Overload Protection
3-phase LSG/LSGX-Series grinder pumps require overload
protection in the control panel. The motor control unit shall be
approved and shall be properly sized or adjusted for the full load
input power indicated on the pump nameplate. It is important to
properly adjust or select the motor control overload protection.
The full load amperes on the nameplate should be used as a
baseline, but it is important to consider that events such as supply
voltage variation or large solids passing through the pump can
temporarily increase current draw. To avoid possible nuisance
tripping, it may be necessary to adjust overloads to a value slightly
higher than the full load input power indicated on the pump
nameplate.
Thermostat
1-phase pump models are protected from locked rotor and
running overloads by a thermal overload (thermostat) integrally
mounted to the motor and wired to shut down the pump if
overheating occurs. The thermostat resets automatically after the
pump has cooled.
Power and Control Cords
RISK OF ELECTRIC SHOCK
Do not remove cord and strain relief, and do not connect
conduit to pump.
The power and control cords cannot be spliced; a junction box
may be used.
IMPORTANT: Each cord has a green lead. This is the ground wire
and must be grounded properly per NEC
Float Switches
Pump On and Off cycles are controlled by float switches in the wet
well (basin). Automatic pumps have a "piggyback" float switch
attached to the side of the pump, while manual pumps have float
switches attached to the control panel. Refer to control panel or
switch instructions for proper electrical connection.
Float Sequence: Piggyback (Automatic Models)
1.
As the liquid level in the basin rises, the float tilts, closing the
switch. This starts the pump.
2.
The pump runs until the liquid level falls below the PUMP OFF
level of the float (factory set at 7 in), emptying the basin.
Float Sequence: Simplex (Manual Models)
1.
As the liquid level in the basin rises, the PUMP OFF float tilts,
closing the switch. This level must be set at a minimum of
7 in. As the liquid level continues to rise, the PUMP ON float
tilts. This switch closes, starting the pump.
2.
The pump runs until the liquid level falls below the PUMP OFF
float, emptying the basin.
3.
In the event of a malfunctioning float switch, control relay, or
pump, the liquid level rises and tilts the HIGH LEVEL ALARM
float. The alarm system will activate.
– 6 –
®
and/or local codes.
Copyright © Liberty Pumps, Inc. 2019 All rights reserved.
Float Sequence: Duplex (Manual Models)
1.
As the liquid level in the basin rises, the PUMP OFF float tilts,
closing the switch. As the liquid level continues to rise, the
LEAD PUMP ON float tilts. This switch closes, starting the lead
pump.
2.
The pump runs until the liquid level falls below the PUMP OFF
float, emptying the basin.
3.
On the next rise of the liquid level, the other pump will start
on the LEAD PUMP ON signal. The pumps will continue to
alternate their cycles.
Note: The ON/OFF float switch differential should be set as to
not exceed 12 starts per hour.
4.
If the liquid level rises to the LAG PUMP ON float, the second
pump will start. Both pumps will run until the liquid falls
below the PUMP OFF float, emptying the basin.
5.
In the event of a malfunctioning float switch, control relay, or
pump, the liquid level rises and tilts the HIGH LEVEL ALARM
float. The alarm system will activate.
Wiring Instructions
RISK OF ELECTRIC SHOCK
Always disconnect pump(s) from power source(s) before
handling or making any adjustments to either the pump(s),
the pump system, or the control panel.
All installation and maintenance of pumps, controls,
protection devices, and general wiring shall be done by
qualified personnel.
All electrical and safety practices shall be in accordance with
the National Electrical Code
Health Administration, or applicable local codes and
ordinances.
L2
L1
START
RELAY
START CAP
RUN CAP
Figure 1. Wiring Diagram 1-Phase, External Capacitor
208V/230V 3PH
BLK
L1
RED
ORN
PNK
L2
BRN
WHT
YEL
VIO
L3
BLU
Figure 2. Wiring Connections 3-Phase
®
, the Occupational Safety and
Black (2)
5
Red (8)
1
2
White (7)
575V 3PH
440–480V 3PH
L1
L1
BLK
BRN
RED
L2
PNK
ORN
WHT
L2
L3
VIO
YEL
BLU
L3
BLK
PNK
VIO
5647000K