Thread: Steppers continued.

Looking at the circuit that you have I would expect that the '-ve' pulse terminal should be connected to the '-ve' on the 555 not the '-ve 12V'.

Eureka, it goes! Managed to get the stepper moving one step at a time, this is the schematic I used with dip 1 and 2 on and 3 off. Now, how do I get the stepper to rotate continuously, I've tried all the Dip positions to no avail.

I tried changing the jumper on the other other set of posts - success, continual rotation. There is a fairly long pause before the motor starts spinning, annoying, but I can work around that. Is there another driver board I can use, preferably with a speed control, so I can place the driver and generator in the same enclosure.

I may need two systems I guess as there will be occasions when I'll need to move both carriage and cross feed at the same time. so I'm thinking of one driver and generator to drive carriage and tailstock and another pair to drive cross and compound slides.

These are fun things to play with, I'll have to think of something else I can adapt them to.

Excellent!

The PUL+ and PUL- are at each end of an optocoupler therefore if you connect the Ne555 output to PUL + you need to ground PUL-.
EN+ and EN-, DIR+ and DIR- are also on each end of an optocoupler so if you put 5v on one end you need to ground the other.

As you have found out, you don’t need to connect EN+ or EN-. Your connection is the same as the diagram I posted earlier.

You can change direction by connecting DIR- to GND then connection DIR + to 5v. Remove the 5v from DIR+, and it will go back to the original rotation direction.

Bugger, blew the generator. Not watching what I was doing I connected positive to negative.

What are the EN connections for?

If you make it High ie. EN+ to 5v and EN- to GND, you can turn the steppper by hand when it is not being pulsed. When EN is not connected (Low), the stepper is locked in position when not being stepped.

Great, I'll need that connection when I set everything up.

I can fix your generator if you want

Originally Posted by Deanus

I can fix your generator if you want

And maybe add a fuse/breaker as well.
That's usually one of the the first things I add to test circuits.

I had a look under a loupe and couldn't see any burnt bits, I assume it's the 555 Ic that has blown, usually the first that that goes, I wouldn't like to try replacing the surface mount resistors, so darn small now. I just ordered four generators for $1 each, amazing the price of these things from China and another couple with speed and direction control. I visited Jaycar this morning and bought some three pin sockets so hopefully I won't do the same again. I'll need to get a smaller driver though so I can mount driver and generator in a jiffy box so i can get them them out of the way.
Any recommendations for a driver, must be at least 2 amp?

sacc51.....if you need any assistance feel free to contact me, i am at Aldinga beach

Small units like the MP6500, A4988, DRV8825 etc have adjustable current control and are good to about 1.8 to 2A per phase. They are very small but some have peculiarities eg. some you can leave vacant pins floating while on others they have to be tied High or Low. You need to carefully read the instruction sheets - see Pololu site for good info.
I’m buying a lot of my gear from Littlebirds as it’s only 2km away - it’s cheaper overseas but I like the convenience and the ability to talk to someone.
I’m also currently building a box with a 12v to 5v convertor, NE555 generator systema and a A4988 driver inside.
I have it all working great with an Arduino eg ClockWise button, Stop button, CounterClockwise button and speed control but I would like it in a small boxr - I may try an Arduino Nano clone see what I have now works?

The Arduinos are cheap and very easy to program for what you want to do but it’s a larger package.

As mentioned in my previous post, I have full control of my stepper motor now in regards to speed, rotational direction and start and stop. I am, as the title suggested, using an Arduino. This will be the basis of my router lift stepper motor setup although I will be using a rotary encoder rather than a potentiometer so I can position the router height. When I have the prototype up and running, I will post it on the Router Forum.

Thanks to saccs1 for inspiring me to delve deeper into the world of steppers (I sincerely mean it)

Heres a short video of my set-up.
https://youtu.be/scrBBHxxXCw