User`s guide

Page 86

Controlinc 1746-C (Version 5.21) Network Master Users Guide (2004-11-18)

5.4.18. Tables [21-24]: TEC2000 Status Inputs

Words [4  63] PLC access: Read / Write

The purpose of these tables is to afford the end user all critical status information from TEC2000

systems. TEC2000 systems are backwards compatible with the 320A/B systems. However, there

are more “things that can be checked” in the TEC2000. For instance, in the TEC2000, the Unit Alarm

is also tripped by a “Valve Drift” Alarm. The “Valve Drift” alarm is not available in the 320A/B systems.

Therefore: For maximum compatibility with the TEC2000 systems, it is recommended that you

enable monitoring the TEC2000 Status Inputs (tables [21-24]). This way, you can ensure you

have all critical status information for any TEC2000 system on the network.

This data is derived from holding registers [1000 - 1003] in the TEC2000 actuator. These table

entries are only filled in if

• The particular valve is a TEC2000 system.

• The 1746-C is configured to poll these additional registers.

This data is retrieved with a separate Modbus read command when the particular actuator is being

polled (scanned).

These tables are not polled for unless the 1746-C is configured to allow it …

• if Table [0] – Word [17] == 0: The TEC2000 status input information is NOT requested when

actuators are polled (

the default).

• if Table [0] – Word [17] =/= 0: The TEC2000 status input information is requested when

actuators are polled.

The PLC may reset these tables with any value is prefers. All it needs to do is insert the new value in

the table and send it to the 1746-C as a write command. The table will be reset even though nothing

will be sent out to any actuator.

A read back of Tables [21 - 24] will

• If a write command issued: reflect the table write command accepted by the 1746-C

• If a read command issued: reflect the last known values of the status input registers in the

TED2000 actuators.