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<== Date ==> <== Thread ==>
Subject: Re: Ideas for Codeathon
From: Steve Lewis <[email protected]>
To: Bernd Schoeneburg <[email protected]>
Cc: [email protected]
Date: Mon, 16 Feb 2009 06:23:40 -0800
Title: Re: Ideas for Codeathon
At 9:03 PM +0100 2009/02/15, Bernd Schoeneburg wrote:
Hi all,
I would like to announce and discuss some ideas for base modifications. These are in detail:

3. Alarm Delay Field in all Records
Beside the alarm limits we have a "HYST" in the analog records. Why not also a "DLY" (delay). Some values are very unstable and have some noise or over-swing. So a short time over/under the limit should be allowed sometimes. Implementing this in the ioc has two advantages: 1.:It is analog to "HYST" which is a value-related hysteresis. "DLY" is a time-related hysteresis. 2.:Sending a lot of good/no-good messages to the clients could be avoided. This change is not so easy, many things must be considered.

I would call it ADLY ("alarm delay').  And I suggest you use this new field and another new one, ANUM ("alarm number"),  to implement this just the way ALH now does: do not raise an alarm unless there are ANUM excursions outside HYST in ADLY seconds.  I agree that it is good to push this functionality into the record because: (a) it reduces CA traffic; (b) keeps this vital information in the database which is the responsibility of the IOC developer, rather than with the possibly multiple instance and maintainers of ALH or other alarm clients. In particular, GUIs will now benefit.

One disadvantage: it hides the behavior of the device: how do you know whether the underlying, suppressed alarms are getting better or worse?  How would you know to adjust the hysteresis parameters?  As you say, "many things must be considered."
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Re: Ideas for Codeathon Schoeneburg, Bernd
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Ideas for Codeathon Bernd Schoeneburg
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