# 3 phase induction motor speed and direction control by arduino

#### Seka

Joined Jan 11, 2016
1
Hi, I am new here. I am doing a project in controlling the speed and direction of 3 phase induction motor using arduino. I have an idea. But I need to know is it possible to control using arduino. I am messed up with this?

#### clintk

Joined Jan 8, 2017
3
Hello

Im also looking at a similar project but havnt had much luck. I can find plenty of examples and videos of people who have done it
but no diagrams or code etc to try make my own circuits or buy something already out there

#### ClassOfZero

Joined Dec 28, 2016
114
Variable Frequency Drive with a modbus interface.

#### Sensacell

Joined Jun 19, 2012
3,102
An arduino is probably not a good choice for this project.
There are better micro-controller chips that have built in hardware to facilitate driving motors.

#### clintk

Joined Jan 8, 2017
3
Sorry if im hijacking the authors thread

What Im looking for is very basic and VFD are too pricey for my what i need.
Basically I need to take 230vac from mains power supply to drive the 3 phase motor
What I need to be able to do is start the motor and when needed to stop relatively fast but without
a hard brake (ie half speed after 1sec then stop)

The idea behind the arduino is to take simple user input and to tell the motor what needs to happen through the circuit
My idea was to use the arduino to control the speed/ frequency of the motor so I could have say 3 different speeds (can be fixed)

#### KeepItSimpleStupid

Joined Mar 4, 2014
5,088

#### ClassOfZero

Joined Dec 28, 2016
114
I don't think you'll have too much success with an arduino "plug & play" solution.

In my opinion unless you really know what you are doing I'd suggest to stay away from the voltages involved......well that's the route I took. All in all I feel that in the long run a VFD with turn out to be a more cost effective, reliable & safer solution.

Arduino isn't the answer to everything, despite all the hype. Don't take that as knocking the product, as a entry level learning tool they are probably good, but I feel there's too much copy & paste going on. I'll stop with my "Old Man's" rant and go shout at some clouds.

#### tcmtech

Joined Nov 4, 2013
2,867
What Im looking for is very basic and VFD are too pricey for my what i need.
Basically I need to take 230vac from mains power supply to drive the 3 phase motor
What I need to be able to do is start the motor and when needed to stop relatively fast but without
a hard brake (ie half speed after 1sec then stop)
I guarantee you won't build one for less than you can buy one. The 240 VAC to DC to three phase power circuit alone is going to cost you more than you can buy a complete off the shelf unit for.

Especially given a good used VFD's are pretty cheap and plentiful. I've acquired many 1 - 5 HP capacity units for less than $50. Some for under$10 and a few just for removing them from their original applications because the machinery they were a part of was being scrapped.

#### ClassOfZero

Joined Dec 28, 2016
114
I guarantee you won't build one for less than you can buy one. The 240 VAC to DC to three phase power circuit alone is going to cost you more than you can buy a complete off the shelf unit for.

Especially given a good used VFD's are pretty cheap and plentiful. I've acquired many 1 - 5 HP capacity units for less than $50. Some for under$10 and a few just for removing them from their original applications because the machinery they were a part of was being scrapped.

Damn you're one lucky guy.

#### tcmtech

Joined Nov 4, 2013
2,867
Damn you're one lucky guy.
Yea, eBay is really selective on who they sell things to.

Same with the local scrap and salvage yards and electronics recyclers.

#### clintk

Joined Jan 8, 2017
3
yes ideally a 2-3 HP setup for $30 or less is perfect where to get it is the issue I did find the following: 3-Phase AC Motor Control with V/Hz Speed Closed Loop Using the Freescale Semiconductor 56F800/E This chip matched to some capacitors and heatsinks etc can work the the arduino just controlling the inputs but i cant find any for sale so Im guessing its an end of line product #### MaxHeadRoom Joined Jul 18, 2013 26,347 You need a large bridge rectifier and equally large capacitor bank as well as numerous semi's and power Mosfet's. By the time you have purchased parts and built it it is hardly competitive with the cheap Chinese versions, Huanyang etc. of around$100.00
You can set 3 preset speeds if needed, also they have their version of Modbus where RS232/485 can be used.
A DC T.M. motor and controller is another alternative.
Max.

#### drc_567

Joined Dec 29, 2008
1,156
Assuming that issues involving speed control and braking could be resolved, just change the rotational direction of the motor by switching two of the line phase connections. Use an appropriate center-off three pole switch, or possibly a pair of suitably rated three pole relays ... on-off for one direction, and on-off for the reverse direction.
A reasonable delay between direction change would be required, depending on the specific application.

#### tcmtech

Joined Nov 4, 2013
2,867
yes ideally a 2-3 HP setup for $30 or less is perfect where to get it is the issue eBay.$50 - 60 will get you choice of over a dozen that fit that power rating right now.

Otherwise as I said before start scrounging your local salvage yards and electronics recyclers if you want one for less.

Guaranteed you won't build one for less. Especially for \$30.

#### shteii01

Joined Feb 19, 2010
4,644
I don't think you'll have too much success with an arduino "plug & play" solution.

In my opinion unless you really know what you are doing I'd suggest to stay away from the voltages involved......well that's the route I took. All in all I feel that in the long run a VFD with turn out to be a more cost effective, reliable & safer solution.

Arduino isn't the answer to everything, despite all the hype. Don't take that as knocking the product, as a entry level learning tool they are probably good, but I feel there's too much copy & paste going on. I'll stop with my "Old Man's" rant and go shout at some clouds.
I did a little googling. There is a thread on Arduino forums talking about commercial 100 USD VFD that takes 5 volt control signals. Arduino Uno, which is 5 volt system, would be well suited for such VFD. VFD does the motor operation and Uno does the control.

#### ClassOfZero

Joined Dec 28, 2016
114
Yeah but you still need a VFD, I've got a VFD waiting to be installed that takes control signals......Take your pick of MCU and you have control. Nothing special about using an Arduino. In the model I have using a mcu just adds another level of complexity.

Meh if people want to use an Arduino to add complexity I'm not one to stop 'em.

#### dygr

Joined Feb 16, 2018
1