
Last updated 10/29/2020
29
Troubleshooting
HT should be brought up by EMG staff ONLY!!
1.
If the column vacuum crashes and HT and FEG turn off...
a.
Notify EM staff
b.
Wait for TMP rollout to recover (~7 minutes)
c.
Wait for column pressure to recover (IGP < 30) (30 - 60 minutes)
i.
Turn HT on when IGP2 < 10
d.
Manually set HT to 80 kV
e.
Click “HT” to turn on
i.
Wait till measured HT is 80 kV (~ 2 minutes)
f.
Click “Operate” to turn FEG on (~ 2 minutes)
i.
Emission should be < 10 uA; after any increase in HT wait a few minutes for
emission to recover and stabilize
g.
80 → 200 kV, 10 kV steps
i.
Free high tension = true
ii.
10,000 eV steps
iii.
Select >
iv.
At 200 kV, should read ~ 7 uA emission (under HT), FEG = 75 uA
h.
Make sure FEG is operating at 3950 V (may need to select the
↵
button to refresh it)
Содержание TF20
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