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Thermo Fisher Scientific

HT switch on fail,TAD test shown Vacuum interlock not ok


HT switch on fail, TAD test shown Vacuum interlock not ok


Krios G3i


These are possible resolutions for the issue:

  • re-connect IPB X14


These are possible causes for the issue:

  • IPB X14 loosen. vacuum ok interlock triggered


  1. HT module human safety circuit TAD test shown Vacuum interlock not ok.
  2. Check vacuum status. All vacuum value in normal range.
  3. Measure VCBT X30 output cable not loose.,24V exist. Issue not from vacuum side.
  4. Measure VGIB X11 output, cable not loose, no 24V. Issue should from blanker loop.
  5. check shutter monitor, there is no shutter and blanker active.
  6. Measure VGIB X10,cable not loose , there is no 24V.
  7. Measre MBOP_4 X12, cable tighten, there is 24V. Blanker OK signal exist.
  8. Follow blanker ok signal loop, finally found IPB X14 loose. 9: re-connect IPB X14, Vacuum ok interlock gone. HT switch on.

HT ON Interlock loop summary:

Physical :Vacuum ok interlock(VGIB x11 pin5/6, VGIB K1 output 24V) to HT tank.

Logical: VCBT X90(vacuum ok) &BSDR/MBOP/IPB(blanker ok) work together manage HT tank k1 .

Vac/Vcp readback manage VGIB K2, generate blanker allow signal to BSDR.

IPB X5, holder insert interlock to BSDR.

water and column split signal go through IPB. Manage(IPB k1) optic interlock.

HT on logical:
K1: Vacuum ok
K2:FEG SF6+HT cable
K3: Tank SF6+ Vessel temperature
K4: HT cable microswitch
K5: HT on
HT enable
Pilz loop
All above together Control Pilz relay, power on 50V DC PSUclipboard_e2312d281531a70ea20292527cdc7cf61.png



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