SDSS Interlock Motion Interlock System Test Report
August 19, 2003
The telescope motion control interlock system was tested on July 30 - 31, 2003. The system was tested by intentionally causing a known system violation and monitoring for the correct response. The test results reference the MCP encoder values converted to fractional degrees. The following is a list of the interlock items tested and the actual trip point observed.
The following e-stop switches were tested to ensure the telescope and windbaffle Azimuth, Altitude, and Rotator amplifiers all trip off inhibiting all motions.
Altitude Motion Interlocks
Azimuth Motion Interlocks
Rotator Motion Interlocks
The azimuth, altitude, and rotator motor over temperature interlocks were unable to be tested. The over temperature interlock is a calculation internal to the PLC to determine the resistance of each motor based on the motor voltage and current values. A change in motor resistance below 2 ohms indicates an over heated motor. There was no obvious way to generate I and V values from the amplifiers to generate an over-temp trip.
The slip detection interlocks were not tested. However, we found that the slip detection system would also trip with most hard limit trips.
Each individual flat field screen was not tested to the summation point as the windscreen was not installed on the telescope. The summation output from the flat field screens was tested with the altitude motion interlock tests.
The Azimuth stow position was not verified.