Attribute tab PI Template Row Edit

Point attributes owner

Enter the user name to be assigned to own the point attributes. This can be the same as the Data owner and by default is the creator of the point.

Group point attribute owner

Enter the group name to be assigned to own the point attributes.

Point Read/Write Access

Enter the point attribute access permissions for owner, group, and world. For example: o:rw g:r w: (owner can write and everyone can read.)

Data owner

Enter the user name to be assigned to own the data. This can be the same of the Point attributes owner and by default is the creator of the point.

Group data owner

Enter the group name to be assigned to own the data.

Data Read/Write Access

Enter the data access permissions for owner, group, and world. For example: o:rw g:r w: (owner can write and everyone can read.)

Enable compression

A Boolean value: Select checkbox (1) to enable compression or clear checkbox (2) to disable compression.

Compression deviation value

An event is archived in two circumstances:

• If the elapsed time since the previous event is greater or equal to the Compression time minimum and the value has changed by more than the Compression deviation value.

• If the elapsed time is greater than the Compression time maximum. (It is recommended to set compmax to one work shift [for example, 8 hours].)

  Note: Compdev specifies the compression deviation in engineering units.

Compression time maximum

Compression time minimum

Exception deviation amount

An exception is sent in two circumstances:

• If an event occurs and the time since the last event is greater or equal to the Exception minimum time and the value has changed more than the Exception deviation amount.

• If an event occurs and the elapsed time is greater than the Exception maximum time.

  Notes: The Exception deviation amount should be less than the Compression deviation amount by at least a factor of 2.

  Excdev specifies the exception deviation in engineering units.

Exception time maximum

Exception time minimum

Enable archiving

A Boolean value: Select checkbox (1) to enable archiving or clear checkbox (2) to disable archiving.

Step interpolation

A Boolean value: Select checkbox (1) to treat archived values discretely; an archived value is assumed constant until the next archived value. Clear checkbox (2) to treat archived values as a continuous signal; adjacent archived values are linearly interpolated. For example:

• At 12:00:00, the value 101.0 is archived.

• At 12:01:00, the value 102.0 is archived.

  If stepflag is on a request for the archive value at 12:00:30 would return 101.5. If stepflag is off a similar request would return a value of 101.0.

Note: Stepflag also affects the compression calculation. When on, a linear change of value greater or equal to compdev passes compression. When off, the complete swinging-door algorithm is applied.