Automatic Water Pump Controller Circuit Using 555 Timer IC
This article explains how to build an automatic water pump controller circuit using 555 timer IC. The automatic water pump controller circuit using 555 timer IC helps in switching pumps automatically. With this automatic water pump controller circuit using 555 timer IC, you can manage overhead and underground tanks easily. The automatic water pump controller circuit using 555 timer IC also provides manual and auto modes.
Building an automatic water pump controller circuit using 555 timer IC requires few components. The automatic water pump controller circuit using 555 timer IC uses BC547 transistor, relay, and resistors. This automatic water pump controller circuit using 555 timer IC is safe and effective. You can assemble the automatic water pump controller circuit using 555 timer IC on a Zero PCB. Learn step-by-step how to make an automatic water pump controller circuit using 555 timer IC at home.
Introduction
Managing water levels in overhead tanks and underground sumps is a daily challenge in most homes. Leaving the pump on for too long causes overflow, while forgetting to start it leaves tanks empty. The solution is simple — an automatic water pump controller circuit using 555 timer IC.
This circuit monitors the water level and automatically turns the pump ON and OFF. It also includes manual mode for emergencies, making it versatile and practical.
Materials for the Project
| Component | Value / Type | Quantity | Reference | Buy Link |
|---|---|---|---|---|
| 555 Timer IC | NE555 | 1 | IC1 | Buy Here |
| BC547 NPN Transistor | TO-92 | 2 | Q1, Q2 | Buy Here |
| Resistors | 1kΩ 0.25W | 2 | R5, R6 | Buy Here |
| Resistors | 22kΩ 0.25W | 3 | R1, R2, R8 | Buy Here |
| Resistor | 180kΩ 0.25W | 1 | R7 | Buy Here |
| Resistors | 1MΩ 0.25W | 2 | R3, R4 | Buy Here |
| LED | 5mm, 1.5V | 1 | D2 | Buy Here |
| Diode | 1N4007 | 1 | D1 | Buy Here |
| Capacitor | 100nF (104) | 1 | C1 | Buy Here |
| Relay | 12V SPDT (30A) | 1 | RL1 | Buy Here |
| Switch | SPST | 1 | SW1 | Buy Here |
| Connectors & IC Base | 4-pin | As needed | – | Buy Here |
| Zero PCB | General purpose | 1 | – | Buy Here |
Useful Tools
| Tool | Quantity | Purpose / Notes | Click & Buy |
|---|---|---|---|
| Soldering Iron Kit | 1 | For making permanent connections | Click & Buy |
| Solder Wire (60/40, 0.8mm) | 1 | Electrical soldering | Click & Buy |
| Wire Stripper & Cutter | 1 | Stripping jumper wires | Click & Buy |
| Mini Screwdriver Set | 1 | For module and relay terminal screws | Click & Buy |
| Multimeter | 1 | Testing voltages and continuity | Click & Buy |
| Hot Glue Gun (optional) | 1 | Securing components in place | Click & Buy |
| Small Pliers | 1 | Holding and bending wires | Click & Buy |
| Heat Shrink Tubing Set | 1 | Insulating exposed wires | Click & Buy |
Working Principle
The automatic water pump controller circuit using 555 timer IC works by sensing water levels in the tanks:
- Water Low Condition
- When water level drops in the overhead tank, the sensing wires detect low conductivity.
- This triggers the 555 timer, activating the BC547 transistors.
- The relay energizes and switches ON the pump.
- Water Full Condition
- When water level reaches the high mark, conductivity between sensing probes completes the circuit.
- The 555 timer resets and deactivates the relay.
- The pump switches OFF automatically.
- Manual Mode
- The MCB or manual switch can still operate the pump directly, bypassing the auto system.
- Useful for maintenance or emergency operations.
Circuit Diagram Explanation
- 555 Timer IC is configured as a bistable multivibrator.
- BC547 transistors (Q1, Q2) act as electronic switches to control sensing signals.
- Resistors R1–R8 define biasing and timing.
- Capacitor C1 provides noise filtering and stability.
- Relay RL1 (30A contact rating) drives the water pump.
- Diode D1 (1N4007) protects the relay coil from back EMF.
- LED Indicator shows circuit activity.
- Switch (SW1) allows toggling between auto and manual mode.
Download Circuit Diagram
Step-by-Step Guide to Build
- PCB Preparation
- Print the PCB layout with grid markings.
- Place it over a Zero PCB and align holes.
- Component Placement
- Insert resistors, diodes, and capacitor first.
- Place IC socket for 555 timer IC.
- Add BC547 transistors and relay.
- Soldering
- Carefully solder components as per layout.
- Ensure no short circuits between tracks.
- Connections
- Connect AC supply and pump wires via the relay contacts.
- Attach water-level sensing wires to the tank.
- Testing
- Switch ON in manual mode to confirm relay operation.
- Switch to Auto mode:
- Pump should start when water is low.
- Pump should stop when tank is full.
Safety Precautions
- Always test the circuit with low-voltage supply first.
- Use proper insulation for AC connections.
- Place the sensing wires with corrosion-resistant materials.
- Install the PCB inside a waterproof enclosure near the pump starter.
Applications
- Domestic overhead tank filling.
- Borewell or underground sump monitoring.
- Agricultural irrigation automation.
- Industrial water storage management.
FAQs
Q1. Can I use this circuit for a 1HP pump?
Yes, if your relay is rated for 30A, it can handle most domestic pumps up to 1HP.
Q2. What if I only have an overhead tank, no underground sump?
Simply short the sensing terminals for the underground tank. The circuit will still work.
Q3. Can I run this on 5V relay instead of 12V?
You can, but ensure proper compatibility with the 555 timer output. 12V is more reliable.
Q4. How to protect from dry-run when underground sump is empty?
Add an extra sensor at the sump bottom. The circuit can be modified to cut off pump if sump is dry.
Q5. Is there any delay function in this circuit?
The capacitor and resistors in the timing network provide natural delay to prevent false triggering.
Conclusion
An automatic water pump controller circuit using 555 timer IC is a reliable DIY solution for managing household water levels. It saves time, prevents overflow, and ensures water availability. With a handful of components and a simple PCB assembly, you can build a system that provides both automatic and manual control of your pump.
This project is not just cost-effective but also a great learning exercise for understanding relays, timers, and practical automation circuits.