Electrical service and operation – Liberty Pumps 290-Series User Manual

Page 6

Follow the instructions provided with your duplex control device. Each float must be

free to move throughout its

travel and not contacting the pump body, piping, or other objects. Connect an individual discharge pipe to each

pump. IMPORTANT: DO NOT REDUCE THE DISCHARGE PIPE SIZE BELOW THAT WHICH IS PROVIDED ON

THE PUMP. Contact Liberty Pumps or other qualified person if you have any questions regarding proper pipe sizes

and flow rates. To eliminate fluid recycling in duplex installations, it is necessary to have a check valve on each

discharge line prior to tying the two discharges into one common line. Depending on the height of your basin, the

check valves may either be installed inside the basin or outside the basin. Mount the basin cover(s) making sure

they are properly sealed.

Installation of Remaining Discharge: Unions or flexible connectors should be installed to facilitate removal of the

pump if necessary. Free-flow swing check valves should be installed on each discharge after the union and prior to

the gate valve to prevent the back flow of liquid or gas. A check valve on each discharge line, prior to tying into one

common line, is necessary to prevent the recycling of fluid from one pump to the other. A gate valve is recommended

after the check valve to allow for periodic cleaning of the check valve or removal of the pump. The remainder of the

discharge line should be as short as possible with a minimum number of turns to minimize friction head loss.

Contact Liberty Pumps or other qualified person if there are questions regarding proper pipe size or flow rates. (All

Liberty effluent/dewatering pumps come equipped with an air bleed hole in the base of the pump to help prevent

airlock. A small spray of water from this hole is normal while pump is running.)



Risk of electric shock. Always disconnect the pump from the power source before handling or making adjustments.



The electrical connections and wiring for a pump installation should only be made by qualified personnel.



This pump is supplied with a grounding conductor or a grounding type attachment plug. To reduce the risk of electric

shock, be certain that the grounding conductor is connected only to a properly grounded control panel or, if equipped

with a grounding type plug that it is connected to a properly grounded, grounding type receptacle.



DO NOT bypass grounding wires or remove ground prongs from attachment plugs.



DO NOT use an extension cord.



This pump requires separate, properly fused and grounded branch circuit. Make sure the power source is properly

sized for the voltage and amperage requirements of the motor, as noted on the pump nameplate.



The electrical outlet or panel shall be within the length limitations of the pump power cord, and at least 4 feet above

floor level to minimize possible hazards from flood conditions.



The installation must be in accordance with the National Electric Code and all applicable local codes and ordinances.

When the risk of property damage from high water levels exists, an independent high water alarm or

back up pump system should be installed.

All FL-Series automatic models (designated with the letter "A") and Models 253, 283 and 293, come factory-equipped with

a float switch mounted to the pump. These models come with two cords - one to the float switch and the other to the

pump motor. The switch cord has a series (piggyback) plug enabling the pump (motor) cord to be plugged into the back

of it. The purpose of this design is to allow manual operation of the pump.

For manual operation, or in the event of switch failure, the pump cord can be separated and plugged into the electrical

outlet, directly bypassing the switch

(see Fig. 4).

4. Electrical Service and Operation

DON’T!

Fig. 1 Piggyback plug installation.

TEMPORARY

MANUAL

OPERATION

NORMAL

Fig. 4 – Temporary manual operation