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

[sfgabe]

Is it best to keep them separate? Or will a standard 12volt motor act differently and be fine at a 1000Hz PWM frequency?

Should be fine. I am more worried about the doser circuit causing voltage ripple in light circuit. Test it out and see what happens,

There is definitely some interference, not sure if it's a "ripple" or what. I have the PCA9685 running a kessil and also going to a L298N Motor Drive driving a 12v doser pump. If I turn the pump on while the light is on there is some random brightness and color flickering. It's just a top off so it's not a big deal for me to just run it at night. Easier than diagnosing the problem. :)

 

[b4tn]

There is definitely some interference, not sure if it's a "ripple" or what. I have the PCA9685 running a kessil and also going to a L298N Motor Drive driving a 12v doser pumps. If I turn the pump on while the light is on there is some random brightness and color flickering. It's just a top off so it's not a big deal for me to just run it at night. Easier than diagnosing the problem. :)

@sfgabe thanks for the input! I decided to keep things as is an run the dosers from the built in PWM and lights from the PCA9685. I will post back results once I get it all put together.

 

[sfgabe]

I've been sending commands and getting data to/from reef-pi via the API (from/to Home Assistant) for about a month now and I have to say it works flawlessly @Ranjib. Fantastic job on that!

One question though - is there a way to disable the cookie expiration? It seems like I'm getting about two weeks before I have to update the auth code by logging in and capturing a new one manually. I'm not super worried about security since it's only LAN anyway.

 

[b4tn]

There is definitely some interference, not sure if it's a "ripple" or what. I have the PCA9685 running a kessil and also going to a L298N Motor Drive driving a 12v doser pump. If I turn the pump on while the light is on there is some random brightness and color flickering. It's just a top off so it's not a big deal for me to just run it at night. Easier than diagnosing the problem. :)

@sfgabe Reading through the specs of the PCA9685 board there is a spot on the board for a capacitor if you are running motors to help with power dips. The documentation gives a general formula for servos (number of servos * 100uf). I bought a PCA9685 on amazon that already has a capacitor on the board but I would have to look at the value. I wonder if its as simple as adding a cap to fix the flickering?

 

[sfgabe]

@sfgabe Reading through the specs of the PCA9685 board there is a spot on the board for a capacitor if you are running motors to help with power dips. The documentation gives a general formula for servos (number of servos * 100uf). I bought a PCA9685 on amazon that already has a capacitor on the board but I would have to look at the value. I wonder if its as simple as adding a cap to fix the flickering?

I think I have that amazon one. It looks like the capacitor is 1000uf so theoretically that would cover it, but it still flickers. They are on separate power circuits too, so the only place they could be bumping into each other is through the PCA9685.

 

[Ranjib]

I've been sending commands and getting data to/from reef-pi via the API (from/to Home Assistant) for about a month now and I have to say it works flawlessly @Ranjib. Fantastic job on that!

One question though - is there a way to disable the cookie expiration? It seems like I'm getting about two weeks before I have to update the auth code by logging in and capturing a new one manually. I'm not super worried about security since it's only LAN anyway.

Can you file a github issue, this is something I have to check offline, with the code, and unless its tracked there.. i might just forget/lost it here :-).
Is it possible to recreate the session every week, or so ,, as part of your code ?

 

[Ranjib]

I think I have that amazon one. It looks like the capacitor is 1000uf so theoretically that would cover it, but it still flickers. They are on separate power circuits too, so the only place they could be bumping into each other is through the PCA9685.

I have not tinkered with this yet, but I think we need multiple capacitors, and in multiple places, right before the 10V is fed in to the npn transistors, the 5v input to pca9685 etc

 

[Ranjib]

@sfgabe Reading through the specs of the PCA9685 board there is a spot on the board for a capacitor if you are running motors to help with power dips. The documentation gives a general formula for servos (number of servos * 100uf). I bought a PCA9685 on amazon that already has a capacitor on the board but I would have to look at the value. I wonder if its as simple as adding a cap to fix the flickering?

I think that cap is useful only when you are powering the motors directly from pca9685 (using the onboard +ve pins for each pwm channel)

 

[Ryan115]

On its way...thanks for the heads up.
Now I can stop bringing my Weller Station home from work every time I need it.

Well maybe not on its way. Turns out it was posted from a hacked account. It was not a legitimate listing, it was pulled and I was refunded.
It was too good to be true, but now I really want one.

 

[Diamond1]

Well maybe not on its way. Turns out it was posted from a hacked account. It was not a legitimate listing, it was pulled and I was refunded.
It was too good to be true, but now I really want one.

@Ryan115 I got this one from Ebay. It's only a couple dollars more than the one you ordered and it works really well.
https://www.ebay.com/itm/GAOYUE-936...e=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

 

[Ryan115]

@Ryan115 I got this one from Ebay. It's only a couple dollars more than the one you ordered and it works really well.
https://www.ebay.com/itm/GAOYUE-936-110V-SMD-Electric-Soldering-Station-Solder-Iron-Welding-Kit-W-4-Tips/371505966012?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

Thanks. I'll check that one out. I really liked the hot air, and bench top power supply built into the other.

 

[Fish Fan]

Hi guys! I'm fairly certain that when the build guides first came out the power controller was built using several regular duplex outlets in a typical junction box. Now, I see the build guide has been added over at Adafruit, and has been updated and suggests using a rather expensive (I thought) controllable power strip. What was the reason for this change?

Thanks guys!

-FishFan

 

[ScottBrew]

Hi guys! I'm fairly certain that when the build guides first came out the power controller was built using several regular duplex outlets in a typical junction box. Now, I see the build guide has been added over at Adafruit, and has been updated and suggests using a rather expensive (I thought) controllable power strip. What was the reason for this change?

Thanks guys!

-FishFan

Really isn't that expensive once you consider the parts needed to build your own. Box, relays, outlets, etc. Plus, it's ready to go, no fabrication. I built my own but if doing it again might consider just buying the ADJ.

 

[Ryan115]

Really isn't that expensive once you consider the parts needed to build your own. Box, relays, outlets, etc. Plus, it's ready to go, no fabrication. I built my own but if doing it again might consider just buying the ADJ.

As @ScottBrew said, it gives a ready to go option.
Also wiring the 110V is the most dangerous part of this build, and many people were hesitant to go that route themselves.

I am happy with the old UPS that I rewired for relays, but I would probably go with the ADJ option rather than building one from scratch if I was doing another one.

 

[b4tn]

Hi guys! I'm fairly certain that when the build guides first came out the power controller was built using several regular duplex outlets in a typical junction box. Now, I see the build guide has been added over at Adafruit, and has been updated and suggests using a rather expensive (I thought) controllable power strip. What was the reason for this change?

Thanks guys!

-FishFan

I just finished wiring up my power box tonight. I was originally going to go with the pre made strip which does have the advantage of being easy and safe if you are not comfortable wiring yourself but I wanted the ability to have several relays wired so they where on while power is off and some that are only when triggered. I have also never done any 110 wiring so I wanted the challenge and the chance to learn something new :)

 

[Fish Fan]

Hi guys! Wow, thanks for all the replies! I figured it was a safety thing. For me, I'd prefer to do it the "old fashioned way" as I already have the materials to do so (duplex outlets, relay boards, box etc. ). Even if I didn't have the parts already, it wouldn't cost anywhere near the $50 for the American DJ power strip, so for that reason alone I think I'll just go the previous method and wire the receptacles myself. I do have some experience with the wiring, I just used an Raspberry Pi with an 8 channel relay and 120AC to control a Halloween light/music show. But I wanted to ask to make sure I wasn't missing something.

Thanks again everyone!

-FF

 

[ScottBrew]

Hi guys! Wow, thanks for all the replies! I figured it was a safety thing. For me, I'd prefer to do it the "old fashioned way" as I already have the materials to do so (duplex outlets, relay boards, box etc. ). Even if I didn't have the parts already, it wouldn't cost anywhere near the $50 for the American DJ power strip, so for that reason alone I think I'll just go the previous method and wire the receptacles myself. I do have some experience with the wiring, I just used an Raspberry Pi with an 8 channel relay and 120AC to control a Halloween light/music show. But I wanted to ask to make sure I wasn't missing something.

Thanks again everyone!

-FF

The biggest advantage to the DIY power module is being able to use solid state relays, the ADJ has mechanical relays. IMO, not a problem with stuff that is on all the time like main pump, skimmer, so on but my powerheads are on and off regularly as well as the heater. 2 downfalls to the solid state is they don't have a normally closed position AND most are only rated for 2 amps. I ran an 8 channel solid state but am going to change it to a 4 channel solid state and a 4 channel mechanical setup. Mainly so the main pump can be hooked up to normally closed as a failsafe.

 

[Fish Fan]

^ I have used the mechanical relays in the past, and for my reef tank build I was going to go with solid state only because I think they will be quieter. Thanks for the help!

-FF

 

[Ryan115]

^ I have used the mechanical relays in the past, and for my reef tank build I was going to go with solid state only because I think they will be quieter. Thanks for the help!

-FF

Depending on the size of your heater, if you have a chiller or if you are running MHs, you may want a few mechanical relays. The typical 2A limit on the SSRs is something to keep in mind.
Also the NC setting on them is really nice.
If for some reason reef-pi goes down, I can still have my return pump running and the heater reverts to running on its own thermostat.

 

[Ryan115]

So back to thermometers again...
The GFCI on my tank just tripped, and after some quick panicked troubleshooting, it was traced back to my DS18B20 thermometer.
I purchased these years ago on ebay, but they were the typical "stainless" coated ones in a cheap 5 pack.
I had coated this one in silicone months ago, and (I though) everything was going well. Turns out there was a small uncoated spot the finally rusted through. I could see it arcing in the water when I plugged the unit into a non-GCFI outlet.

Anyway, I am on the hunt now for a new one, but it looks like the black epoxy canakit ones are sold out everywhere.
Has anyone sourced either the epoxy ones, or better stainless ones anywhere?
Or what other products have people coated theirs with? I have more of the original ones, that could be re-coated.