Fri, 11.11.2022 23:12:37 BR: GTPC drift HV supply did not show current increasing linearly with voltage. Current would stay at 0A until ~8 kV, and then increase to ~10uA.
Debug checks:
-Resistance at power supply end of HV cable: 40 MOhm. Check.
-Output of power supply at chamber end: 0.5 kV, matching power supply monitor. Check.
-Current flow through 1 MOhm resistor measured with HV supply: 0.5 mA at 500V. Check.
-Unplugged cable at chamber: sparks at ~8 kV.
After sparking 3 times, the system works. At 10 kV drift HV supply, the current monitor wiggles a bit. Something is probably discharging.
Piotr proposes taking Krypton calibration data with 8 kV drift field. This should not affect chamber gain, as far as we can think. |