Siemens SINUMERIK 840D sl Function Manual page 126

B3: Several operator panels connected to several NCUs, distributed systems - only 840D sl
2.2 Several operator panel fronts and NCUs with control unit management option
MCP switchover
The MCP switchover is not mandatory. It can be enabled or disabled via the FB101/DB101
variable: MSTT_enable. Assignment in the declaration table:
TRUE: MCP switchover is effective.
FALSE: MCP switchover is not effective, no FC103 call
The MCP assigned to the active PCU is always activated. If the operating mode switchover
function is disabled, then the MCP assigned to the last PCU to go online is activated.
Power-up condition:
To prevent the previously selected MCP from being activated again when the NCU is
restarted, input parameter MCP1BusAdr must be set to 255 (address of 1st MCP) and
MCP1Stop to TRUE (deactivate 1st MCP) when FB1 is called in OB100.
Enabling commands:
When one MCP is switched over to another, any active feedrate or axis enabling signals may
be transferred at the same time.
Note
The override switch of the new MCP is immediately effective following an MCP switchover.
The keys actuated at the time of the switchover continue to take effect. If no MCP is installed
on the newly selected PCU, then it will not be possible to cancel the key functions from the
PCU. Measures for situations of this type must be implemented in the PLC user program.
Operating mode switchover
The operating mode switchover is not mandatory. It can be enabled or disabled via the
FB101/DB101 variable aktiv_enable. Assignment in the declaration table:
TRUE: Operating mode switchover is effective
FALSE: Operating mode switchover is not effective, no FB102 call
Error messages
If disturbances occur (e.g. interface signal failure) while the program is running,
corresponding alarms/error messages are transferred to data block DB2. 6 alarms are
implemented:
1. Error in HMI bus address, HMI bus type
2. No confirmation HMI 1 offline
3. HMI 1 is not going offline
4. No confirmation HMI 2 offline
5. HMI 2 is not going offline
6. Requesting HMI is not going online
and an error message: Sign-of-life monitoring error
126
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
Extended Functions