Edwards nRVi, Instruction Manual

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2. General description
2.1 Overview
The nRVi rotary vane pump is a two-stage, oil-sealed, sliding vane vacuum pump. The
pumping mechanism is driven by a three phase motor with power taken from a single
phase supply via the pump controller.
Refer to
Figure: General view of the pump on page 12 for item numbers in brackets in
the following descriptions.
The pump has NW25 inlet and outlet ports, a gas ballast control and a mode selector.
When the pump is switched off, an inlet valve seals the inlet and prevents the suck back
of air and oil into the vacuum system.
All nRVi pump variants are fitted with a lifting bracket for use with suitable lifting
equipment.
An oil pump delivers pressurised oil to the vacuum pumping mechanism in the pump.
The oil level and condition can be inspected in the oil box through a sight glass. Two oil
filler plugs and an oil drain plug are provided on the oil box.
The pump mechanism is driven directly by an electric driver and electric motor and
through a flexible motor coupling. The motor is totally enclosed and is cooled by the
motor cooling fan which directs air along the motor fins. The pumps are cooled by an
additional fan attached to the motor coupling.
The pump is mounted on a base plate on rubber feet. Details of suitable vibration
isolators and other accessories are provided in Accessories on page 86 .
Refer to PFPE-prepared rotary vane pumps on page 90 for additional information if the
pump is PFPE-prepared.
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A65901880_D - General description