1. HV capacitor Testing

2. Capacitors under testing
Two tasks
Capacitor testing (Duke)
Capacitor preparation (Hampton)
Capacitors under testing
Johanson surface mount
1000pf, rated 2000 V, size 821.
Material : X7R
Choices are limited due to space
Capacitors from four different lots (batches).
~Two years ago, the same capacitors (from different lots) were radiation tested at CERN and the results were mixed.

3. HV testing HV cycle Results Conclusion : Pass
Connect 30 capacitors from each batch to HV=2000 V and discharge.
Measure the total capacitance every 50 discharges.
Number of cycles : 2000
Results
Batch 1
One capacitor
Surface HV breakdown during cycles
Inner HV breakdown during cycles
Batch 2/3/4 : No problem
Conclusion : Pass

4. Test setup

6. Plan
Repeat the same test with capacitors from HU (encapsulated and legs are attached)
Long term test
30 capacitors from each batch connected to HV=2000 V and current is monitored.
Irradiation test – CERN
Requirement : All capacitors from all batches should pass.
Decision by the end of There should be no problem in getting the capacitors (~6 weeks).
Radiation test on ~100 random samples once the production batch is available
Option in case of failure
Go to lesser capacitance with different material (NPO)