1. Interfacing the FMCM for additional protection in the LHC and the SPS- LHC/CNGS Transfer Lines to the CERN controls system Cristina Gabriel Casado, Interlock Team AB/CO CERN, European Organization for Nuclear Research, Geneva, Switzerland 4th August 2005 Conclusions A prototype board for the conversion of data provided in TTL levels to an RS232/RS422 standard has been developed, built and tested using the serial communication to a standard desktop PC. A developed visual basic application allows for the visualization of the received data and for sending of commands to the FMCM device. Based on this first tool, the protocol for data transfer between the FMCM and the VME processor (using the FESA framework) will be developed.. Further improvements will be applied to achieve the final version of the hardware and software, to be ready for beam commissioning in the SPS-LHC/CNGS transfer lines in the mid of 2006. Abstract The protection of the electrical system for the Large Hadron Collider (LHC) currently being built at CERN is a major challenge due to the unprecedented complexity of the accelerator. Fast Magnet Current Change Monitors (FMCM) will be deployed in the LHC and the SPS-LHC-CNGS transfer lines. The monitors interface directly to the beam interlock systems of the LHC and the SPS-LHC-CNGS transfer lines and issues beam dump requests or inhibits extraction in case of powering failures that would have fast effects on the particle beam(s). A prototype for a connection of the FMCM to the CERN controls system for remote interaction and post mortem readout has been developed and is presented here. What is it doing? Detection of powering failures in critical electrical circuits and to provide a permit signal to the beam interlock system in the transfer lines or the LHC Why? The FMCM has the advantage of detecting powering failures even before the beams start to move or beam losses occur. How does it work? The magnet/circuit voltage is measured Making a real time calculation of the magnet current Filtering for fast current changes Comparison with a pre-defined tolerance window If they exceed the threshold an alarm is issued The alarm triggers a beam dump request towards the BIC Creation of a post mortem record for later event analysis PROTOTYPE BUILD HARDWARE  TTL/RS232/RS422 converter board SOFTWARE  protocol TEST 81162 synchronizationstartcodeargumentchecksum tPrepare update of timestamp dDump sRead status pRead post mortem data rReset alarm and/or pre-alarm counter iIdle 2032 headerstatus 204000 headerPost mortem data COMMANDS RESPONSE (bytes) In its final configuration, the FMCM is connected via a serial RS422 interface to the VME front end computer and the CERN controls system Main characteristics RS422 38400 to 115200 bauds Start bit+8 bits data+1 bit odd parity+stop bit Full duplex For the time being, test are done using the RS232 interface to a standard PC and a Visual Basic 6 application TI2, TI8, CNGS, TT41 Septas (MSE, MSI, MST) MBB, MBG MBI, MBHC MBIBH LHC D1 in IR1 and IR5 Dump septa in IR6 Maybe IR3, IR7 for combined failures