Bell & Gossett IM179 R02 Single Phase, Single Seal Grinder Pump User Manual

Page 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”

backwards 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

⁄

” (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 relief 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 voltage 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

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 gallons

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 storage

provided by the basin, save some space for reserve stor-

age capacity. See Diagrams and Charts in Float Switch

Chart Section.
PANEL WIRING DIAGRAMS

Our control panels are shipped with instructions and wir-

ing 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