Optimizing Performance of Open well Submersible Pumps in Low Head Conditions: A Case Study on Enhancing Efficiency with Lubi Team Intervention.


Client: Residential Society located at Coimbatore, Tamil Nadu, INDIA

Complain: Open Well Submersible Pump Consuming High Ampere


Nameplate Of Pump
Nameplate Of Pump

The LHL-9BG pump is designed to pump water from open wells, especially in areas where the possibility of fluctuation in water levels is high. These pumps can also be used at:


  • Community water supply from open wells
  • Fountains
  • Irrigation from Canals / River belt
  • Water supply for high-rise buildings


Lubi's Open-well Submersible Pump (LHL Series)
Lubi's Open-well Submersible Pump (LHL Series)


Note: This pump is recommended for drawing only clean water.




A residential society at Coimbatore had installed our LHL-9BG Open Well Submersible Pump in their underground tank to draw water for domestic consumption.

One day, their pump operator noticed (on the Pump’s control panel) that the pump was drawing too much power, and so he informed the management who immediately called us up on our toll-free helpline number to register a complaint.


Control panel
Control panel



  • Customers can register a complaint by calling our toll-free number, after which they will receive a text message with information about the complaint as well as the contact details of our service engineer.
  • Our Engineer usually calls up to fix an appointment as per the electricity schedule of the area - as there are frequent power disruptions at some places.


Our service engineer reached the site as per the pre-scheduled appointment.


After looking at the Control Panel and checking other basic parameters, our technician too observed that the pump was drawing a lot of power.


In order to conduct a detailed inspection, our technicians took the following steps:


  • The technician first checked the power supply using a Clip-On Meter. He checked all the points – Mains as well as the Pump’s Electric Panel (both inward and outward supply).
    Checking power supply
    Checking power supply


  • He then checked whether the pump’s discharge was proper or not.
  • He then calculated the duty point and checked if the head of the pump was at the correct location.




  • The technician observed on the pump’s panel that the pump was drawing too much power. However, he noted there was no problem with the (input) voltage from the mains.
  • There was no problem with the discharge of the water; water was flowing normally.
  • Upon checking the head of the pump, the technician found that the pump was working on a low head. This was contrary to what the dealer had instructed the customer.


Note: The dealer recommends a specific pump after carefully evaluating the purpose, geography (or site inspection), and various other requirements of the customer. It is highly recommended that the customer strictly follow the guidelines issued by the dealer.



Our technician explained to the customer that he was using the pump on a low head which was against prescribed norms. However, the customer was adamant that it was not possible for him to change the head. He requested that we find an alternative solution.


  • The technician sent the pump to our service centre for an alternative solution, which was to reduce the diameter of the impeller.
  • The service centre technicians removed the impeller, reduced its size to 11 mm, and refitted it back to the pump. They then checked the pump at different heads and found it to be working flawlessly without consuming any additional amperage.


Note: Change in impeller diameter without the go-ahead from company officials is not recommended.


  • The pump was sent back to the customer, where, upon installation, it worked perfectly while consuming just 15 amps - as recommended.

The customer thanked the technician, as he was delighted with the service and with the fact that he didn’t have to buy a new pump.



  • An Open-Well Submersible Pump should always be installed and operated precisely as per the instructions issued by the company.
  • Any change in the head (High-Low) could cause serious malfunction in the working of the pump. There is also a risk of the motor getting burned out.
Frequently Asked Questions (FAQ’s):


Q. What is the recommended power supply for the LHL-9BG open well submersible pump?

A. The ideal power supply for the 3-Phase, LHL-9BG submersible pump is 380 To 415 Volts.


Q. What could happen if a high-head pump is made to work on a low-head?

A. If a high-head pump is made to work on a low head, it could cause serious problems to the motor of the pump. The motor may draw a lot of additional power than recommended, which could lead to overheating and even accidents - if left unchecked for a long.


Q. How can we protect a submersible pump's winding?

A. Before installing a new water-cooled submersible pump, always open both the drain plugs of the pump’s motor and fill it with clean water from one end, till it drains from the other side.


Q. What is the significance of submersible pump control panel?

A.  The main objectives of a control panel are to:

1) Switch On or Switch Off the pump

2) Monitor the voltage and ampere of the submersible pump motor

3) Protect the submersible pump motor from overload

4) Provide capacity torque to the submersible pump motor


By installing a control panel for your submersible pump, you can:

1) Save electricity

2) Protect motor from burning out.

3) Ensure your motor keeps running smoothly for a long time.



A submersible pump will last longer and work more efficiently if you follow the recommendations mentioned below along with the other essentials mentioned in the owner’s manual.


  • Before buying a pump, properly examine your site and plan your requirements. This information is very critical for the dealer/company to recommend the most appropriate pump for your specific needs.
  • Before installing a new pump, always open both the drain plugs of the pump’s motor and fill it with clean water until it drains from the other side.
  • Always ensure that the submersible pump remains “completely” submerged in water. You can also install external auto cut-off sensors (for additional safety) to prevent dry runs.
  • Make sure your pump operates at the duty point declared by the manufacturer for maximum efficiency. Please contact our customer support team to learn more about duty points.
  • Always ensure that the push button on the control panel of the pump is working properly. This is imperative for the smooth functioning of the pump.
  • Always use good quality cable for any kind of wiring to avoid any untoward incidents. A poor-quality supply cable could also result in a loss of voltage, thereby impacting the performance of the pump.
  • To prevent leakages in winding cable, try to keep joints minimal and always hire a trained professional to do the job.
  • Check the motor’s continuity, insulation, and resistance using ohms and Megger Meters.
  • Get your pump inspected at regular intervals.


For smooth and uninterrupted working of your pump, always follow the instructions and standard operating procedure issued by the manufacturer.