The error bit can be set on any of the points that the Line Pack driver outputs to on a pack segment. It will be set under any of the following conditions:

• Set on output points if there is an error in the calculation. An error will occur if:

• No valid value is available for at least one of the inputs.
• The supercompressibility calculation returned an error because an input was out of range.

• For any inputs that cause a calculation error (as specified above), the associated input used UDC set on the pack segment will have the error bit set.

Set on any points used as an input to the Line Pack calculation. For example, if a user specifies the tag “SAMPLE.UIS::POINT1” for the Upstream Pressure input in a rule which is used, then the bit will be set on the point SAMPLE.UIS::POINT1.

Set on a pack segment if one of its default or base inputs were used for the calculation.

Set on any value that Line Pack sets. This indicates that the value (and timestamp) was set by the Line Pack driver, for whatever reason.

This bit can be set on any of the points that the Line Pack driver outputs to on a pack segment. It will be set under any of the following conditions:

• Set on output points if any inputs used are deemed unreliable. An input is unreliable if:

• The point used already had the unreliable bit set.
• The value of an input was out of range, as determined by the minimum and maximum settings for the input in the Line Pack editor.
• The value of the input is non-numeric and doesn’t resolve to a valid CygNet point.
• The tag specified for an input has units that are unconvertible to the required units.
• The tag specified for an input has no units for an input that does have unit requirements.

• For any inputs that were deemed unreliable (as specified above), the associated input used UDC set on the pack segment will have the unreliable bit set. For example, if the Last Segment Input: Inlet Press was deemed unreliable, then the Input used - Upstream Pressure would have the bit set.