalid setpoint value. This response corresponds to the status as though neither of the inputs were
active.
SOST input assignment (default)
The following table shows the assignment of the digital inputs when the unit is delivered. The assignments can be
freely re-programmed.
Parameters
No. Name
68 SW-Step 1+
69 SW-Step 1 -
66 (SOST) Step 2
Tab. 69
SOST: associated parameters
Parameters
No. Name
480 SOST step 1
481 SOST step 2
Tab. 70
The Frequency Limits and Frequency Ramps apply, see  Tab. 61, Page 62.
For further information (SOST step 3 and SOST step 4), see "Dedrive Compact STO frequency inverter applica‐
tion notes/operating instructions".
68
Unit Min.
Control Inputs/Outputs ➜ Digital Inputs
Unit Min.
Reference Values ➜ SOST-Parameters
[Hz] -300,00
[Hz] -300,00
Setting Explanation
Max. Default
71 - S2IND
72 - S3IND
75 - S6IND
Setting Explanation
Max. Default
300,00 5,00 Input (SOST) Step 2 = 0
300,00 50,00 Input (SOST) Step 2 = 1