Parker LVD1 - Examples and Applications

Parker Hannifin S.p.A. - Divisione S.B.C. LVD User’s Manual
66
4.2 Examples and applications
The following examples illustrate possible functionalities obtained by suitable programming of
the LVD pico-PLC. The suggested solutions offer the possibility of reducing the components
required to build the machine or part of the machine while, in many cases, also cutting the overall
cost of the application. Note that the pico-PLC scanning time is 6.144 msec and the maximum
number of instructions is 128; moreover, the PLC is designed principally to manage the drive's
digital inputs and outputs.
In addition to a concise description of the application, the examples show the settings required
for LVD parameters and the pico-PLC program. The program is shown in ladder diagrams and
instruction lists.
Example 1: two inputs for on/off functions
Example 2: changing a parameter value with the up/down keys
Example 3: command on positive front of a digital input
90.1 90.2 91.2
91.2
LD
90.1
OR 91.2
ANDN 90.2
OUT
91.2
digital input 1 sets bit b91.2 to on
digital input 2 sets bit b91.2 to off
ADD
ADD
92 76 92
05 73 0590.1 99.0
ADD
ADD
92 76 92
05 71 0590.2 99.0
LD
09.1
AND 99.0
ADD 05.73.05
ADD 92.76.92
LD 90.2
AND 99.0
ADD 05.71.05
ADD
92.76.92
digital input 1 in high status increases
parameter Pr5 by one unit every 614
msec
digital input 2 in high status decreases
parameter Pr5 by one unit every 614
msec
LD
90.1
ANDN 90.10
SET 70.8
LD 90.1
OUT
90.10
digital input 1 sets bit b70.8 just once
when the signal changes from low to
high
SET
90.1 90.10
90.1 90.10
70.8