4
PIPING
Discharge piping should be no smaller than the pump
discharge diameter and kept as short as possible,
avoiding unnecessary fittings to minimize friction losses.
Install an adequately sized check valve to prevent fluid
backflow. Backflow can allow the pump to “turbine” back
-
wards and may cause premature seal and/or bearing
wear. If the pump is turning backwards when it is called
on to start the increased torque may cause damage to
the pump motor and/or motor shaft and some single-
phase pumps may actually run backwards.
Install an adequately sized gate valve
AFTER
the check
valve for pump, plumbing and check valve maintenance.
Important – Before pump installation.
If pumping waste
water containing solids, drill a
3
⁄
16
” (4.8mm) relief hole in
the discharge pipe. It should be located within the wetwell,
2” (51mm) above the pump discharge but below the
check valve. The relief hole allows any air to escape from
the casing. Allowing liquid into the casing will insure that
the pump can start when the liquid level rises. Unless a re-
lief hole is provided, a bottom intake pump could “air lock”
and will not pump water even though the impeller turns.
All piping must be adequately supported, so as not to
impart any piping strain or loads on the pump.
The pit access cover must be of sufficient size to allow for
inspection, maintenance and crane or hoist service.
WIRING AND GROUNDING
Important notice: Read Safety Instructions before
proceeding with any wiring.
Use only stranded copper wire to pump/motor
and ground. The ground wire must be at least
as large as the power supply wires. Wires should
be color coded for ease of maintenance and
troubleshooting.
Install wire and ground according to the National
Electrical Code (NEC), or the Canadian Electrical
Code, as well as all local, state and provincial codes.
Install an all leg disconnect switch where required
by code.
Disconnect and lockout electrical power before
performing any service or installation.
The electrical supply voltage and phase must
match all equipment requirements. Incorrect volt-
age or phase can cause fire, motor and control
damage, and voids the warranty.
All splices must be waterproof. If using splice kits
follow manufacturer’s instructions.
Select the correct type and NEMA grade
junction box for the application and loca-
tion. The junction box must insure dry,
safe wiring connections.
Seal all controls from gases present which
may damage electrical components.
FAILURE TO PERMANENTLY
GROUND THE PUMP, MOTOR AND
CONTROLS BEFORE CONNECTING
TO POWER CAN CAUSE SHOCK,
BURNS OR DEATH.
SELECTING AND WIRING
PUMP CONTROL PANELS AND SWITCHES
FLOAT SWITCH TYPES
There are two types of float switches available for use
with 2 HP, single phase grinder pumps; single action con-
trol switches and wide angle mechanical switches.
Single action control switches can only be connected
through a control panel. Connecting them directly to a
pump will cause rapid cycling and may burn up the mo-
tor, and/or the motor start switch and/or the float switch.
If using single action switches with a control panel please
see the
Float Switch and Panel Section.
Model A2G33 wide angle pump float switches can be
hard wired directly to the pump. Wide angle switches can
operate the pump via connection to a control panel. The
tether length or distance from the switch body to the piv-
ot point controls the On and Off points and the amount
pumped in one cycle. The pivot point is where the float is
attached to the discharge pipe.
See Figures 1 and 2.
SETTING THE FLOAT SWITCHES
There are no absolute rules for where to set the float
switches, it varies from job to job.
Suggested Rules to Follow:
All floats should be set below the Inlet pipe!
Off Float:
Best: set so the water level is always above the
top of the pump (motor dome).
Next Best:
set so the wa-
ter level is not more than 6” below the top of the pump.
On Float:
set so the volume of water between the On
and Off floats allows two (2) HP and larger pumps to run
a minimum of 2 minutes. Basin literature states the gal-
lons
of storage per inch of basin height.
Lag/Alarm Float(s):
should be staggered above the
Off and On floats. Try to use most of the available stor
-
age provided by the basin, save some space for reserve
storage capacity.
See Diagrams and Charts in Float Switch
Chart Section.
PANEL WIRING DIAGRAMS
Our control panels are shipped with instructions and
wiring diagrams. Use those instructions in conjunction
with this IOM. Electrical installation should be performed
only by qualified technicians. Any problem or questions
pertaining to another brand control must be referred
to that control supplier or manufacturer. Our technical
people have no technical schematics or trouble shooting
information for other companies’ controls.
ALARMS
We recommend the installation of an alarm on all Waste-
water pump installations. Many standard control panels
come equipped with alarm circuits. If a control panel is
not used, a stand alone high liquid level alarm is avail-
able. The alarm alerts the owner of a high liquid level in
the system so they can contact the appropriate service
personnel to investigate the situation.
WARNING
Hazardous
voltage
WARNING
WARNING
Summary of Contents for GOULDS RGS Series
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