3 Phase Motor Programmable on and Off Controller
With a programmable time, switch, you can make a 3-phase motor controller that automatically turns on and off. In this case, you can only set up to eight-time durations. The system has tw…
Know the mission before touching a wire.
Understand what you are making, prepare the right tools, and make the workbench safe.
Project details
3 Phase Motor Programmable on and Off Controller is a electronics project. With a programmable time, switch, you can make a 3-phase motor controller that automatically turns on and off. In this case, you can only set up to eight-time durations. The system has tw…
- Source pages
- 317-319
- Named parts
- 2
- Build goal
- Working, tested prototype
Tools you need
- Digital multimeter
- Wire stripper and side cutters
- Soldering iron with a fine tip
- Current-limited bench supply
Use eye protection, good lighting, and a clean insulated surface throughout the build.
Safety precautions
- Disconnect every power source before changing a connection.
- Check component polarity, pinout, and supply voltage twice.
- Use a current limit for the first power-up.
- This project may involve hazardous voltage. Work only with qualified supervision and proper isolation.
Gather, identify, and understand every part.
Use the standardized inventory, then open What's this? to learn each part's role, advantages, limitations, handling, and specifications.
What's this?Image, role, pros, cons, handling & specifications
Power supply
A power component supplies, converts, stores, or regulates energy for the project.
What it does hereIt must provide the documented voltage, polarity, isolation, and sufficient current safely.
Buy / compare this part ↗Advantages
- Stable power improves reliability
- Current limiting protects first tests
- Regulation reduces resets and noise
Limitations
- Wrong polarity can cause immediate damage
- Underrated parts overheat
- Mains circuits require qualified supervision
Handling
- Measure output before connection
- Use a fuse or current limit
- Insulate exposed conductors
Specifications to verify
- Use the exact model, value, package, and rating listed for Power supply; similar-looking parts are not always interchangeable.
- Confirm input/output voltage, current, polarity, connector, isolation, and thermal rating.
What's this?Image, role, pros, cons, handling & specifications
Transformer
A power component supplies, converts, stores, or regulates energy for the project.
What it does hereIt must provide the documented voltage, polarity, isolation, and sufficient current safely.
Buy / compare this part ↗Advantages
- Stable power improves reliability
- Current limiting protects first tests
- Regulation reduces resets and noise
Limitations
- Wrong polarity can cause immediate damage
- Underrated parts overheat
- Mains circuits require qualified supervision
Handling
- Measure output before connection
- Use a fuse or current limit
- Insulate exposed conductors
Specifications to verify
- Use the exact model, value, package, and rating listed for Transformer; similar-looking parts are not always interchangeable.
- Confirm input/output voltage, current, polarity, connector, isolation, and thermal rating.
Connect one verified path at a time.
Explore the named components and standardized signal flow, then use Source Check to verify exact physical pins, values, and topology before applying power.
Trace this circuit.
3 Phase Motor Programmable on and Off Controller: interactive parts, standardized terminals, responsive anchored wires, student explanations, and the original circuit reference in one shared system.
Trace before wiring
Follow power, ground, inputs, processing, and outputs in that order. Never guess a pin from package shape alone.
Connect with power off
Make short, labelled connections and share a common ground only where the schematic requires it.
Inspect every joint
Check continuity, polarity, adjacent shorts, and loose connections before the first power-up.
Open all source diagrams and build views 2 visuals
Confirm the hardware-only control path.
This project does not include firmware in the source. The circuit itself provides the required behaviour.
How to connect
- Match every controller label to the circuit view and source pin map.
- Join grounds before signal wires when separate low-voltage supplies are used.
- Keep motors, relays, pumps, and other loads on a suitable driver and external supply.
Common mistakes
Reversed VCC/GND, board-label versus GPIO-number confusion, missing common ground, and charge-only USB cables.
Troubleshoot
Disconnect loads, continuity-test one path at a time, then test with a current limit.
Software preparation
No IDE, board package, library, or firmware upload is required for this project.
If you add a programmable controller as an extension, document its pin map separately.
How to upload code
The original design is implemented entirely in hardware, so proceed after verifying the circuit and supply.
Assemble, deploy, test, and troubleshoot.
Use the complete source notes in build order, then pass the final checks before calling the project finished.
Build in functional stages
- Power and regulation
- Controller or processing stage
- Inputs and sensors
- Outputs and loads
- Enclosure and strain relief
Power up safely
- Inspect unpowered continuity first
- Apply the lowest safe current limit
- Measure supply rails before signals
- Add one load at a time
- Record expected and actual results
Work from simple to complex
- Confirm power, ground, polarity, and orientation
- Compare each pin with the source
- Test inputs separately from outputs
- Replace only one variable at a time
- Power off before every correction
Follow the documented instructions.
These notes come from this project's source and remain in their original order.
Project overview
Project build noteWith a programmable time, switch, you can make a 3-phase motor controller that automatically turns on and off. In this case, you can only set up to eight-time durations. The system has two programmable time switches that can be used to set when the motor will start and stop, as well as two control circuits that are connected to the start and stop switches of the 3-phase motor's starter. Fig. 1 shows a block diagram of the system. Fig. 1: Block diagram of the 3-phase motor programmable controller Let's say that both time switches are set to the same time. So, if 8 a.m. is set as the start time for timer1 ON mode, 8.01 a.m. will be set as the start time for timer1 OFF mode in the start time switch. And if the stop time is set to, say, 9 AM for the timer2 ON mode, then the stop time switch will be set to 9.01 AM for the timer2 OFF mode. When it's 8 a.m., the start time switch connects the primary of transformer X1 to 230V AC. The power supply's output is connected to IC1's reset pin 4. R4 and C3 are parts that turn on by themselves. The monostable's output at pin 3 is high for a time period of 1.1R5C4, which is almost five seconds. 3 phase motor programmable controller circuit
Fig. 2: Circuit diagram of the 3-phase motor programmable controller As long as pin 3 of IC1 is high, relay RL1 is on for five seconds. This shorts the start switch, which lets the 3-phase supply to the motor go for longer. This is almost the same as pressing the 3-phase motor starter's start switch for five seconds. When it's 9 AM, the second time switch (stop switch) sends 230V AC to the primary of transformer X2 from the secondary. Again, 12V DC is sent to the second monostable circuit with relay RL2 by using a full-wave rectifier and filter circuit. The 3-phase motor's stop switch is connected in series with the relay's normally-closed (N/C) terminal. So, the relay stops the motor by breaking the circuit. This is an example of a time span from 8 a.m. to 9 a.m. So, the 3-phase electric motor can be set to turn on and off at one of up to eight different times. There is a way to choose which days of the week the controller will work. It can be set to work Monday through Friday, Monday through Saturday, all seven days of the week, or just one day of the week. This system can be used for many things, like turning on a water pump in a multi-story commercial building only five or six days a week to fill tanks on the roof. It can also be helpful for farmers, factories, or train stations that use 3-phase motors.
Circuit operation As shown in Fig. 2, two power supply circuits are built around transformers X1 and X2 and the other parts that go with them. The setup gives 12V DC to two control circuits built around two monostable 555 timers, IC1 and IC2. Two TM-619-2 time switches made by Frontier are used in this system. These use 230V AC at 50Hz to work. Each switch has a 16A contact single changeover relay built in. It has an LCD screen with buttons like CLOCK, TIMER, DAY, HOUR, MIN, and MANUAL. With these buttons, you can set a real-time clock and program different time lengths. The time switch is a digital device that can be programmed. It has a digital real-time clock and can be set for up to eight different time periods. The times can be for one day, every other day, Monday through Friday, Monday through Saturday, or Monday through Sunday.
You built 3 Phase Motor Programmable on and Off Controller.
You followed the full workflow from understanding the mission to testing the finished project. That is a real engineering achievement - well done.
Digital Frequency Meter Using Arduino
Ready to reuse what you learned in another project from the same track?
Start this project →