I just wired some gavitas to a plc. I couldn’t find a gavita low voltage diagram, so I had to reverse engineer an el1. Just wanted to post what I figured out hoping it will save someone some time. The center 2 pins (red and green wires) on the rj9/rj11 are dc-. The outer pins (yellow and black wires) are dc+. Below 5vdc the lights are off, 5vdc=50%, 10vdc=100%, linear. Max voltage is 11.5v.
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What’s your controller end look like & the wiring on the unit itself?
If it’s the unit i have on my mind it should just be a simple wire twist for dimming sadly… it’s hilarious but yeah…
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I think an Arduino or Raspberry Pi could easily clone one of these if the low voltage wiring was well documented.
China did a quick and affordable spin off of these units, although the interface was terrible.
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My control end is an automation direct domore plc, the gavita phone cords are wired directly to onboard 0-10v analog outputs. I am waiting on some dc boost modules I ordered to boost my 10v to 11.5v. It’s setup in a greenhouse with par meters. The back end is a PID controller in the programming that is set to maintain 1,000 umol.
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Arduino or pi could easily be set up with a 0-10v driver. I’m just comfortable with plc ladder logic and needed a lot more i/o than most pi boards have. I picked this plc up for $100 on ebay, and all automation direct plc’s have free software. The gavita low voltage is incredibly simple, if you have any questions ask away.
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Hi @emdub27! I’m interested in control a Gavita pro e-series from an arduino and the only info about this was your post. I don’t know if you are currently active in this forum or if this message will arribe to you but if it does could you help me on some questions?
The dc- and dc+ pins on rj11 connector (red/green and yellow/black as you said) can be connected to the same dc source or there is one pair of pins for other purposes?
You said that from 5vdc to 10vdc there is a linear dimming from 50% to 100%, for example 7v dc is 70% of power? Then 11v is 110%?
Thank you!
The red and green pins are connected to each other inside the ballast. The yellow and black pins are also connected to each other inside the ballast. One DC voltage source is all that is needed.
Correct 11.0vdc is 110% and 7.0vdc is 70%. In my case I had to use a dc voltage boost module to get above 10vdc.
I have confirmed the same siring and voltages also work for nanolux as long as you buy the usb to rj11 adapter.
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This info is gold!
Thank you so much for your investigation and share with others, very useful!
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So I can make a dimmer for cheap?
Yes you can dimmer a Gavita light with cheap hardware. Also you can do the day/night cycle without any timer, just an arduino that turns on/off the gavita applying more than 5V to the rj11 port.
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Did you use a I2C DAC Module to output that voltage signal?
Also, i noticed the RJ9 from the Gavita EL1 outputs as follow:
Pin 1: -11.5V-0 | Pin 2: GND | Pin 3: GND | Pin 4: 0-11.5V
How did you manage to convert this with a DAC from an arduino or esp board?
Thanks
Im looking to do this as well and curious if you needed a signal isolator\amplifier\conditioner on the output for long strings of lights?