© 2018 Novatec, Inc. All Rights Reserved
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Instruction Manual VPD-25 IM 12 FEB 2018
1.0 INTRODUCTION
The Novatec VPD vacuum pump is designed to pneumatically convey plastic pellets or powders in a
vacuum conveying system. It does this by creating a vacuum to “pull” air through the piping system.
Plastic pellets or powders are introduced into the moving air stream in various ways, including
through the use of probes, pick-up tubes, and rotary air locks. The VPD is used in conjunction with
vacuum chamber station valves, etc. to form the conveying system, which is controlled with either
Master Control or Distributed Control Panels. Several vacuum power units may be designed into the
system as required. Vacuum conveying systems typically distribute material from silos, surge bins,
blenders, or drying hoppers to processing machinery.
2.0 WARNING
Always disconnect power before servicing. Only qualified technicians should service, maintain, or
repair the VPD. Before using this equipment, read in detail the product bulletins and other
information found in this manual. A safe installation is necessary before operating the equipment.
The instructions should be understood and followed before installing or operating the equipment.
3.0 OPERATING LIMITATIONS
Operating At Higher Altitudes…3000 Ft Above Sea Level or More
Atmospheric pressure is lower at higher elevations and as a result, the compression of air by the pump
requires more work for vacuum conveying. In these higher altitude applications the pressure relief
valve of VPD pumps must be adjusted on site to prevent the pump from damaging itself or the motor
by attempting to compress air of reduced density to an unsafe level. Contact Novatec Engineering or
Service at the number on the front cover of this manual when operating the pump at 3000 ft or higher
elevation.
Blower exhaust temperature and motor cooling are a function of both vacuum level and elevation.
Blower exhaust temperature must not exceed 300°F to avoid premature blower failure.
Decreased motor FLA limits may require alternate overload protection or increased frame size / hp.
3.1 Seek Time
Excessive starting and stopping of the pump will reduce blower and motor life and void the
warranty. Seek Time is a control parameter that allows your pump to operate for short
periods in vacuum break mode (no vacuum loading) while the system control searches for
new demands. Using the Seek Time feature, pump starts must be limited to 12 per hour to
prevent premature failure. The minimum Seek Time for a pump is 240 seconds to prevent
exceeding 12 starts per hour. Optimum Seek Time may be set dependent upon pump
capacity, utilization, number of stations, capacity of each vacuum chamber, and individual
station throughputs. (See your control panel instruction manual for information on Seek
Time)
