Often people living in cities pose us this query as they use two different pumps to pump water up to same overhead water tank. One pump is installed directly on municipal supply pipe line and the second pump is bore-well submersible pump pumping water directly to overhead water tank. So there are two pumps but only one is operated at one point of a time. Buyer wishes that only one alarm be installed as there is only one overhead water tank. Above situation creates two scenarios.
Scenario-Yes is when pump-1 is operated (start & stop) by a single switch (tick-tock switch) and the second pump also is also operated by similar kind of single switch. This single switch may be like the one you have for lights and fans or even an MCB being used as motor switch. This single switch technically confirms that both the pumps are of similar kind and have only one capacitor (called running capacitor) involved its working. So when such similar pumps are there it is possible to use one water overflow alarm device for both the water pumps. The diagram below shows the basic layout needed.
Basically what is done is that double pole (DP) switches are installed to control input supply of motor starter (or motor). Alarm device is connected to supply phase before DP switches and alarm neutral is connected after DP switches. So when no pump is running overflow alarm device neutral is cut, keeping it in off mode. When any of pump is started alarm device gets connected to neutral (through DP switch) and comes alive (LED starts glowing). When water tank reaches full level overflow alarm sounds alarm and motor is switched off, overflow alarm also goes off. This works when any of DP switch is used.
Last but not the least, please note that above can be done only when two critical conditions are fulfilled.
Both the pumps must be operating on same phase and neutral line.
Both the pumps must be single switch (single capacitor) run.
Scenario-No- is when any of above condition is not fulfilled. In such scenario you may have one or both pumps being operated by two push button (green push to start and red push to stop) or you may have pumps which are connected to different phases of power supply.
It will be better that a good technician is involved to configure above electrical connections. We at SensaSwitch will be happy to share more for any concerns or queries, please call or whatsapp us during office hours at our helpline 9814055314.