Omron NSH5, Operation Manual

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Removable Box Application Examples
Appendix E
(4) The NSH5 is no longer connected, so DM00200 changes to 0.
(5) Connect the NSH5 to Removable Box 1 and turn ON the Removable Box's key switch. The NSH5 will
start. The number 1 is stored in Station Status Monitor Address, $W1000.
(6) Next, $SB1 is turned ON, and the “When a bit changed” macro is executed.
The code “WRITECMEM(SERIALA:DM00200,$W1000,1);” writes 1 to PLC address DM00200.
The code “SHOWPAGE($W1000);” changes the PT display to the screen for station 1 (screen
number 1).
Detection Method for NSH5 Disconnected Status
When the NSH5 is not connected to any Removable Box, the station number sent to the PLC must be cleared.
Use one of the following methods to clear the station number.
• Monitoring the signal from the terminal block
• Monitoring $SB0 and $SB1 in NSH5 system memory
• Monitoring the Signal from the Terminal Block
I/O connected to the Removable Box's terminal block terminals CONECT1 and CONECT2 turn ON while
the NSH5 is connected to the Removable Box and turn OFF while the NSH5 is not connected. Therefore,
add programming to the ladder diagram so that the PLC clears the station number stored in DM00200
when the I/O turns OFF.
• Monitoring $SB0 and $SB1 in NSH5 System Memory
While the NSH5 is operating, $SB0 in system memory is periodically turned ON and OFF and $SB1 is
always ON. As a result, if the NSH5 and PLC are connected, the PLC address allocated to $SB0 is also
periodically turned ON and OFF.
Therefore, add programming to the ladder diagram so that the PLC clears the station number stored in
DM00200 when the PLC address allocated to $SB0 does not change for a specified period of time (indicat-
ing that the NSH5 and Removable Box are not connected).
PLC
Power OFF
NSH5
DM00200 = 0
Station 1 Station 2 Station 8
...
The PLC clears DM00200.
PLC
NSH5
Station Status Monitor Address $W1000: 0
→
1
DM00200 = 1
Station 1 Station 2 Station 8
...
Screen
0
→
1
SHOWPAGE($W1000) changes to screen no. 1.
WRITECMEM([SERIALA:DM00200],$W1000,1);
writes "1" to DM00200