What does it mean when a point goes OLD in I/NET?

Issue

What does it mean when a point goes "OLD" in I/NET?

Product Line

TAC I/NET

Environment

I/NET

Cause

Points are labeled as old when the value is invalid or the point is no longer communicating. Here are possible reasons a point shows up as "OLD" or "old data"

1 - the SubLAN or UC device is offline or not communicating.  In this case all points on the device will show as "old data"

2 - Indirect points are flagged as "Old" anytime an update request is initiated and no response is received from the global point for 2 scan intervals.

3 - If the sensor on an input produces a number either lower than the low sensor limit or higher than the high sensor limit the point will go old.

4 - DDC control logic outputs a value out of range of the point

5 - SubLan Communication error

6 - Improper global level on sending controller

Resolution

1 - the SubLAN or UC device is offline or not communicating.  In this case all points on the device will show as "old data"

         Check to ensure the device is powered up and check physical communication.  Ensure that the device is enabled in MCU Configuration and verify that the correct device type is specified.

2 - Indirect points are flagged as "Old" anytime an update request is initiated and no response is received from the global point for 2 scan intervals.

         Check the scan intervals of the indirect point and increase it to a larger setting.  See TCON300 for details about how information requests are send between global and indirect points. A long scan interval will not translate to a delay in information being sent.  Also check the communication path between the 2 points and ensure all equipment is working properly.  For example if there is a known issue with an NPR that has global points underneath it, then all indirect points referencing those global points will frequently go old. 

3 - If the sensor on an input produces a number either lower than the low sensor limit or higher than the high sensor limit the point will go old.

         Check the sensor and determine if it is faulty.  If the value that is being sent is acceptable then increase and decrease the High and Low Sensor limits. This can also be caused by a sensor being disconnected.

4 - DDC control logic outputs a value out of range of the point

         Check all points that the DDC references and determine which is going old.  Use Failsafe commands whenever available.

5 - SubLan Communication error

         Check the physical condition of the wiring on the SubLan.  Determine if any SubLan device is faulty and interrupting communication.

6 - Improper global level on sending point

         Connect to the controller with the sending point and check it's global level. if the receiving point is on the same physical controller LAN wire you can set this to "LAN". If not, set it to "System"