Abstract: A metering device may be configured to communicate with other devices in an advanced metering infrastructure (AMI) system. For example, a metering device may be configured to communicate with a collection device. To enable such communications, a collection device may send a wake-up-tone and/or a request message to a metering device. Based on the request message, a metering device may send data to the collection device. Metering communication networks may be mobile and/or fixed. For example, a mobile collection device may use a wireless signal to interrogate a metering device to retrieve data from the metering device.

Abstract: A metering device may be configured to communicate with other devices in an advanced metering infrastructure (AMI) system. For example, a metering device may be configured to communicate with a collection device. To enable such communications, a collection device may send a wake-up-tone and/or a request message to a metering device. Based on the request message, a metering device may send data to the collection device. Metering communication networks may be mobile and/or fixed. For example, a mobile collection device may use a wireless signal to interrogate a metering device to retrieve data from the metering device.

Abstract: A field bus network of input and output devices is coupled to a control system through an I/O interface module, regardless of their data structures. The I/O interface module is coupled to the control systemthrough a serial communication port. Local input and output devices are coupled to the interface I/O module through a local I/O interface and networked input and output devices are coupled to the interface I/O module through a field bus communication adapter. A different adapter is required for each type of field bus protocol. The interface I/O module includes a microprocessor based device to generate and control the various interactions between the local devices, networked devices, and the controllsystem and also to provide for a visual and status display of the fieldbus and local I/O data local.

Abstract: A weld controller maintains an internal dynamic model of load impedance, which tracks normal impedance variations that occur as the weld tooling degrades. The weld controller contains a weld process monitor function that tests an estimated load impedance of a weld schedule presently under execution against an internal dynamic model and generates events when characteristics of the estimated load impedance of the present weld falls outside an operator definable band, indicating a problem with the workpiece presently being welded. The weld controller further includes the capability to accept a static model of the load impedance that is used as the reference impedance for the weld control and tooling. The weld controller also includes means to declare an event when characteristics of the dynamic model differ from the static model by an operator-defined amount.

Abstract: A phase controlled weld controller system uses an internal model of weld line and load impedance and of open circuit weld input voltage to develop a nominal firing angle sequence to maintain a desired weld current sequence. The weld controller computes a nominal firing angle sequence based on estimated models of line impedance, open circuit line voltage, and an estimated relation between the load current and conduction angle and the mathematical relation between firing angle, conduction angle and load circuit power that will achieve a desired weld sequence if the models are accurate. The weld controller subsequently uses measured values received in real time while the weld sequence is being executed to modify the nominal firing angle to better achieve the desired objective. This approach allows the weld controller to quickly achieve the desired weld sequence with the actual load, while permitting low feedback gains, resulting in a system that is quick and accurate in response without being overly sensitive.

Abstract: A phase control system has a stable timebase phase reference generated by an internal phase reference generator. The control includes a method for estimating and compensating phase distortion when an inductive load is driven by an AC voltage source having significant line impedance. A digital phase comparator estimates a phase error between the timebase phase reference and the voltage source. At the initialization of the phase control system, the phase reference clock period is frozen for a fixed number of cycles to determine an average phase error due to the phase distortion caused by the line impedance. The estimated phase error is then corrected to account for the average phase distortion error.

Abstract: A phase controlled weld controller system provides a stable timebase phase reference which has improved transient response in the presence of spurious noise generated by other external equipment coupled to the same voltage source. The system estimates a phase error between an internal phase reference generator and the voltage source. The system also estimates the phase distortion generated by the weld control when operating with an inductive impedance load when significant line impedance is present. The weld controller provides compensation for the phase distortion in the timebase phase reference using the estimated line impedance to realize a phase reference which more accurately tracks the voltage source.

Abstract: A phase control system has a stable timebase phase reference generated by an internal phase reference generator which has improved transient response in the presence of spurious noise generated by other external equipment coupled to the same voltage source. A digital phase comparator estimates a phase error between the timebase phase reference and the voltage source. The internal phase reference generator constructs the timebase using a normalized difference between the volt-time-areas between two adjacent quadrants of the internal timebase phase reference. This allows corrections to the phase reference generator to be made on the next cycle of the phase reference generator based on the error estimate of the present cycle.