Coude Azimuth Display

Owned by Tim Williams
Last updated: Dec 26, 2024 by Karl Newman
2 min read

 

This display is divided into two main sections, the GIC related indicators and the local Coude indicators.

GIC indicators

The GIC indicators include the ‘big three’ interlocks that come from the GIC: E-Stop, Seismic Alarm, and Fire Alarm. If any of these are not OK no motion of the Coude Rotator is possible.

Next there are indicators for the status of the Trapped Keys associated with Coude Rotator. These will either prevent or speed limit the motion of the Coude Rotator if they are not in place.

Same with the indicators for the various doors associated with Coude Rotator.

Coude indicators

Coude Emergency Stop

This indicates the status of the Emergency Stop devices associated with the Coude Axis. The indicator also functions as a GOTO button that will open the Coude E-Stop Display.

Cabinet Environmental

This indicates if there is an issue with cooling in any of the drive or electronic cabinets that are part of the Coude Motion Control System.

Cable Wrap Alignment

This indicates if there is a misalignment between the Coude Rotator and cable chain.

Azimuth Hard Stops

The hard stops are part of the final limit function of the Coude Azimuth rotation. During most of the range of motion of the Coude Azimuth the hard stops are in the undeployed ‘down’ state. As the axis nears the end of travel the hard stops will deploy (pop up) to stop the axis from exceeding the mechanical limits of the system.

The final limits should activate prior to the mechanical limit being reached but the hard stops function as a mechanical backup.

The hard stops are monitored in three zones. The non-deploy zone where the hard stops must be in the non-deployed (down) state. Then there are the two deploy zones, lower end and upper end, in which the hard stops must be deployed (up).

The safety function monitors this and will stop the Coude Rotator if the hard stops are not in the correct position.

Azimuth Final Limits

The Coude Azimuth final limits monitor the position of the Coude Rotator to ensure it does not exceed mechanical limits.

If the Coude Azimuth has exceeded the allowable final limits the Rotator must be manually moved out of the final limit. Connect an HHD and manually drive the rotator out of the limit while visually monitoring the motion.

Azimuth Speed Limit

The Coude Azimuth rotation speed is monitored for three conditions:

  • below maximum speed

  • below safely limited speed

  • Safe Stop deceleration curve monitoring

If any of the limits are exceeded the Coude Rotator will stop.

Reset requires that the associated Kuebler encoder be reset.

Azimuth Stop Ramp

Cabinet Doors Closed

The various cabinets on the Coude Rotator are monitored to ensure they are closed during Coude Rotator movement.