Lenze DDS Function library Drive - Manual (Page 82)

2.7.3 Motor potentiometer (L_MPOT)
Function library LenzeDrive.lib
Special functions
2−72
L
LenzeDrive.lib EN 1.7
Activation of the motor potentiometer
·
If bInAct_b = FALSE, then the motor potentiometer is activated. The function that is now
performed depends on
– the momentary output signal.
– the preset limit values.
– the control signals at bUp_b and bDown_b.
·
If the signal at nOut_a
– is outside the limits that have been set, then the output signal moves to the nearest limit,
using the T
i
times that have been set. The sequence is independent of the control signals at
bUp_b and bDown_b.
– within the limits that have been set, then the output signal moves according to the control
signals at bUp_b and bDown_b.
2.7.3.2 Initialization of the motor potentiometer
On initialization after power−on, the motor potentiometer is loaded with a specific initial value. Under
byInitFunction you can select the initialization function.
byInitFunction Function
0 The output value that is output on power−off, is stored in the internal non−volatile memory of the drive controller. This
value is loaded in again at power−on.
1 On mains power−on the lower limit (defined by nLowLimit) is loaded.
2 On mains power−on an initial value = 0 % is loaded.
2.7.3.3 Storing the current output value after supply interruption
L_MPOT
nOut_a
bUp_b
bDown_b
byInitFunction
byFunction
bInAct_b
dnActRetain
CTRL
nHighLimit
wTir
wTif
nLowLimit
dnActRetain
[VAR_GLOBAL RETAIN] [VAR_GLOBAL RETAIN]
Fig. 2−72 Programming to store the current output value after a supply interruption
In order to store the latest value at nOut_a after a supply interruption, you must declare a global
variable of type RETAIN (VAR_GLOBAL RETAIN). Combine the variable as described in Fig. 2−72.
·
The current value at nOut_a is always stored in this variable. The variable will hold the value
after a supply interruption.
·
When the power is switched on again, the stored value is read into the FB L_MPOT from the
variable and applied as the starting value.