FC 99 - Sequence of Events Log

This block enables a module to communicate with a sequential events recorder (SER). The sequence of events (SOE) log buffers event data received from the SER recorder for human system interface (HSI) access. Five types of SOE logs can be generated: standard, summary, prefault, postfault and snapshot. Each SOE log holds only one type of report, and the report

includes data on all points configured in the SER recorder to be that type. Each block is independent and relies only on a common serial link to acquire event data. The SOE log function code specifies buffer size and the age of the event data in the buffer. Configure a single block for each log type, buffer size and age.

 

NOTE: This function code is supported only on the BRC-100 and the IMMFP11/12 controllers.

 

The sequence of events log sets local I/O module status to bad and generates a module problem report when the sequence of events recorder global I/O status is bad (i.e., input check failure). Output block N remains good quality on this failure.

 

Outputs:

Blk

Type

Description

N

B

Events logged flag:

0 = no

1 = yes

 

 

Specifications:

Spec

Tune

Default

Type

Range

Description

S1

N

0

I

0 - 4

Qualifier for sequence of events recorder data received buffer storage:

0 = standard

1 = summary

2 = prefault

3 = postfault

4 = snapshot

S2

N

256

I

0 - 3,500

Number of events that fit in buffer: buffer size = 9(S2+1)

S3

N

360

I

0 - 32,767

Age of event data (in secs) before discarded from buffer

 

 

99.1 Explanation

 

Function code 99 provides a communication link between the SER recorder and an interface device such as a console or computer. Data cannot be sent directly from the recorder to interface devices. The interface must be configured to print the event data received from the module. See the operators manual for the interface device to determine how to configure it to receive sequence of events data. Each sequence of events log in the module has an associated sequence of events configuration in the interface device. The sequence of events log is an exception report block with the same report type and size as a remote control memory (function code 62) exception report. The remote control memory command from the interface device requests a summary report.

 

NOTE: Dedicate the module used for sequence of events reporting to SER functions only. It cannot be configured for redundancy, BASIC, C language, batch or user defined functions.

 

The SER recorder is capable of handling up to 512 I/O points. The SER recorder defines point report types for all points. There are five report types available (standard, summary, prefault, postfault and snapshot).

 

 

 

99.1.1 Specifications

 

S1 - LOG TYPE

Qualifier for SER recorder event data buffer storage.

0 = standard

1 = summary

2 = prefault

3 = postfault

4 = snapshot

 

Standard

The standard type reports any standard SER recorder point change of state. Changes from normal-to-alarm or from alarm to-normal result in a time-tagged report generated for that point. The results are stored in the module for the length of time specified by S3.

 

Summary

The summary report is generated on an operator demand from the interface device. This is a time-tagged report listing all SER recorder points that are not normal (i.e., inactive, deleted from scan, or in alarm). A remote control memory display type should be configured in the interface device to force the output of this function code to a one to request this summary data collection.

 

Prefault

The prefault mode stores the points when they change state. Up to 1,000 predefined events and a specified time window (up to 24 hours) limit the data stored. For example, this report can be configured to list the last 50 events prior to the prefault trigger, or all events occurring up to ten minutes before the prefault trigger. The trigger is a false to true signal resulting from an event or a series of events. When the trigger occurs, all of the stored data reports, with the oldest stored data reported first. The memory then begins saving new data. The new data will not be reported until the trigger outputs a false to true signal again.

 

Postfault

The postfault mode reports points when they change state, but only after the postfault trigger turns true. These points will be reported until the postfault trigger turns false, or the operator cancels the postfault state.

 

Snapshot

Snapshot inputs are typically a group of related points. These points, like any point in the system, can be in the alarm, normal, deleted, or inactive state at any one time. When the snapshot trigger turns true, a report generates detailing the status of the designated snapshot points in numerical point order. Another report generates the next time the snapshot

trigger outputs a false to true signal.

All points defined in the SER recorder as a certain type will be saved in the buffer of the sequence of events log defined as the same type. For example, if this log is a standard log (zero), all points defined in the SER recorder as standard are sent to this buffer.

 

S2 - EVENT NO.

Number of events that fit in the buffer. Each log has a separate buffer that holds a specific number of point values. The buffer is in RAM memory, and the buffer size determines RAM memory utilization.

 

buffer size = 9(S2 + 1)

 

 

S3 - AGE

Maximum age in seconds of the event data in the buffer. After data has been in the buffer for this length of time, it is removed from the buffer. The buffer age is reset to zero every time an event for the specified log occurs.

 

A new and unique buffer age time is attached to each event saved in the buffer. Older events are therefore removed from the buffer before newer events when their buffer age time expires. Any data stored in the buffer is guaranteed to stay in the buffer for the configured age time.

 

Specifications S2 and S3 are closely related to the interface device configuration. These parameters control the amount of data the interface device can receive when a trip occurs. The interface device must be configured to provide a fast enoughdata transfer rate to remove the event data from the buffer before S3 is reached. Once S3 is reached, the data is erased.

 

99.1.2 Outputs

 

N

Events logged flag.

0 = no

1 = yes

 

Output N shows whether the buffer currently contains data received from the SER recorder. The output goes to one every time information is fed to the block from the SER recorder, and returns to zero when all the data has aged (S3) and is erased.

If multiple or oscillating events occur, the new data is saved in the buffer with a new age time (S3). Then, the output remains a one until all new data in the buffer is aged. If new data continues to filter in at a period less than S3, the output never goes to zero.

NOTE: A console report will not print until this output goes to zero.