Welch Vacuum 8925 Direct Drive Rotary Vane Pump - Manual (Page 3)

TABLE OF CONTENTS
SECTION PAGE
Section 01 - Installation 05
1.01 Unpacking 05
1.02 Pump Mounting 05
1.03 Pump Location / Environmental Conditions 05
1.04 Exhaust Provisions 05
1.05 Electric Power 06
1.06 Vacuum Connections 07
1.07 Vacuum Gauges 07
1.08 Vacuum Pump Oil 07
Section 02 - Pump Features & Principles of Operation 08
2.01 General Description 08
2.02 Principles of Vacuum Pump Operation 09
2.03 Effects of Continued Pressure Reduction 09
2.04 Ultimate Pressure 09
2.05 Pump Mechanism Description 09
2.06 Intake Anti-Suckback Protection 10
2.07 Pump Lubrication 10
2.08 Exhaust Filter 10
2.09 Gas Ballast Valve 10
2.10 UNIBARBTM Intake Fitting 11
Section 03 - Specifications 12
3.01 Specification Chart 12
Section 04 - Motor Power Specifications / Features 14
4.01 Motor Specifications Chart 14
4.02 Changing the voltage setting; 8907, 8912 & 8917 “A” Models 15
4.03 Changing the voltage setting; 8907, 8912 & 8917 “C” Models 15
4.04 Changing the voltage setting; 8905, 8920 & 8925 “A” Models 16
(Includes instructions to attach solenoid valve)
4.05 Other Electrical Configurations 16
4.06 Explosion Proof Pumps 16
Section 05 - Operation 17
5.01 Starting Procedure 17
5.02 High Pressure Operation 17
5.03 Shutdown Procedures 17
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