Newport IPV, Руководство по установке

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4. When the table is completely level, ensure by eye that every isolator
support plate is snug against the table bottom and that each centering
disk is centered in its guide (Figure 4).
5. Use the level to confirm that the table top is still level and equally
supported by all isolator support plates. Tighten all isolator clamp bolts
snugly to secure the table to the isolators.
6. Loosen the two screws securing each leveling valve to its bracket. Slide
the valve body until it is approximately 0.060 inches (1.5mm) below the
bottom of the table. Be sure the valve is not tilted, then tighten the
screws (Figure 6).
2.3 Isolating the Table Top
2.3.1 Installing Leveling Valves
The IPV leveling valve is shown in Figure 5. Three valves are used in all
systems, regardless of the number of isolators, as only three points are
required to determine a plane. The leveling valve locations are selected such
that they form the largest triangle possible under the table. The larger the
triangle, the more stable the system will be. When two or more isolators are
controlled by the same valve, they act as a single large isolator supporting the
table at the center of force of the several isolators. The floating height of the
system is determined at the valve position. Therefore, ideally, the valves
should be located at the center of force of the isolators they control. In
practice, however, simply grouping the isolators and their control valves is
sufficient. The groups of isolators and their valves act as three legs for the
system. The center of gravity of the combined table and payload must be
within the triangle formed by the centers of force of the isolator groups for
the system to float. Figure 8 shows valve and isolator arrangements for
rectangular tables. Complex table shapes require isolator and valve layouts
designed specifically for each application.