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

[b4tn]

Did u have it default open or closed?

For the heater is was default open. So if reefpi lost connection or power the heater would turn off.

 

[AquaRaider44]

Normally closed would have prevented the tank from going too cold as relay would fail closed and heater would continue to function based off it's own temp sensor

 

[b4tn]

Normally closed would have prevented the tank from going too cold as relay would fail closed and heater would continue to function based off it's own temp sensor

It’s kind of a toss up which way to wire it. I did it NO so that the heater would stay on if I disconnect reefpi. But then there is it not heating the tank if the relay fails. I will have to re think my relay set up.

 

[sergifed91]

I'm going the pi route. If I'm going to be automating my skimmer, circulation pumps, heater and sbreef lights how many pi's do I need to do this?

 

[Bigtrout]

It was a 250watt eheim beaver

So the heater drew 2.1 amps give or take and those relays are rated for 10 amps resistive load...this is what scares me about the 8 to 10 dollar relay boards...which I am changing in my build to a name brand industrial relays.
I have solid state controlled heaters(aquaeon pro) but I run mine normally closed so that the heater does the control and reef pi is the failsafe.
You have the relays working the heater which has them clicking on and off more often. But according to the songle relay specs (blue relays used on all these relay boards)they should be good for at least 100,000 operations at 2 amps.
Do the math:
100,000 divided by 1440 minutes in a day =only 70 days if the heater switches on and off every minute.

You get what you pay for and I cant trust my tank to hinge on a few .35 cent relays.
A similar rated mini industrial name brand relay like an idec, phoenix contact, allen bradley is rated for a few orders more magnitude of operational life. The phoenix contact relays I will be using are rated at 20,000,000 operations at 2 amps. Of course they cost more, but my main goal for reef pi is functionality and RELIABILITY. Being an electrician and cnc service engineer, I cant bring myself to trust 35 cent relays for something as critical as heaters.
That being said, 100,000 operations is a good long life for something that switches on and off only a few times a day.

 

[Ranjib]

Whichever way works out better for your connections. You can have up to 128 devices on a single i2c bus.
As you add more than one device on i2c, just keep an eye on the pull up resistors on each device. Ideally you will need to remove/jumper on all but one of the devices.
Actually I think the raspberry pi has internal pull ups on the i2c, so you may be able to remove them from all devices. @Ranjib are these set in hardware on the board, or do we have to call them in software?

All that being said, I have not removed them from my devices (and most people probably havent either) and I have not had an issue. But I am only running a single PCA9685 on the i2c bus.

All on hardware . We don’t configure any pull up or down resistor from software

 

[Ranjib]

I just confirmed the relay for the heater outlet failed. All the other relays work just fine. To be honest it does not surprise me and I kind of expected it since I am using reefpi to control the heater. I am going to go ahead and trim my heater up and let it control the switching for now and leave it on the spare outlet until I can replace the relay board. But this may be my excuse to change the heater relay to solid state. Just for everyone’s info these are the relays I got.

https://www.amazon.com/dp/B00LW2GA5Y/ref=cm_sw_r_sms_c_api_i_wDJYCbTDFGBS4

The heater relay lasted about 3 months switching on and off all day. My interval is set to 60 seconds

This is very informative. Thank you for sharing. What was the heater rating ? Like in wattage

 

[Ranjib]

This is very informative. Thank you for sharing. What was the heater rating ? Like in wattage

Oops , sorry I noticed you answered this already.

 

[Zippyfear]

I'm going the pi route. If I'm going to be automating my skimmer, circulation pumps, heater and sbreef lights how many pi's do I need to do this?

It’s kind of a toss up which way to wire it. I did it NO so that the heater would stay on if I disconnect reefpi. But then there is it not heating the tank if the relay fails. I will have to re think my relay set up.

After reading this, I think my strategy will be a primary heater with the built in thermostat, with the system to turn it off if the tank temp crosses above 81 degrees, and a secondary heater switched off, only to switch on(controlled) to provide additional heat below 80.. as of today, both heaters were running with their built in thermostat and all 3 probes have run between 80.6 and 80.8 all day.

What's everyone else doing to maintain temp? and what temp ranges do you keep?

 

[Bigtrout]

I'm going the pi route. If I'm going to be automating my skimmer, circulation pumps, heater and sbreef lights how many pi's do I need to do this?

Depends on how many channels of lighting and how many outlets. A typical reef pi setup with one pi following the guides can handle 8 power outlets and 16 pwm channels for lighting and ato. Adding a second uln 2803 will get you 4 additional outlets and leave a few gpio for inlets.

But I think a new feature being added to 3.0 is being able to control a cluster of reef pi with one main reef pi, which would give you alot of expansion room.

 

[Bigtrout]

After reading this, I think my strategy will be a primary heater with the built in thermostat, with the system to turn it off if the tank temp crosses above 81 degrees, and a secondary heater switched off, only to switch on(controlled) to provide additional heat below 80.. as of today, both heaters were running with their built in thermostat and all 3 probes have run between 80.6 and 80.8 all day.

What's everyone else doing to maintain temp? and what temp ranges do you keep?

I use my heaters set at 78 with their own thermostats, to maintain 78 degrees. I have 2 heaters at 250w in a 75 gallon freshwater planted tank. If one heater tstat fails in off position, the second can handle the tank. Reef pi is set up so that each heater has its own control. They are wired NC and set at 80. If my heater tstat sticks ON, the tank gets to 80 and reef pi opens the circuit to prevent boiled fish. If reef pi fails, the heaters still run on their own thermostat thru the NC relays.
Can you tell i have had a few failed heater deaths? I like redundancy with the heaters!!

Speaking about redundancy, my reef pi setup on my heaters has been reliable enough that im giving my inkbird controller , that i used to use as a failsafe,to a young neighbor whos just starting into the hobby with a 30 gallon freshwater. With my plant jungle that I cull every 2 weeks he will have a good start on a planted tank with the plants I thin from my tank.

 

[sergifed91]

Depends on how many channels of lighting and how many outlets. A typical reef pi setup with one pi following the guides can handle 8 power outlets and 16 pwm channels for lighting and ato. Adding a second uln 2803 will get you 4 additional outlets and leave a few gpio for inlets.

But I think a new feature being added to 3.0 is being able to control a cluster of reef pi with one main reef pi, which would give you alot of expansion room.[/QUOTE
I'll be running 2 wave pumps, each li light has blues and LEDs whites. 2 sbreefs lights. A heater, and a skimmer. I thought my hob filter but I think that will remain plugged in to my wall outlet. Since that is just house cheeto only. Total of 8 outlets. But will add a ph gauge and eventually a tampeture. Maybe monitor par down the road. But for now 2 wave makers, skimmer and 2 sbreef lights. With 2 c hffanneks one for blues and one for whites.

 

[Bigtrout]

One reef pi should do all you ask, with the exception of reading PAR...thats not a feature on the radar as far as i know.

If you are good with soldering, the adafruit guide is a great project. If not, or you want a good shortcut read up on the fantastic reef pi hats that were designed by a few on here. @Michael Lane @wykat and @theatrus all make a great hat, though there are different features to each, depending on what you want to do.

 

[b4tn]

Do the math:
100,000 divided by 1440 minutes in a day =only 70 days if the heater switches on and off every minute.

@Bigtrout Interesting. And it just happens to be very close to 70 days since it was put into operation . I have moved the heater to a NC outlet and am using the heater to control the temp as of now. I also have an aqeon pro now that’s going to be put into the system as a fail safe.

 

[Bigtrout]

@Bigtrout Interesting. And it just happens to be very close to 70 days since it was put into operation . I have moved the heater to a NC outlet and am using the heater to control the temp as of now. I also have an aqeon pro now that’s going to be put into the system as a fail safe.

My aqueon pro heaters are great, with room temp varying 5 degrees, they keep the aquarium at 78 and only vary .3 degrees at most.

 

[sergifed91]

One reef pi should do all you ask, with the exception of reading PAR...thats not a feature on the radar as far as i know

As far as par that will be down the road. Not a priority. The programming should be pretty forward. For the skimmer and heater. On and off for the skimmer. Heated. Turn on at 78 off at 79. Not sure what I'm going to program the Jabea pump and the 1000k gyro yet. If it will just be off and on or get fancy with the code. Since they have there own controllers. Lights will be a little more difficult with programming them.

 

[Ryan115]

Depends on how many channels of lighting and how many outlets. A typical reef pi setup with one pi following the guides can handle 8 power outlets and 16 pwm channels for lighting and ato. Adding a second uln 2803 will get you 4 additional outlets and leave a few gpio for inlets.

But I think a new feature being added to 3.0 is being able to control a cluster of reef pi with one main reef pi, which would give you alot of expansion room.

With some recent updates, I think this may be a low estimate. I believe as of 2.3 we have the ability to use the PCA9685 pins as output pins, though I dont know if we can have multiple PCA9685 devices yet. With those changes, you can control hundreds of outlets and lights while leaving your GPIO pins for inputs.
So 1 pi can do an amazing amount of control.

 

[Zippyfear]

My aqueon pro heaters are great, with room temp varying 5 degrees, they keep the aquarium at 78 and only vary .3 degrees at most.

With heater thermostats maintaining the temp so well, what's the point of using the Reef-pi to control day to day? I see it more as a safety off switch in case the heaters get stuck on. and an alert if they aren't keeping up (assuming one or both fail unnoticed)

 

[Bigtrout]

With heater thermostats maintaining the temp so well, what's the point of using the Reef-pi to control day to day? I see it more as a safety off switch in case the heaters get stuck on. and an alert if they aren't keeping up (assuming one or both fail unnoticed)

First off, WELCOME to Reef2reef!

Thats what its doing in my setup, its my failsafe, not my control...but the monitoring, and email alerts if something goes amiss are invaluable.
Aqueon Pro heaters have solid state controls, other brands have a bi-metal tstat and may not be near as accurate so reef pi may be more accurate. Any heater should have a failsafe of some kind whether its reef pi, an inkbird, an apex. Why trust hundreds in livestock to a 50 dollar heater, or a system with no failsafe if a control fails?

 

[b4tn]

So far switching to heater control with reef-pi as a fail safe my fluctuation in temp is +/- .5. (between 78 and 78.5) I have not put my Aqueon online yet so thats using the ehiem bi-metal heater. I can say when I had reef-pi doing the control, checking every minute, my temp was always within .1 degree of my target. I kind of like that stability and would much rather have reef-pi do the control. I may however change my mind once the solid state Aqueon is my primary heater.

In the meantime I am re designing my power strip. I am thinking to do a mix of solid state and mechanical relays. For the heater relay I think instead of going with a Chinese ebay-special high current solid state relay I am going to go with this Panasonic zero cross 15 amp relay
https://www.arrow.com/en/products/aqa211vl/panasonic

- My ATO uses a toms aqualifter pump which does not like SSR's so it will be a mechanical relay
- Return I want to run normally closed so that will be a mechanical relay
- Wavemakers turn on and off every hour so I will use solid state
- Skimmer, scrubber, and sump light rarley switch so I could use mechanical or SS.

So I am looking at probably doing 4 solid state relays and 4 mechanical.