VL-VLP IM 19 JUNE 2017 © 2017 NOVATEC, Inc. All Rights Reserved
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Prop Valve A Time (PValve/PVA) and Prop Valve B Time (PValve/PVB)
, each measured
in seconds, is the amount of time dedicated to the loading of two materials with the use of an
optional, external Proportioning Valve. The Proportioning Valve is installed on the material
inlet of the VL or VLP loader (see separate instructions, accompanying the valve) and
shuttles internal plungers between allowing A (typically virgin) and B (typically regrind)
materials to be loaded during the course of the Motor-On time. Time setting A counts down
during loading at which time the valve switches to allow the B time setting to take over. A
and B will repeat until the Motor-on time expires.
Short A and B time settings will allow multiple ‘layers’ of virgin and regrind materials to be
loaded for rough ‘mixing’ of the two materials during loading. However, short cycles require
each flow of material to start, then stop, possibly resulting in very little material being
conveyed to the loader. Trial and error settings of Motor-on time and A and B times are
suggested to optimize these settings.
MATERIAL LOAD TIME = FILL TIME – PURGE TIME
Because the functions are identical, the term PURGE time is used for purging systems
and
pocket conveying systems for cleaning out the conveying line after loading.
Here it is visually...
Purge or
Pocket Valve
CLOSES to
Material flow
LOAD Time
(purge valve
open)
PURGE Time
(purge valve closed)
Times are set in seconds.
Fill Time
(Vacuum Motor “ON”)
Vacuum Motor
“ON”
Vacuum
Motor “OFF”
