Sterling 882.00379.00 manual Start-up, Operation Procedures, Vacuum Switch VS Operation

Chapter 4: Operation

4-1 Start-up

Starting ACA Series Filter Chamber Units

Turn on clean, dry, oil-free compressed air and regulate to 60 psi to 80 psi (414 kPa to 552 kPa). Turn the power on/off switch to ON; the unit then automatically self-cleans the filter bags. An indicator light on the control box for Model 91/93, 151/153, and 251/253 ACA filter chambers illuminates each time a compressed air pulse is directed into a filter bag.

Note: If for any reason the power is turned off, wait at least three (3) seconds to reset.

4-2 Operation Procedures

When you activate the controller, the system energizes and initiates the conveying cycle. The following components energize:

∙The vacuum pump motor starter.

∙The vacuum pump vent valve.

∙The sequencing valve above the first on-line vacuum receiver that requires material.

The vacuum pump draws vacuum to that receiver. When the receiver is full or the time interval elapses, the controller then signals the atmospheric valve above the next on-line receiver requiring material to energize, allowing material to convey to that receiver. The conveying sequence continues to the last on-line vacuum receiver requiring material.

When the time interval for the last receiver elapses or the receiver is full, a new conveying cycle begins at the first on-line vacuum receiver requiring material.

Note: The sequence of events listed above is a generalized description of what occurs when a controller is activated. Consult your specific controller manual for an accurate depiction of these events.

Vacuum Switch (VS) Operation

A high vacuum switch is mounted inside a pump package junction box. It is preset to close at 14” Hg (475 millibars) and is not adjustable. The vacuum switch protects the pump package from motor damage caused by high amperage draw and strain on the blower.

Pumps typically draw a vacuum of less than 5” Hg (170 millibars) only when air is pulled into the system and 8” to 12” Hg (271 to 339 millibars) while conveying.

If system vacuum should reach 14” Hg (475 millibars), the high vacuum switch closes. The pump package tries to clear the line for three seconds, then moves to the next on-line vacuum receiver. The normal conveying cycle continues. If high vacuum keeps occurring, the pump continues with attempts to clear the line.

See your specific controller manual for additional operation information.

Conveying System Mechanical Components Chapter 4: Operation 79 of 138