How to transfer a variable from PLC_Connect to an Application/Diagram in Control Builder.
How do I transfer a boolean variables status (True / False ) from PLC Connect to a application/diagram in control builder? and vice versa?
see attached picture.
I know there is a aspect called "Property Transfer Definition" and i know how to write expression and got no errors when I "Verify" but it will still not work.
Is it right to use "property transfer def." ?
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Does your system have any Property Transfer service group and provider(s)? If not you must create them to "mother" your transfer aspects.
Be aware of the pitfalls with Property Transfer:
1) Be sure to not overload the destination OPC server. A write may take a significant time to perform, especially if the destination is high in load.
2) Be on the lookout for "Transaction Overrun" or "Write fail" in the System Event List which may be the first indications of 1)
3) Even if the transfer's Update Rate is set to a high value (to mitigate overload) the source OPC server may still deliver ALL subscribed items at once if they change value at the same time and previous update time is one update rate cycle or more in the past.
4) No write retries will be attempted on a failed write until next change at the source side (This will change from 5.1 FP4 RevD when failed writes are retried).
All together this tells that property transfer shall not be used for important signals that may cause damage to equipment, etc. if transfer is not getting through and that the destination should perform some kind of supervision on the transfer (e.g. a watchdog, using a triangular wave from the source, etc.).
1) I can see that there is a "Write Fail" in system event list (see PIC_2). How do I correct the OPC overload?
2) In this example I try to send a variable to PLC_Connect, the "property transfer def." aspect is created under the PLC_Connect object (See PIC_3). Where will I place the "property transfer def." aspect when I want to send a variable to a Control builder application variable?