High Side Indicator (HSI)
- Measures tool roll and inclination for every receiver for full 3-C geophone orientation
- Real time monitor read out and manual capture utility
- Automatic addition of HSI data to MIRF-6 header when recording
- Automatic calibration for optimal accuracy at various tool temperatures
X-Series digitizer (AS251 or AS272) electronics now feature a High Side Indicator (HSI) device. The HSI comprises a set of calibrated internal accelerometers within each X-series GSR and ASR digitizer module so that tool inclination and roll can be monitored downhole. When this information is collated with the well deviation listing full 3-C orientation of the geophone components can be estimated.
If you have provided a well deviation listing to the ACQ job, the HSI capture tool will interpolate the WellTrak headers alongside the HSI readout for each tool depth. This will then streamline the process for inverting the true component vector from the HSI and well deviation listing for each tool position.
Capturing an HSI Record
Each time the receivers take a real record, the HSI will be saved in the MIRF header for each MD (See latest MIRF Specification document for more details). The user can also manually capture an HSI readout for all tools when monitoring.
The HSI accuracy is affected by tool temperature. ACQ will apply a correction factor to the HSI data based on the internal digitizer temperature readout. If the calibration algorithm is applied successfully you will have an ‘OK’ in the high side indicator status column.