Deviation Value

(DEVIATION_VAL)

The user provides the maximum engineering units threshold. On each update, the system will calculate the engineering units change from the previous value and set the alarm bit if the engineering units change exceeds the threshold.

Digital Value Equal

(DIGITAL_EQUAL)

The user selects the state for alarm. On each update, if the value matches this state, then the alarm bit is set, otherwise it is cleared.

Maximum Value

(MAX_VALUE)

The user provides the maximum value threshold for the alarm limit. On each update, the system will check the value and set the alarm bit if it is more than the allowed threshold. This calculation type is used for High Alarm and High Warning.

Minimum Value

(MIN_VALUE)

The user provides the minimum value threshold for the alarm limit. On each update, the system will check the value and set the alarm bit if it is less than the allowed minimum. This calculation type is used for Low Warning and Low Alarm.

String Filter (case-insensitive)

(STRING_VAL_CI)

The user provides a string to compare against. This supports wildcards. On each update, if the new value matches the comparison string without regards to case, the alarm bit is set, otherwise it is cleared.

String Filter (case-sensitive)

(STRING_VAL_CS)

The user provides a string to compare against. This supports wildcards. On each update, if the new value matches the comparison string with regards to case, the alarm bit is set, otherwise it is cleared.

Change Rate

(CHANGE_RATE)

The user provides the maximum allowed number of changes and the time interval. On each update, if the point value changes more than the maximum allowed times for a given interval, the system will set the alarm bit. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. This will be used for Digital Chattering alarms, for one example. See Change Rate Alarm Calculation.

Change Value

(CHANGE_VAL)

On each update, the system will set the alarm bit if the point’s value is changed. It is cleared every time a point is updated with the same value. See Change Value Alarm Calculations.

Change Value Negative Percent

(CHANGE_VAL_NEG_PCT)

The user provides the maximum percentage threshold and the time interval in seconds. On each update, the system will calculate the percentage change between the new value and the newest value older than the time interval, divided by the time interval in seconds, and set the alarm bit if the percentage change is negative and exceeds the threshold. Note that the threshold must still be represented as a positive percentage. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Change Value Alarm Calculations.

Change Value Percent

(CHANGE_VAL_PCT)

The user provides the maximum percentage threshold and the time interval in seconds. On each update, the system will calculate the percentage change between the new value and the newest value older than the time interval, divided by the time interval in seconds, and set the alarm bit if the absolute value of the percentage change exceeds the threshold. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Change Value Alarm Calculations.

Change Value Positive Percent

(CHANGE_VAL_POS_PCT)

The user provides the maximum percentage threshold and the time interval in seconds. On each update, the system will calculate the percentage change between the new value and the newest value older than the time interval, divided by the time interval in seconds, and set the alarm bit if the percentage change is positive and exceeds the threshold. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Change Value Alarm Calculations.

Creep Average

(CREEP_AVG)

The user provides the maximum engineering units threshold, as well as the time interval. On each update, the system will calculate the average from the newest value older than the time interval to (and including) the previous value. The system compares the difference between the average and the update value, and sets the alarm bit if the difference is more than the threshold. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Creep Alarm Calculations.

Creep Value

(CREEP_VAL)

The user provides the maximum engineering units threshold, as well as the time interval. On each update, the system will calculate the engineering units change from the newest value older than the time interval, and set the alarm bit if the change exceeds the threshold. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Creep Alarm Calculations.

Delta Over Time Positive

(DELTA_OVER_TIME_POS )

The following parameters are configurable on a point-by-point basis: the delta and the time interval (in seconds). Together these define the rate-of-change. On each update, the CVS will find the first value that is older than the time interval specified, and then:

• the system calculates the value and time deltas between those two values and then gets the rate from those two values.
• if the rate exceeds the configured rate, the alarm is set, otherwise it is reset.

The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Delta Over Time Alarm Calculations.

Delta Over Time Negative

(DELTA_OVER_TIME_NEG)

The following parameters are configurable on a point-by-point basis: the delta and the time interval (in seconds). Together these define the rate-of-change. On each update, the CVS will find the first value that is older than the time interval specified, and then:

• the system calculates the value and time deltas between those two values and then gets the rate from those two values.
• if the rate is less than the configured rate, the alarm is set, otherwise it is reset.

The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Delta Over Time Alarm Calculations.

Deviation Percent

(DEVIATION_PCT)

The user provides the maximum percentage threshold. On each update, the system will calculate the percent change from the previous value and set the alarm bit if the percent change exceeds the threshold. See Deviation Alarm Calculations.

Duration Alarm

(TIMED_ALARMSTATE)

The user provides the list of CVS configurable alarm bits to monitor and the time interval. Whenever the time interval is reached, the system will find the first time all of the listed CVS configurable alarm bits were all set. If that time is before the time interval, the alarm bit will be set. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Duration Alarm Calculation.

Frozen Percent

(FROZE_PCT)

The user provides the minimum percentage threshold, as well as the time interval. Whenever the time interval is reached, the system will calculate the percentage change from the newest value older than the time interval and set the alarm bit if the percentage change is less than the threshold. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. See Frozen Alarm Calculations.

Frozen Value

(FROZE_VAL)

The user provides the time interval. Whenever the time interval is reached, the system will set the alarm bit if the point’s value has not changed in this time period. It is cleared every time a point is updated with a different value. The time interval is relative to the time that the CVS received the point value, not relative to the time of the point value’s timestamp. That is, if the value is posted in the past or in the future, it can still get marked as frozen. See Frozen Alarm Calculations.

Frozen Value with Delay

(FROZE_VAL_DELAY)

The user provides the minimum engineering units threshold, as well as the time interval. Whenever the time interval is reached, the system will calculate the change in engineering units from the newest value older than the time interval and set the alarm bit if the change is less than the threshold. The system will provide a maximum of 60 entries to store for this calculation. If more than 60 values come in within the time frame specified, the alarm will never be triggered. An engineering unit of 1 and a time interval of 00:01:00 means the value must change by at least 1 engineering unit from the value of 1 hour ago. See Frozen Alarm Calculations.

Out-of-Range Enumeration

(OOR_ENUM)

The user provides an update option of Update Value, Leave Value, or Retain Old Value. On each update, if the setpoint value is not in the enumeration table, the following updates take place:

1. If the update option Update Value is selected and a table entry of _OOR_ is found in the enumeration table, the point value is updated to the table entry for _OOR_.
2. If _OOR_ is not found, or if the update option is Leave Value, then the point value is left unchanged.
3. If the Update Option is Retain Old Value, the new value will be changed to the old value presently in the CVS. If the calculation type is enabled, the bit will be set if the setpoint value is not in the enumeration table, otherwise, it is cleared.

All Bits Set From List

(ALL_BITS)

The user provides a list of CVS status bits by name in the reference bits for the calculation type. If all of the provided status bits are set in the Base Status or Extended Status bits, the alarm bit is set, otherwise it is cleared. The bits are listed in the CvsMetadata.xml file. See Bit(s) Set From List Alarm Calculations.

Any Bit Set From List

(ANY_BIT)

The user provides a list of CVS status bits by name in the reference bits for the calculation type. If any of the provided status bits are set in the Base Status or Extended Status bits, the alarm bit is set, otherwise it is cleared. The bits are listed in the CvsMetadata.xml file. See Bit(s) Set From List Alarm Calculations.

Not All Bits Set From List

(NOT_ALL_BITS)

The user provides a list of CVS status bits by name in the reference bits for the calculation type. If not all of the provided status bits are set in the Base Status or Extended Status bits, the alarm bit is set, otherwise it is cleared. The bits are listed in the CvsMetadata.xml file. See Bit(s) Set From List Alarm Calculations.

All PNT Y/N Fields Set From List

(ALL_PNT)

The user provides a list of PNT Boolean attributes by name in the reference bits for the calculation type. If all of the provided Boolean attributes are set on the PNT record, the alarm bit is set, otherwise it is cleared. See PNT Y/N Field(s) Set From List Alarm Calculations.

Any PNT Y/N Field Set From List

(ANY_PNT)

The user provides a list of PNT Boolean attributes by name in the reference bits for the calculation type. If any of the provided Boolean attributes are set on the PNT record, the alarm bit is set, otherwise it is cleared. See PNT Y/N Field(s) Set From List Alarm Calculations.