Aquaculture + garage automation - which relay board to use?


#1

How you doing guys? Im new to the raspberry pi b+ but I’m intrigued for sure. I raise tilapia in a recirculation system. Im looking to control a pump/motor , 4 valves, 2 lights and an lcd touch screen for now. I will be adding PH, DO,and temp sensors later on. I Will be using a 32 inch flatscreen for part of the garage audio/music.

I have the raspberry pi b+ running wheezy, I have a 13.5 max power supply thats about it for the pi components.

Which type of relay board would support a 10 amp 1.5 hp motor?

any help is appreciated!


#2

I designed a relay board with (4) 20A/277Vac relays, -with (8) analog inputs for the Pi 26 pin GPIO. That would work perfectly.
http://community.mydevices.com/t/4-277vac-16a-relays-ps-8-analog-sensor-inputs-on-a-pi-hat-kit/987?source_topic_id=985


#3

I would love to take a look at that. thank you!


#7

thanks man, a lot of help. I’ll check on those!


#8

A little dusty. I JUST now took the pictures-


#9

Awesome, that would work great for the big pump!


#13

Ya. Also, you won’t need a big power supply. Any ol’ power supply that can deliver between 7.5 volts and +24Vdc @ 1000mA (min) will work-
and the hat also powers the Pi, so you only need one power supply.
I use old HP printer power bricks
because I have so many.
19Vdc is okay.

Each relay draws something like 80mA,
so all 4 relays, picked, would draw 320mA.
The MCP3008 only draws something like 150mA
The Pi only draws about 400mA (unless its doin’ video).

The relays are rated to 277VAC @ 16A- PLENTY of power!
Legally, an electrician can only LOAD 80% of a circuit breaker rating, so a 16A relay would be appropriate for a 20A fused circuit. :wink:

-you can get all the parts delivered in 2 days if you’re in a rush…
It takes about 1 hour to solder it all together


#15

I’m actually an electrician , but I’m looking to move into more of the engineering side. This looks awesome man I really appreciate the help.


#17

its alright man, you have gave me plenty to think about.


#19

Hi @JoshG502,

Welcome to the Cayenne community! Thanks @HighTech for sharing your expertise :slight_smile:

@JoshG502 Cayenne is great for projects like your recirculation system. I would switch from Wheezy to Jessie, Raspberry Pi foundation no longer is releasing updates for Wheezy, and we (Cayenne) stopped officially supporting Wheezy too. If you’re familiar with Arduino, we’ve just released support for Arduino as well.
http://community.mydevices.com/t/about-the-arduino-beta-category/810?source_topic_id=985


#20

@JoshG502 I’m going to move this topic to the Helped category, hope you don’t mind :slight_smile:


#21

This circuit was originally designed for
4 1000 watt IR illuminators,
-and 4 motion detectors,
-and 2 long range IR beams,
-and a tamper switch
-and a power monitor…
for a remote security system.


#22

Thanks High tech, Ive started on the shelving systems and work benches in the garage. Getting the screens put up now and the speaker systems. Gonna be nice!


#23

I already tested/used the 4 relay setup in the field- so I know it works perfectly- the only problem is- because it’s a Pi2/Pi3 footprint, the yield is only (3) units per PC board order- a bit low, and the low yield makes it a BIT more expensive.

The PC boards cost $68 for 3 boards using the “cheap” Miniboard service, and for that price, the boards MUST measure 2.5" X 3.8"…

So, I just used the “extra” space on the PC board for the Charlette 2X4 (also tested/good). So, your yield would be (3) Brute 4X8 boards + (3) Charlette 2X4 boards. The Charlette relays are only rated for 3 amps- so…be aware. Those relays would be good for electric valves.

AND, you can get the electronics parts MUCH cheaper if you buy from Amazon or eBay- I have a “special” deal goin’ on with DigiKey, so I use them for the parts list/sourcing. :wink: Keep in touch!


#24

Kewl- using the analog inputs, a 10K variable potentiometer between 3.3V and ground, -you would have a digital input volume control, too. I don’t know how to program for that- but I DO know it’s been done…the ADC generates a 10 bit number (from 0 to 1023).