reef-pi :: An opensource reef tank controller based on Raspberry Pi.

[ScottBrew]

Two days minimum up into the mountains! Amazon says Sunday-Tues package deliveries.

Here's hoping for 2 days then!

 

[rushbattle]

Tell that to the three "Same Day" packages Amazon Logistics has lost in the past two weeks for me, where the other couriers have been flawless :)

Right! I wish for Fedex every time I order. My mail carrier is quite good as well, but overall USPS performance depends on where the package gets handed over. UPS isn't bad here either. But all the couriers have their bad days...

 

[theatrus]

Right, absolute best is not absolute :)
"To the best of your knowledge, what is the best stepper powered persitaltic pump for dosing ~50-400ml per day very accurately and precisely and has very high reliability with low maintenance required relatively speaking" is what I should have said. I have a bad habit of just assuming that others know what I am thinking. I am sorry I wasn't clear, I appreciate everyone's time and effort and I hate to be disrespectful by not being clear!

Thanks for your help, greatly appreciated!

Compared to the DC motor pumps, I think either of these steppers is much better. Why?

• The DC motor pumps have a friction fit set of rollers in the center of the motor shaft. This will slip, be inconsistent, etc
• There is no guarantee the motor will make a set number of turns - different loading (head height, debris from kalk, etc) could easily cause different rotation speeds.

The stepper pumps both have the rollers attached to the D shaped stepper shaft and can't slip. Its still possible to miss a step if you try to run the stepper too fast or the tubing is truly clogged, but the average performance should be a lot better.

 

[Ranjib]

I have seen it posted up here before, but I have forgotten now. What is the absolute best quality peristaltic pump head and motor combo that runs at 12V or less? DC or stepper are fine, I guess stepper would be slightly preferred. Anybody know what Vertex used in their dosing unit? I thought those heads looked pretty solid. I'll give them a test with the motor HAT after I do my 0-10V analog signal (pump control) testing.

Take a look at atlas scientific for reference, they are very accurate. Masterflex is also very reputed in the local reef community .

 

[Ranjib]

New toy today! Whole lot better than my 15 year old 40 watt Radio Shack iron.

Hope to get my pump controller working tomorrow, i2c or pwm, decisions, decisions...

https://www.droking.com/dc-5v-36v-p...drive-module-electronically-controlled-switch
https://www.amazon.com/gp/product/B00SK8MBXI/ref=oh_aui_detailpage_o01_s01?ie=UTF8&psc=1

That is so so so much better. My wife gave it S Christmas gift last year. Best gift ever.

 

[ScottBrew]

Tell that to the three "Same Day" packages Amazon Logistics has lost in the past two weeks for me, where the other couriers have been flawless :)

Can't say I've had that much bad luck with them. Had many a priority 1 overnight packages from Fedex be delayed and get stuck sitting in a hotel an extra day or 3. Here's how the package USPS delivered yesterday from BRS arrived.

 

[Ranjib]

Take a look at atlas scientific for reference, they are very accurate. Masterflex is also very reputed in the local reef community .

And yes definitely stepper if you want better precision. I think I can get away with two parts and ato with dc motor based peristaltic pumps, but for very precise small doses like magnesium or alk or if we want to build a general purpose titration feature , the definitely stepper motors

 

[speedstar]

That is so so so much better. My wife gave it S Christmas gift last year. Best gift ever.

speaking of soldering wish these 50 y/o eyes luck tomorrow soldering up a ph/orp board. Was no problem in my younger years, but my eyes have been getting worse

 

[speedstar]

Can't say I've had that much bad luck with them. Had many a priority 1 overnight packages from Fedex be delayed and get stuck sitting in a hotel an extra day or 3. Here's how the package USPS delivered yesterday from BRS arrived.

almost all my BRS packages have looked like that, I am always scared to ship bulbs with other stuff. My test kits have been beat so bad when tossed in with salt buckets loose.

 

[rushbattle]

Compared to the DC motor pumps, I think either of these steppers is much better. Why?

• The DC motor pumps have a friction fit set of rollers in the center of the motor shaft. This will slip, be inconsistent, etc
• There is no guarantee the motor will make a set number of turns - different loading (head height, debris from kalk, etc) could easily cause different rotation speeds.

The stepper pumps both have the rollers attached to the D shaped stepper shaft and can't slip. Its still possible to miss a step if you try to run the stepper too fast or the tubing is truly clogged, but the average performance should be a lot better.

The Kamoer looks the part! Thanks! I will order a few and let you know how my testing goes. In agreement on the stepper vs DC motors. My company sells (very large in comparison) permanent magnet motors and we use a somewhat similar comparison to induction motors, but the slip is in between the rotor and stator, not at the coupling to the pump!

 

[ScottBrew]

speaking of soldering wish these 50 y/o eyes luck tomorrow soldering up a ph/orp board. Was no problem in my younger years, but my eyes have been getting worse

TRUTH! I've lost my magnifying visor, was looking for it when I assembled my reef-pi.

 

[Ryan115]

And yes definitely stepper if you want better precision. I think I can get away with two parts and ato with dc motor based peristaltic pumps, but for very precise small doses like magnesium or alk or if we want to build a general purpose titration feature , the definitely stepper motors

Agreed, stepper motor is definitely the way to go for precision
I did just get one of these little guys in the other day https://www.amazon.com/gp/product/B00VHYO9F0/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
It is a step up from the other friction stepper motors. The motor shaft has a gear press-fit onto it that drives teeth on the rollers.
I ran it at 5V and pinched the tubing and it had enough power to pull lots of cavitation bubbles in the tubing.
@5V ran about 300mm/min.

Also picked up one of these https://www.amazon.com/gp/product/B0744FWNFR/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1.
Pushes more water at 5V than an aqualifter ~1000+ml/min. Doesnt run on airline tubing though,

 

[That Crusso Kid]

The Kamoer looks the part! Thanks! I will order a few and let you know how my testing goes. In agreement on the stepper vs DC motors. My company sells (very large in comparison) permanent magnet motors and we use a somewhat similar comparison to induction motors, but the slip is in between the rotor and stator, not at the coupling to the pump!

@rushbattle - these look to be the same pump but at a lower price point.

https://app.alibaba.com/dynamiclink...share_detail&ck=share_detail&shareScene=buyer

 

[b4tn]

On the topic of stepper motors. I did a quick read on them and think I get the basics of how they work. Does reef-pi have the ability to control one though? Or is that in a coming release?

 

[theatrus]

On the topic of stepper motors. I did a quick read on them and think I get the basics of how they work. Does reef-pi have the ability to control one though? Or is that in a coming release?

Directly? No. But you can use PWM or other mechanisms to drive the STEP input on a driver.

 

[b4tn]

Directly? No. But you can use PWM or other mechanisms to drive the STEP input on a driver.

So if I am understanding correctly to use reef-pi to control steppers you would need the driver like a tb6612, 4 GPIO pins and 2 PWM pins?

https://learn.adafruit.com/adafruit-tb6612-h-bridge-dc-stepper-motor-driver-breakout/pinouts

 

[Ranjib]

So if I am understanding correctly to use reef-pi to control steppers you would need the driver like a tb6612, 4 GPIO pins and 2 PWM pins?

https://learn.adafruit.com/adafruit-tb6612-h-bridge-dc-stepper-motor-driver-breakout/pinouts

currently yes, can be 16 pins also (if you are using pca9685, the guide uses rpi but thats not a strict requirement). I am looking forward to the outcomes from first round of stepper motor based experiments, we can certainly add more software features if needed.

 

[LionHeart2017]

currently yes, can be 16 pins also (if you are using pca9685, the guide uses rpi but thats not a strict requirement). I am looking forward to the outcomes from first round of stepper motor based experiments, we can certainly add more software features if needed.

I'm thinking if you could add water monitoring ultrasonic distance sensor hc-sr04 and things like rain drop water detection modules, for ato water level notification/monitoring, leak detection alarm etc

 

[Ranjib]

I'm thinking if you could add water monitoring ultrasonic distance sensor hc-sr04 and things like rain drop water detection modules, for ato water level notification/monitoring, leak detection alarm etc

I think leak detection can be done by using a leak detector sensor and just using it as ato. They work in same fashion.

 

[Ryan115]

I'm thinking if you could add water monitoring ultrasonic distance sensor hc-sr04 and things like rain drop water detection modules, for ato water level notification/monitoring, leak detection alarm etc

I was wondering about something like this for monitoring the levels of you reservoirs. Alternativly could reef-pi keep track of the amount of each dosing/top off and subtract it from a user input starting amount?