Little Giant 3-MD-MT-HC Manual

Franklin Electric
Oklahoma City, OK 73127
www.franklinwater.com
CustomerService@lgpc.com
SAFETY GUIDELINES
CAUTION: To reduce the risk of electric shock, pull plug before
servicing this pump.
Read all instructions and safety guidelines thoroughly. Failure to
follow the guidelines and instructions could result in serious bodily
injury and/or property damage.
Do not pump flammable liquids such as gasoline or fuel oil.
Make sure pump is grounded.
During operation the area surrounding the pump may be covered
with water. Take care when handling the pump. Do not disconnect
the plumbing connections when pump is in operation.
Do not stand in water when changing fuses.
pUmp coNSTrUcTIoN
The patented Little Giant magnetic drive pump design consists of a
cylindrical drive magnet attached to the motor shaft which rotates
around a chemical resistant plastic separator housing. Inside this
housing is a magnet completely encapsulated in chemical resistant
plastic, and is fixed to the impeller. The impeller assembly is free
to rotate on a spindle that is supported at both ends. The spindle
is held captive and does not turn. Front and rear thrust washers
are utilized as wear bearings. The washers are held captive and
do not revolve. This prevents wear on the shaft. With the magnetic
coupling the motor drives the impeller. This coupling eliminates
the conventional shaft seal and its possibility of leakage.
Two series are available. The HC series handles highly corrosive
chemicals at elevated temperatures because of the unique
materials used in its construction. The SC series handles semi-
corrosive fluids. Both series are available with various size pumps,
and are available in 115V or 230V, 50/60 Hz versions.
The HC models utilize a carbon bushing between the impeller and
spindle. The use of this carbon bushing will allow these pumps
(HC series) to run dry (without fluid) for up to eight hours at a
time. Do not allow the SC models to run dry. They do not have the
carbon bushing and heat build up caused by friction will damage
the parts when SC models are run dry.
All wetted parts can be serviced by removing 4 wing nuts that hold
the volute to the housing. The pump head components can easily
be replaced in the field if necessary.
pUmp mATErIALS
The plastic parts on SC series pumps are made of glass filled
polypropylene. The plastic parts on the HC series pumps are glass
filled PPS. The spindle shaft which is stationary and the captive
thrust washers (front and rear) are alumina ceramic. The O-ring
seal is Nitrile for the SC series, and Fluoroelastomer (FKM) for HC
series. The HC series utilizes a pure carbon bushing in the impeller
to enable the pump to run dry for periods up to eight hours at a
time.
3-mD-mT-hc
INSTALLATIoN
Your Little Giant pump is delivered to you completely pre-
assembled and pretested from the factory. It is ready for immediate
use. The pump may be installed in any position. It may be
mounted vertically with the pump head down. Proper plumbing
connections should be made, see specification table to determine
what size intake and discharge your pump has. Use a thread
sealer on all pipe connections and hand tighten only. Note: On
HC models a roll of PTFE pipe seal tape is supplied. Do not use a
wrench to tighten the HC model connections, excessive force may
damage the plastic part. Make sure the wing nuts are tight before
operating the pump. Motor nameplates list all electrical data. Make
sure the pump is connected to proper voltage before operating.
When wiring pumps with no plug, the green (or green/yellow) wire
is the ground. The other two wires are line (live). Do not allow
the SC models to run dry (without fluid). However, because the
HC models utilize a carbon bushing in the impeller they maybe
allowed to run dry for periods up to eight hours at a time. These
pumps are not submersible, operate the pumps only in the in-line
mode. Do not put the units in liquid. Pump should be installed in
a dry area and protected from splash. These pumps are not self
priming models, they must be installed so that the pump head
(volute) is flooded at the time the pump is to be started. That is,
the inlet of the pump must be below the level of the surface of the
liquid being pumped. (Figure 1).
Do not restrict the intake side of the pump. Connections on the
intake side should not be of smaller inside diameter pipe or
tubing or hose than the intake inside diameter of the intake thread
designation. If reduced flow is required restrict the discharge
side. Installing a valve or other type of restriction device on the
discharge side is the proper method for reducing flow from the
pump. When using a valve the pump can be throttled to provide
various flow rates and pressures without harming the motor or
the pump parts. The motors on these models contain sleeve type
bearings. These bearings should be oiled every six months with
two to three drops of S.A.E. 20 weight non-detergent oil. The oil
holes are located on top at each end of the motor.
FIGUrE 1
993236 - 07/2013 REV. 001
1