  A quench detection system was developed for protecting and monitoring the
superconducting solenoids for the Muon-to-Electron Conversion Experiment (Mu2e)
at Fermilab. The quench system was designed for a high level of dependability
and long-term continuous operation. It is based on three tiers: Tier-I,
FPGA-based Digital Quench Detection (DQD); Tier-II, Analog Quench Detection
(AQD); and Tier-3, the quench controls and data management system. The Tier-I
and Tier-II are completely independent and fully redundant systems. The Tier-3
system is based on National Instruments (NI) C-RIO and provides the user
interface for quench controls and data management. It is independent from Tiers
I & II. The DQD provides both quench detection and quench characterization
(monitoring) capability. Both DQD and AQD have built-in high voltage isolation
and user programmable gains and attenuations. The DQD and AQD also includes
user configured current dependent thresholding and validation times.
  A 1st article of the three-tier system was fully implemented on the new
Fermilab magnet test stand for the HL-LHC Accelerator Up-grade Project (AUP).
It successfully provided quench protection and monitoring (QPM) for a cold
superconducting bus test in November 2020. The Mu2e quench detection design has
since been implemented for production testing of the AUP magnets. A detailed
description of the system along with results from the AUP superconducting bus
test will be presented.
