Instruction manual

VHS-4, VHS-6 and VHS-250 Diffusion Pumps
28
D R A F T 6 / 1 8 / 1 3
1.2 Installation
Installation consists of:
❑ Section 1.2.2 “Unpacking”
❑ Section 1.2.3 “Pump Oil Installation”
❑ Section 1.2.4 “Vacuum System Connections” on page 29
❑ Section 1.2.5 “Cooling Water Connections” on page 29
❑ Section 1.2.6 “Electrical Connections” on page 30
❑ Section 1.2.7 “Thermal Switch” on page 31
1.2.2 Unpacking
When unpacking the pump:
1. Inspect the pump to ensure that no damage has occurred during shipping.
Do not discard any evidence of rough handling; report any damage to the carrier and to
Agilent without delay.
Diffusion pumps are factory-packed to permit prolonged storage in suitably protected
areas without special precautions.
2. Remove flange covers and protective plugs from water connections being careful not to
scratch the inlet and foreline flanges O-ring seal surfaces.
3. Inspect the internal jet assembly. It should be concentric and firmly seated on the
bottom of the diffusion pump and the ejector nozzle must be directly in line with the
foreline.
The location of the jet is controlled by an indexing pin located on the bottom of
the pump.
NOTE The pump requires no initial cleaning if the required vacuum
level is above 10
−
−−
− 6
Torr. For pressure below 10
− 6
Torr (1.3x10
-6
mbar), follow the cleaning procedure in Section 3.3 “Cleaning”
on page 36.
4. Charge the pump with the diffusion pump oil shipped with the pump.
1.2.3 Pump Oil Installation
The recommended oil charge for the:
❑ VHS-4 is 300 cc
❑ VHS-6 and VHS-250 is 500 cc
❑ Pour the oil is normally into the pump inlet or foreline, or remove the fill plug and
pour it into the fill and drain assembly.