ISOCH Frequency Recorder
The ISOCH (derived from the term isochronous, the constant frequency mode of governing) frequency recorder is a microprocessor-based data acquisition system that has been designed specifically to perform un-attended measurement of power system frequency and governor quantities. The ISOCH continuously monitors the input frequency and initiates a recording based on various triggers. It has been designed for high resolution and accuracy and uses various trigger algorithms to automatically identify events that will be of interest to power system planners, operations specialists and station maintenance staff for use in NERC MOD-027 required verification of Models and Data for Turbine/Governor and Load Control
or Active Power/Frequency Control Functions.
Unlike other standalone frequency recorders, the ISOCH is capable of measuring four other analog quantities allowing the system to be used as a rugged, highly portable recorder for governor system tests and troubleshooting. It is also capable of generating an analog output signal proportional to frequency for use with other recording equipment or metering.
ISOCH Rear View Showing Connection Points
The ISOCH Client software provides a real-time display of frequency and other measured quantities and provides the interface for configuring the ISOCH triggering and recording.
ISOCH Client Real-Time Display
Configuration options include a single-phase power measurement and an isolated two-channel input card with offset and gain adjustments to maximize measurement resolution.