IviPwrMeterBase Behavior Model

The following state diagram shows relationships between the IviPwrMeterBase capability group and power meter behavior.

The main state in the IviPwrMeter Class is the Idle state. The power meter enters the Idle state as the result of being "powered-on", successfully completing a measurement, or by being aborted from a previous measurement by you with the Abort VI. Typically, you configure the power meter while it is in the Idle state. IviPwrMeter attributes can be configured individually by setting properties or with the high-level configuration VIs defined in the IviPwrMeterBase capability group.

The Read and Initiate VIs cause the power meter to leave the Idle state and take a measurement on all enabled channels. The Read VI does not return until the measurement process is complete and the power meter has returned to the Idle state. The Initiate VI returns as soon as the power meter leaves the Idle state. The Fetch VI is used to retrieve measurements that were initiated by the Initiate VI.

As soon as the power meter leaves the Idle state, it immediately takes a measurement on all enabled channels. You enable channels by calling the Configure Measurement VI before initiating the measurement. The power meter takes a measurement on the channels specified in the Configure Measurement VI and performs the specified math operation on the results.

After all measurements have been taken, the power meter (if it is capable of doing so) generates the Measurement Complete signal and returns to the Idle state. The IviPwrMeterBase capability group does not require that a power meter be able to generate a Measurement Complete signal. The IviPwrMeterBase capability group does not define how a Measurement Complete signal is configured. The Measurement Complete signal is presented in the IviPwrMeter behavior model diagram to define when the signal is generated as most power meters generate this signal but may not be able to configure it.