Figure 1 General view
1. NW40 inlet port
2. Gas ballast control
3. Cooling fan
4. NW25 exhaust port
5. Fan connector
6. Rubber feet
7. Electric connector
8. Voltage changeover switch cover
9. Run/Standby switch
10. 15
‑
way connector
11. Hour counter
12. Lifting eye
1. NW40 inlet port
2. Gas ballast control
3. Cooling fan
4. NW25 exhaust port
5. Fan connector
6. Rubber feet
7. Electric connector
8. Voltage changeover switch cover
9. Run/Standby switch
10. 15
‑
way connector
11. Hour counter
12. Lifting eye
2.3 Description
Refer to
Figure: General view on page 9
for item numbers in brackets in the following
descriptions.
The XDS pump is a compact, reliable vacuum pump which is suitable for use on vapour
handling processes. It may be used for some pumping applications involving corrosive
substances and particulates; for information on pumping flammable gases, please refer
to
Implication of ATEX directive on page 22
and contact us for any further assistance.
The body of the pump includes a fixed scroll and an orbiting scroll. The orbiting scroll is
controlled by the electric motor through an eccentric cam on the motor drive shaft. The
movement of the orbiting scroll, meshed with the fixed scroll, forms successive crescent
shaped volumes in the pump. Gas that enters the pump through the inlet is compressed
by the movement of the orbiting scroll and swept towards the centre of the fixed scroll.
The compressed gas enters the exhaust port near the centre of the stationary scroll and
is exhausted from the pump through the outlet.
The XDS is a dry vacuum pump, as all the bearings, with hydrocarbon lubricant, are
isolated from the vacuum space. The pump has an NW40 (item 1) inlet and inlet strainer.
The pump mechanism is driven directly by a three-phase electric motor. The motor is
Page 9
A73101880_F - Introduction