Gorman-Rupp Pumps VS6A60-B 1352521 and up - Manual (Page 14)

OM-06014 ULTRA V SERIES
PAGE B - 7 INSTALLATION
ard 1‐inch NPT fitting, or the Air Release Valve may
be installed in a spool flange between the two dis­
charge check valves.
Connect the valve outlet to a bleed line which
slopes back to the wet well or sump. The bleed line
must be the same size as the outlet opening or lar­
ger, depending on which Air Release Valve is being
used. If piping is used for the bleed line, avoid the
use of elbows whenever possible.
NOTE
For multiple pump installations, it is recommended
that each Air Release Valve be fitted with an inde­
pendent bleeder line directed back to the wet well.
If multiple Air Release Valves are installed in a sys­
tem, do not direct bleeder lines to a common mani­
fold pipe. Contact your Gorman‐Rupp distributor or
the Gorman‐Rupp Company for information about
installation of an Automatic Air Release Valve for
your specific application.
DRIVE ARRANGEMENTS
Special consideration must be given to drive ar­
rangements for staged pumping applications.
Since pump installations are seldom identical, this
section provides some general recommendations
for selecting drive arrangements for staged
pumps. Consult the factory for information regard­
ing your specific application.
Dual Motor Drives
It is recommended that each pump be directly driv­
en by its own electric motor, either through coup­
lings (see Figure 3) or a belt arrangement (see Fig­
ure 4).
Each motor should be independently operated
through a reduced voltage solid state (RVSS)
starter, a variable frequency drive (VFD) or an ad­
justable speed drive (ASD). In this arrangement,
the motor powering the lower stage pump should
be programmed to start first and “ramp up” to full
condition speed, then the second stage pump mo­
tor should start and “ramp up” to full condition
speed. Pump motor shutdown should be pro­
grammed in reverse order, with the second stage
pump motor “ramping down” before shutting off,
then the first stage pump motor “ramping down”
and shutting off. This “ramp up” and “ramp down”
configuration helps reduce inrush current on star­
tup and destructive “water hammer” on both star­
tup and shut down.
Figure 3. Recommended Dual Motor Direct
Drive Arrangement
Figure 4. Recommended Dual Motor Belt
Drive Arrangement
Single Motor Belt Drives
In staged applications where both pumps are belt
driven by a single motor (either through a syn­
cronous [cog] or V‐belt configuration) certain ar­
rangements must be used in order to ensure prop­
er operation.