Detecting Float Switch Cable Cuts and Restoring Continuity in a Sewage Pump: A Case Study


Pump Model: LAP-2115-F / 1.00 HP / 1 PH / 2" OUTLET


Client: Residential Society at Chennai, Tamil Nadu.


Lubi sewage pump Lap
                     Lubi's Sewage Pump LAP Series


  • A highly populated residential society in Chennai, Tamil Nadu had installed several of our sewage pumps in their water treatment plant.
  • Given Chennai's severe water scarcity, this plant was a strategic initiative by the society to secure consistent water supply.
  • One day, while overseeing the plant operations, the vigilant operator observed a disruption in the functioning of one of our sewage pump (LAP-2115-F), which he had recently installed. The LAP-2115-F played a crucial role in propelling water through the treatment process.
  • Concerned about this unexpected development, the operator immediately deactivated the system and notified the management, who promptly reached out to us via our toll-free helpline to register a formal complaint.


  1. 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.
  2. Our Engineer usually calls up to fix an appointment as per the electricity schedule of the area - as there are frequent power disruptions in some places.


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




Upon reaching the site, our service engineer immediately commenced the inspection to validate the reported problem and identify its root cause.


  • In order to diagnose the issue, our engineer performed a series of standard checks, starting with an assessment of the power supply. He first checked the supply voltage using a clip-on meter.
  • Subsequently, our engineer proceeded to assess the cable's continuity using a megger meter.
  • Following the continuity check of the cable, our engineer requested the operator to remove the pump for further examination.




  • While conducting the pump inspection, our engineer observed that the power supply voltage was within the appropriate range.
  • When examining the cable's continuity, our engineer discovered a lack of continuity.
  • Upon inspecting the float switch cable, our engineer identified a similar issue with continuity. He then manually inspected the float switch cable and saw a cut in it.


Cut Found In Cable
Cut Found In Cable



  • A float switch in a sewage pump serves as a level sensor and helps to control the operation of the pump. It ensures that the pump starts and stops automatically, based on the water level in the sewage pit or tank. This helps to prevent overflow and damage to the pump, and ensures efficient and effective pumping of the sewage. If there is a problem with the float switch, the sewage pump may not start or stop correctly, leading to potential overflow or pump malfunction. 
Cut Found In Cable


  • Upon identifying the cable cut in the float switch, our engineer promptly brought it to the attention of the operator and recommended him to get it replaced.
  • After receiving approval for the replacement, our engineer proceeded to install the new float switch and assessed its continuity with a megger meter. This time, the continuity was confirmed.
  • Following this, our engineer conducted a brief "no-load test" for 2 seconds before starting the pump.
  • He re-installed the pump and when the operator started the system, the pump was running perfectly.



  • A "no-load test" is a simple test where a motor or pump is run without any load or resistance, allowing engineers to check its performance and ensure it operates smoothly and quietly. It helps to identify potential issues before the motor or pump is put under actual workload conditions.


  1. Avoid using the pump's cables to lower it; instead, use a rope for safe and proper lowering.
  2. The recommended power supply for a single-phase LAP-2115-F pump is 180 to 230 Volts.
  3. Power fluctuations can cause serious damage to all electrical appliances. Use a stabilizer if you are witnessing voltage fluctuations.
  4. Prior to the installation of the pump, it is recommended to use a megger meter to check the continuity of the winding insulation.
  5. 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.
  6. Regular inspection and servicing of the pump can help detect many issues beforehand.


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