15
Example 8: Programming of an interlocking
logic. This example is related to example 3, the
circuit breaker is to be controlled.
The following rules are given for the interlocking:
- Opening of the circuit breaker is always al-
lowed.
- Closing of the circuit breaker is allowed when
the CB truck is in the isolating position or in
the service position and the earth-switch is
open.
Instead of these written interlocking condi-
tions, a logic diagram can be used:
Fig. 9. Simple logic diagram for the interlocking
logic for example 8
Below a detailed logic diagram is drawn.
Fig. 10. Detailed logic diagram of the inter-
locking logic for example 8
The actual commands are written on the basis of
the detailed logic diagram. As a default the
program area M200…M300 is filled with END
commands. The interlocking commands given
by the operator are written over these END
commands.
A configuration was programmed in example 3.
If the interlockings described above are taken
into use the programming continues with the
following commands.
>99WM200:LOAD 61:XX
; Read the value of special register 61
(the value is always 1)
>99WM201:OUT 20:XX
; Always enable the open command of
the CB
>99WM202:LOAD 1:XX
; Read the closed status of the CB truck
>99WM203:AND 203:XX
; Read the open status of the earth-switch
>99WM204:OR 201:XX
; Read the open status of the CB truck
>99WM205:OUT 21:XX
; Enable the close command of the CB
>99WM206:END:XX
; End of interlocking program
>99WS198:1:XX
; Change interlocking program into run
mode
>99WS199:1:XX
; Enable interlockings
>99WV151:1:XX
; Store the programmed parameters
The program is automatically compiled, when
changing back into the run mode. If there are
syntax errors in the program, the compiling will
not be passed and the interlocking stays in the
program mode. First the syntax errors must be
corrected and then the interlocking system can
be changed into the run mode.
The interlocking program can be by-passed in
two ways;
- For testing purposes the switch SG1/1 on the
front panel can be turned on. Then the inter-
locking program is interrupted and opening/
closing of an object is always enabled.
- If the interlocking logic is to be taken out of
use permanently , then variable S199 can be
set to 0. Then the opening or closing of an
object is always enabled.
The interlocking system does not affect the
tripping signal of the protection.
ENABLE TO OPEN CB
ENABLE TO CLOSE CB
1
ALWAYS
ES OPEN
CB TRUCK
OFF
&
1
CB TRUCK
ON
1
1
&
61
20
21
203
1
; ENABLE TO OPEN CB
; ENABLE TO CLOSE CB
201
To Next Page
Loading...
