Bug in MainFaceplate for function block SignalOutBool?
The problem is that outputs in our safety system is set to "Latched on short mode", thus switching off the output with a short-circuit and locking it with channel error. The way to reset the error is to fix the short circuit and then force the output low. As mentioned, this resetting is not possible in the PG2 faceplate.
We are about to upgrade from 5.1 to 6.0 (or possibly 6.1). I assume Visual basic faceplates are not present in version 6.0 and forward. Is the bug (?) in the PG2 faceplate fixed? Any workarounds if not?
I have used many project/client libraries built upon the ABB libraries over the years and I cannot remember this being an issue. I taken a look at our project library and its faceplate ignores the IO status so this is not a problem for us. Other libraries I have used must have been similarly designed.
You have me curious now as to how one would get past this if using ABB's base libraries.
I know you can right click on the Controller tree when online in Control Builder, or in the control structure, and select Clear Latched Unit Status. I'm unsure if this would clear a short-circuit latch though on a safety controller? I don't have access to a live system to try this out.
If there are no other means to reset things you may be forced to create a custom faceplate, or override the SignalOutBool faceplates and remove the status condition that is holding you out.