Question:
What aspects have to be observed when using Lenze function blocks with internal time constants?
Response:
If Lenze function blocks with internal time constants (i. e. with a continuous time response) are used in a non time-equidistant task like, for example, the cyclic task PLC_PRG, the blocks may indicate faulty values. The bigger the ratio task cycle time to time constant of the function block the larger the error. It must be assured that the function blocks are activated in time-equidistant cycles, e. g. in an interval task.
The following Lenze function blocks are equipped with a continuous time response:
Library LenzeDrive.lib:
L_PT1 Delay (analog signal)
L_DT1 Derivative-action (analog signal)
L_RFG Ramp function generator (analog signal)
L_SRFG Ramp function generator S-ramp (analog signal)
L_PHINT Integration (angular signal)
L_PHINTK Integration (angular signal)
L_MPOT Motor potentiometer
L_PCTRL Process controller
Library LenzeElectricalShaft.lib:
L_DFRFG Master frequency ramp function generator
L_DFSET Master frequency processing
L_REF Reference (Homing) function
Library Lenze9300Servo.lib:
L_MFAIL Mains failure control