Automated loop testing enables you to verify that your HART and WirelessHART devices are connected correctly, that they are communicating with your control strategy, and that scaling has been configured correctly. Each device can have its own automated loop test. Output devices connected to a CSLS are not included in the loop test.
Automated loop testing does not require personnel in the field to manipulate the process or device to force a change in a value. An automated loop test forces values on one end of an I/O connection and compares them to an expected value on the other end. You define the path to the parameter in the module and define a set of test values for comparison.
For analog output devices, the software sets the AO block mode to auto and writes the user-configured value to the block’s SP. For analog input devices, the software puts the device in fixed output mode and sets the output value to the user-configured value.
You define the automated loop test as part of the device configuration in I/O Studio. You run the test in DeltaV Device Commissioner after the device has been autosensed, is fully configured and downloaded and has a control module that can read from and write to the device. You can enable or disable automated loop testing in the auto commissioning policy.
I/O Studio also supports automated loop test templates. The template contains general test configuration properties. Templates enable you to define the basic test properties that you want to use for multiple devices. You create a template and apply it to a device to populate some of the values for the device’s loop test.