Sterling 882.00379.00 User Manual

Page of 138
Conveying System Mechanical Components    Chapter 4: Operation 
80 of 138 
High Vacuum Relief Regulator Operation 
A factory-set pressure regulator is installed on the pump package vent valve as a mechanical 
back-up safety feature. It protects the pump motor from damage during high vacuum 
conditions if an undetected failure of the vacuum switch should occur. The regulator is set to 
limit system vacuum to 15” Hg (475 millibars) by allowing the vent valve plunger to shift 
and vent the pump.  SPC vacuum relief is set at lower levels based on vacuum pump 
performance curves. 
Note:  Do not adjust the pressure regulator.  Adjusting the pressure regulator voids 
your warranty. 
See Figure 36 on page 71 for additional operation information. 
4-3  Shut-down 
To deactivate the conveying system: 
1.  Turn the disconnect switch at each pump or component to OFF.  This will take each 
pump or component offline. 
2.  Turn off the compressed air supply to the system. 
Note:  Consult your specific controller operation and instruction manual for specific 
shut-down information for your conveying system.