Here is the issue. The motor controller has ‘soft stop’ on it.
Since I am playing with chatgpt
chatgpt: A motor soft stop refers to a gradual and controlled
deceleration of a motor’s speed before coming to a complete stop. It is
achieved by gradually reducing the voltage or current supplied to the motor,
allowing it to slow down smoothly without abrupt changes. This helps to
minimize stress and wear on the motor and connected equipment, preventing
sudden stops that could cause damage.
OK thanks Sean-O- in that case i have a different motor speed controler i could try and see if it brakes motor speed faster- OTHERWISE- how can I or any body tell how soft start or soft stop a pwm motor controler might be–ARE you saying i might find a fast enough stop motor control’er to stop the wire in time---- or is there a dc motor control’er that has soft enough start that i can use the relay i bought to short and unshort the motor. OR can you show me one for sale that is what i need or is this all just possible ideas=
You can test with disconnecting the wires after speed controller, before motor, when motor is running, if it stops faster, if it still runs a couple of rev’s through “living momentum” in motor armature, it probably needs a “brake” as mentioned before.
This are seldom built-in in universal speed controllers, but a need in welding machines, because motors don’t stall immediately, exactly the same as some windshield wiper motors, if the shorting/brake mechanism is broken, the wipers slowly stop, somewhere “right in sight” or catch up their “auto parking” steady voltage, and just continue running.
Kevin i would check the document for the controller you bought it seems like this should be a setting to control the soft stop speed. Soft starts are very common to limit max inrush current but soft stop isnt that common a thing in my experience with motion controls. So i suspect there is either a dipswitch of software setting. There also might be a output for when in motion which you could use as a relay control output.
Sean and i were thinking i need a time delay too slow start the motor so that the shorting relay-or normally closed relay has more time in like probbley ms to unshort the motor before it is powered up with power supply. I caint seem to find time delay relay in ms time around 15-20 amps 24 dc volts- i think i need to build a simpler ms or 10th of second type of a short time delay-too the motor. THIS IS REALLY mostley confusing me— I see delay circuits on utube- i might try building one from there- AND with all these wire feeders for mig welders on line- i see no wire feed motor controlers for welders- just a million or so pwm regular dc motor controlers. THERE might be good money in building a wire feed type adjustable motor stop- motor controlers- I bought a shorting relay so i might be able to slow the start timeng of the motor enough i have no heating problems,? SEE WHAT HAPPENS I GESS. skin this wire feed control’er later. Time too go hook up my gas lines for wood truck ,and get some fans on it- allmost done with dakota cab corners repair and gasifier- truck still need brake and gasoline lines plummed up to my new tank. and truck needs paint job. Back too work for now most all welding is done for now. I bet matt rider might know what delay timer to use, or a simpler way to control the motor brake short- since he is into all the automation systems.
I would -try- to run a motor and let it spin fast, then flip the switch on the controller. to brake and see what happens. It may reverse the current and lock the motor. If that is the case, then unsoldering the switch and putting relays or transistors to act as the switch is the easiest thing to do. I couldn’t find a description for the switches.
They have 4 mosfets on it, so you would -think- it is an hbridge configuration, but if it is why it doesn’t have reverse I do not know.
there is also a version of that board where they aren’t advertising soft start/stop.
After that, it is a dynamic brake configuration. which looks kind of like this. Where M and B are sets of relays. Then you have to spec a brake resistor out based on your motor specs. Running the motor M is closed, B is open, and it is reversed for braking.
Thanks for the skidmatic-I keep that in mind while while testing for delay times if wire burns back in the tip or runs too far out after shut off switch knob. WHAT control the mosfets timing is what i caint see how it would hook in.
You would control it with the trigger switch. so you pull the trigger and the relay acts like it is in the ‘run’ position on the board, you let go of the switch and it is in the brake position. you have to know what the pins are active for each position in the switch.
I would have to think about a delay for the brake. It is approaching the point where I would just be using a microcontroller, an h-bridge (or that board and removing the microcontroller on it), a couple of rheostats and just programming it.
ITS out of my knowlege realm- Ware you get all your electronic circuit knowlege from. I wish i had the brain for all the ity bity detail circuit know how or not how. what you think it would cost in parts to build a 15 too 20 amp at the load- too install micro control’er / h bbridge and reostat for my parts setup. the more adjustments the better unit it would be- for all the varios types of wire and other variables. I have the pwm i posted motor control’er.
WITH all the shortages of mig welder wire feed control’er–you might make a lot of money- posting them on amizon or ebay-- reader too plug intoo all those wire feed units on line- with no wire stick out adjustment available. I supose i would be happy to get a good heavy duty 15 amp controler- 100.00 $ or little more. would sell like hot cakes.//////////////// all the 500 too 1200 half ass one roller wire feed mass production machines- brake down OR start slipping wire- right and left- would be more than happy to find a good wire feed adjustable brake motor controler.
Hi Sean , can you teach an old dog a new trick , where in the link that Kevin posted on the motor controller does it say it has a soft stop , i looked and looked but my old eyes cant make that out , i always miss stuff like that when buying replacement parts and end up buying another till i get it right .
Dave
HY sean o i posted a pic of my snapon ya212 mig welder wire feed circuit from the book or on line manuals. Can you see any sort of a brake circuit in skidmatic. The power to motor was 24 dc volts.THANKS THAT circuit lasted a good many years- so it must be a good one-Simple Delay Timer Circuits Explained | Homemade Circuit Projects
The power to the board is AC there is a bridge rectifier in the upper left corner with 4 diodes in a diamond shape. that converts ac to dc for the rest of the board.
The old board if it doesn’t work, it would probably be easiest to just repair it. 75% of bad electronics, it is the capacitors that are bad. And about 90% of the time, you can visibly see they have expanded somehow, and are bad. But just doing them all is the easiest. just mark with a sharpie what direction they are as some of the capacitors have a +/- legs to them and the boards are marked wrong. Sometimes the variable resistor flakes out especially in dirty environments and sometimes the bridge rectifier diodes flake out, but usually they discolor when they overheat.
The last circuit with the 555 is called a ‘one shot’ and you can use a variable resistor as the resistor, but variable capacitors are insanely expensive.
THANKS for all the incite with / about circuit boards/delay/relays-ect. I will see what i can find on my circuit board- that sounds possible, as soon as my truck is out the shop in working i will plug the motor back into the original board and do better trouble shooting- and check the board out better- see what went-- i think i seen the bigger round flat unit expanded or melted- not for sure- but it did look like it had melted slittly. while i was taking things apart i found a loose main wire going too one of the big cables- probbly caused the over heat fail. THANKS MUCH for the support learning about the circuit- I check back later when i see what else i can learn.
