From JHarbin:
That said, if it *was* working, then I don't think that the PLC is polling the BMS. As I mentioned earlier, that is the only way the DSPLE will actually make requests. That's why using the Watch Window works.
The data from the PLC tags connected to the data station are MOVEd into a different PLC tag on an unconditional rung. The PLC Heartbeat and the Slave "IsDeviceOnline & DeviceStatus" are working so I assume the PLC is polling the Redlion Data Station.
Woolie
I'm pretty sure that those tags only indicate that the DSPLE can talk to the BMS, not that it is actually polling the BMS to get data.