SIS non-secure parameter reference

Use a non-secure parameter reference to bring data from other SIS modules or DeltaV modules into an SIS module. Because these references are communicated over the local bus, do not use non-secure parameter references for safety-critical data.

When you create a non-secure parameter reference use the Parameter type field to convert the input to one of the three types allowed in a Logic Solver

• Convert to float with status

• Convert to boolean with status

• Convert to UInt32 with status

When used with a CSLS, SIS non-secure parameter references support status handling. You enable status handling through the SIS non-secure parameter reference Properties dialog. The dialog enables you to specify how the parameter reference manages bad status for communications and device (non-communication) statuses. For each type of status, you specify whether the parameter reference passes the status values, ignores the values or temporarily ignores the values based on the user-specified suppression time.

If a non-secure parameter reference obtains its value from another controller (or from a logic solver hosted in another controller), and the reference source stops sending new data, the system implements a 30-second time-out by default before the non-secure parameter reference is marked BAD. This is to help prevent issues if, for example, there is a failure in communication during a host controller switchover.

For Convert to boolean with status non-secure parameter references, you can also configure the value to True or False along with status masking.

If a non-secure parameter references is obtaining its data from another controller (or from a logic solver hosted in another controller), the system applies a 30-second timeout by default before the non-secure parameter reference is marked Bad when the reference source stops sending new data (for example, due to failure in communication during a switchover). This times out the chance of problems when the host controller switches over.

The path to the control module must begin with a control module tag. The control module reference is a read-only input parameter for an SIS module. Create one by dragging the non-secure parameter reference icon from the Special Items palette.