reef-pi :: An opensource reef tank controller based on Raspberry Pi.
- Thread starter Ranjib
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No. There is plan to add a tasmota driver. I have to first get a compatible device first .
The 8825 is a good standard driver that isnt overly priced. I have 3d printers and used about all the drivers out there. but dont need the fancy stuff that the higher end drives offer like stall protection thats used for sensorless homing. I can breadboard up a demo and even design a pcb for controlling the drives. I just dont know coding. you write code I can design the circuit and test it. I wonder if the pca9685 can be used to output the pulses to control a stepper.
These are boards with multiple relays and pins ready for the pi. They were cheap but I was following a guide. I am more than willing to get some quality relays, but lack the technical knowledge to know what to get. Can you reccomend some or provide a resource?
I have been using tmc2209 on my 3D printer and dosing pumps for awhile. They’re a lot quieter than the pololu drivers and support UART, so they’re very easy to configure (eg you can set the motor current programmatically rather than with a potentiometer).
can you send me a pic? and do you know how to solder? it sounds like the relays arc welded. and once it starts it continues. what was the amp rating on the relay? most are 2 amp. also what is the power draw on the item plugged into it?
with 4988 or 8825 you can hard wire everything and control the stepper with just a single line pulse. (need a common ground but that wont be an exclusive pin, so not taking up a pin.) so would use 1 pin per doser pump. but wonder if a pca9685 could be used for the pulses to the driver? not to mention that 4988 are $1.60-$180 each and 8825 are $2 each on amazon. might be cheaper on aliexppress but the wait. 2209 are $6 each. and i dont think the noise will be that bad as dosers shouldnt run that much. and most aquariums arent that silent so would cover most of the noise.
does uart control steps and everything? I just thought it controlled the settings. but still used the old standards for enable direction and and step? if 2 pins control everything then that would be the way to go. is 4 drivers a hard limit or just what youre using? most printers use 4 drivers while some use 5. (dual z in my case not wired in series or parralle had 6 drivers so used 5 on a fysec f6) Ive never looked into how printer boards work just compiled the marlin. but have looked into controling steppers, and looked at what the pins do on older drivers. also what would be easier to code? 1 wire per dosing pump or serial bus control? also is 2209 uart? or spi? i2c? i know 2208 is 1 and 2209 is the other. think spi and i2c is the sameTrue but with UART its 4 drivers on a 2 pin bus
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Sure thing. I bought an 8 relay unit and a 4 relay unit off Amazon
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Tmc2209 is UART. You can set the speed using the serial interface and it maintains that indefinitely. That’s how I use them. You can address up to 4 drivers on one UART bus by setting address bits on the drivers themselves. They are sophisticated devices. I haven’t explored all their features and maybe there’s a way to address even more. For the noise, I agree with dosing it’s not a big deal. For AWC the steppers move pretty fast and noise becomes an issue. I haven’t tried the 8825, but the a4988 really fills the room when you run it that fast.
ive used that brand before with no issues, but with chinese knock offs who knows if i had real, or if yours are real. I also never used mine with much power it was an amp or 2 of 12v dc. heres a compatible part ( https://www.digikey.com/en/products...er-brumfield-relays/ORWH-SH-105D1F000/4925028 ) from a repitable supplier, but the cost it might be worth buying another and hoping it was just a fluke.
well my thing is I think I would need atleast 8 if not 9 dosers for everything. I dont know if pi has multiple uart pins. and the number of dosers needed is why i was wondering if pca9685 could be used to deliever the pulses. each 9685 has 16 output and can be chained together to give massive number of outputs using just i2c. and If i design a board it can have 48 output easy, which should be more than enough for dosers and anything else that the and the pwm powers the doser, the faster the pwm the faster the doser doses, but think the pi uses 1 pwm for everything, so not sure how it works on that side, or how to limit the number of pulses.
Those aren't too bad. Only way I would want to just rebuild is if any of the issue may be due to the
Is there muxh chance any part of the board would cause it? That would be an argument to rebuild. Otherwise the digikey relays aren't very expensive.
if its sticking till you tap it its arc welded. the tap breaks the weak weld. but once it arc welds, it builds carbon, and then then it becomes more prone to arc due to increased resistance from the carbon causing it circle and get worse. i was looking at 8 port you bought for $9 where the digikey are $12 for just the relays plus shipping.
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