  An interlock system has been designed for the Fermilab Cryo-module Test Stand
(CMTS), a test bed for the cryomodules to be used in the upcoming Linac
Coherent Light Source 2 (LCLS-II) project at SLAC. The interlock system
features 8 independent subsystems, one per superconducting RF cavity and solid
state amplifier (SSA) pair. Each system monitors several devices to detect
fault conditions such as arcing in the waveguides or quenching of the SRF
system. Additionally each system can detect fault conditions by monitoring the
RF power seen at the cavity coupler through a directional coupler. In the event
of a fault condition, each system is capable of removing RF signal to the
amplifier (via a fast RF switch) as well as turning off the SSA. Additionally,
each input signal is available for remote viewing and recording via a Fermilab
designed digitizer board and MVME 5500 processor.
