FEI Quanta FEG 250, User'S Operation Manual

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System Operation: Quanta FEG Vacuum System
3-2
Quanta FEG Vacuum System
Within the system there are three main vacuum sections:
• Gun
• Column
• Specimen Chamber
Both Column and Specimen Chamber sections are vented for a
sample exchange. In operation the Gun and Column sections are
always under the high vacuum. The Specimen chamber is at the
pressure required for the given mode (HiVac / LoVac / ESEM).
All valve and pump operations are fully automatic.
FIGURE 3-1 THE QUANTA FEG VACUUM SYSTEM
Legend:
ABV . . . . Auxiliary Bypass Valve
AGV . . . . Auxiliary Gas Valve
BPV . . . . . By Pass Valve
BTG . . . . BaraTron Gauge
CCG . . . . Cold Cathode Gauge
CIV . . . . . Column Isolation Valve
EBV . . . . . Environmental Backing Valve
ChEV . . . Chamber Evacuation Valve
ChIV . . . . Chamber Isolation Valve
IGP . . . . . Ion Getter Pump
NVC . . . . Needle Valve Control
PVP . . . . . Pre Vacuum Pump
SIV . . . . . Servo Isolation Valve
TMP . . . . Turbo Molecular Pump
TVV . . . . . Turbo Venting Valve
VV . . . . . . Venting Valve
WBV . . . . Water Bottle Valve