My business is spitting and rewinding fabric for multiple industries. My oldest machine uses a DC motor (link attached below) with a DC motor controller with on/off and a POTs dial. I bought an Uno Rev3 and a DC motor controller with the addition of an Isolated 0-5 to 0-250VDC / 4-20mA signal follower input. (Link also attached below)
I am working my way through videos on YouTube to figure out how to program my Uno to be able to output a 4-20mA signal to tell my DC motor to ramp up to speed, use a Pulse Rotary Encoder(link attached) to go a programmed distance and then slow to a stop. I am not 100% sure, but I think that I need something(a DAC board?) that will go between the uno and the DC motor controller.
I am very confused about what a “4-20MA DAC MODULE” is and if I need it. It talks about it being a “loop”, but is it almost the thing that outputs the signal to control the DC Motor?
Many thanks for any input or answers to can provide.
Your use case is a motor that is supposed to travel a fixed distance, and the the rotary encoder would give current position as feedback. The Arduino would control the system. Is this correct?
It's not clear at all what You want to achieve, what to do.
Then You step into designs You are guessing about.
Come on! Present the work to be done!
Please provid a logic block diagram showing the process.
More details about parameters to use, what they are like, where they come from, and what kind of output control needed.
My question is whether I need the DAC to produce the mA signal to tell the motor what speed to go or is the Arduino capable of making those signals.
One of the first toptechboy videos I watched on YouTube what about controlling a small DC motor that came in the starter kit. I know that I haven’t even started to scratch the surface of the capabilities of the Uno and didn’t know if it was going to be able to provide the 4-20 mA to the DC controller directly or if I needed the DAC to talk to my controller
It's a 4-20mA loop controller. Not sure if you understand the 4-20mA loop but you can read about them. An Arduino can't generate such a signal directly, hence you need the module. The module is controlled by an I2C interface, so you need to send it I2C commands.
Sorry boss, I am still new to this. I can draw the diagram that I am hoping to get too. The newest machine that I currently run was built in 92 and I am just starting to get into the PLC vernacular and world. I grew up in the slitting/rewinding web converting industry. I am fully versed in spools, rollers, shears and motors…. Not so much the controllers that run them. I wish I had the knowledge with these PLCs so I didn’t have to send them back to the EU to be worked on
Look, I know you made one in your first post, but why don't you take some time to make a more detailed description? For example, a question I'd like an answer to is: Will the motor travel back to it's original position?
It would help to know the model of the machine you are intending to use this with.
Using hobby components in an industrial environment is not really a good idea, an off-the-shelf PLC controller designed for such use would probably be a much better choice.
Not any boss here but You look like aiming over Your head.
Get into the subjects where You have things You can learn. PLC is a great tool and logic knowledhe is valuable. Making it true in the microcontroller world calls for learning the capabilities provided by the microcontrollers.
"Videos on YT" tells nothing. Unfortunately there's a lot of crap out there.
Get closer to the ground to make things sorted out in a good order.
Starting from guessing certain hardware is wrong. Make the block diagram, in Your maind, present it here and start from that point.
The motor controller you linked to has a 4mA to 20mA current loop control input for speed. 4mA to 20mA current loops are standard for control in many applications, but I have never used one, so the advice I can give is limited.
A Uno does not have anything that would produce a 4mA to 20mA current loop control output. In order to get the control output you need a digital to analogue converter (DAC) with a 20mA current loop output. I've never looked for such a thing but I imagine they exist. The DF Robot device you linked to does not say it has a 20mA current loop output, but some othe devices on the Digikey page do, for example:
I'm not clear about the MIKROE 1296, but the RAK5801 has an I2C interface, which is available on a Uno so it should be possible to get it to work with a Uno. I don't know how easy this would be, and more to the point I don't know how easy (or difficult) it would be for you to get it working.
A "20ma current loop" (or presumably a 4-20mA current loops) is a control signal for (mostly older) machinery. It doesn't directly drive the motor any more than the PWM Servo signal directly drives the motor in a servo (but it has similar function.)
Using a current loop make control "more immune" to cabling issues, and it's pretty noise resistant.
For instance, early teletype terminals used a 20mA current loop before rs232 became popular.
You definitely need some sort of converter to drive (or receive) such a loop on an Arduino. The voltages involved can be quite substantial (to overcome long wire runs with high resistance, and/or variable loading at the "destination"), especially compared to modern electronics.
I bought an Uno Rev3 and a DC motor controller with the addition of an Isolated 0-5 to 0-250VDC / 4-20mA signal follower input
I don't think I understand your overall setup. It might be possible to replace your "historical" hardware with a more modern motor controller that doesn't need the 4-20mA loop converter. Motor control is a thing that has had a lot of relatively recent technological advances. A lot depends on the actual motor involved, and probably on local "code." A 90V 1/2HP motor is a different beast than most of us are used to dealing with. (OTOH, not too far off of what's might be used in (exercise) treadmills, eBikes and eScooters. A while ago, 90VDC treadmill motors with showing up on the surplus market at very low prices.)
(and a lot of DC motor applications are now using 3phase "brushless" motors, with "slightly fancier" controllers.)