b. With the switch still fully closed and the interrupter cocked (set to trip), the lever
should stick above the nylon bumper at least 1/8". There should be no metal-to-metal
contact between the interrupter's lever and the contactor casting. The lever should rest
in the air gap as shown below. Raise the interrupter lever and make sure the lever
clears without touching any metal.
c. Slowly open the switch and be sure that the following operations occur:
• As the blade opens, the bottom of the blade touches the auxiliary contacts before
the blade leaves the main contacts (see Figure 1 below) this transfers the load
from the main contacts to the auxiliary contacts. As the switch continues to open,
the main contacts will part and no longer carry the load, meanwhile the auxiliary
contacts will carry the full load (see Figure 2 below).
• As the blade continues to rotate open, the interrupter lever must make full metal-
to-metal contact with the contactor. At this point the load then transfers from the
auxiliary contacts to the interrupter's lever arm so that the interrupter now carries
the full load.
Figure 1 Figure 2
Phase-over-phase Vector® group-operated switches (600 and 900 A) Instruction Manual
9
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