This request for clarification deals with s/c "boundary" Logical Nodes which are connected to the process.
As soon as the mode of such LN is set to "blocked", "test/blocked" respectively, no (wired) output data (digital by relays or analogue setpoints) will be issued to the process.
It is not defined whether
the concerned outputs shall turn to their idle/default states or
the status of the concerned outputs shall be frozen in the present value.
Proposal
Consider transient and non-transient controls.
Proposal (for contacts):
-For transient controls the contact to assume its default position (open if normally open and closed if normally closed). Allow to finalize a control in progress at the time of activating "blocked" or "test/blocked" mode to prevent from intermediate equipment positions.
- For non-transient controls the contact to remain in its state.
Discussion
Created
Status
The wording of the new statement which will be added shall refer to both digital outputs and analogue outputs.
28 Jul 26
Discussion (red)
follwing the discussions within WG10 incl. TF 10-3, I propose to change the state to 'Approval (Future Improvement)'
28 Jul 26
Discussion (red)
See also discussion in redmine DB --> https://redmine.ucaiug.org/issues/6555
07 Feb 24
Discussion (red)
Blocked mode should de-energize the output relays.
Reason for that: Blocked mode can be used before restarting a device when uploading a configuration.
The new configuration may associate the digital output differently than current configuration.
Therefore "de-ernergizing" sounds like a deterministic safe state for the command to the output relays, regardless if the relays is being used for non-transient control or not.
21 Nov 23
Discussion (red)
Agree to add a line in Table A.2 and to complement the wording in Table A.1.
items to consider in the new statement:
- binary outputs (contacts)
- analogue outputs (current loops)
- LPDO LN class in preparation
- external DO connected via bus (intelligent terminals, intelligent breaker units, e.g.)
04 Oct 21
Discussion (red)
Just a correction of wording: we should use the terms like in part 7-3: persistent output and pulse output (OutputSignalKind).
We may consider a formal change in table A.2 of 7-4 or adding a row to distinguish "output to process" from software and relay output (self-holding relay).