If you run an indoor farm, you know this moment. You start with ten lights under the canopy, and tuning them is easy. Then the farm grows to a hundred or two hundred lights, and half your morning goes to walking the rows and turning knobs.
You do not have to. With the right under canopy LED grow light setup, one controller can dim hundreds of lights at once through a simple 0-10V signal and ordinary phone or network cable.
Quick answer: our lights link into short chains with a 30cm plug-in connector. The chains join through a 3-way connector and RJ12 or RJ45 cable to one smart controller. At 120-277V, one chain holds up to 14 lights (120W), 5-7 lights (150W) or 2 lights (250W).
Why Controlling Under Canopy Lights Separately Becomes a Problem
Adjusting under canopy lights one by one works for a handful of fixtures, but not for a growing farm.
The cost of adjusting lights one by one
If it takes 20 seconds to reach and adjust one light, 200 lights take over an hour, every time you change the level. Hand settings also drift. One row ends up brighter than the next, so plants in the same room get different light and good results are harder to repeat.
Why dimming and central control matter
Under canopy lighting works on the lower leaves and inner canopy, and the right level changes with the crop stage and the season. Dimming also saves power: at 70% brightness, an LED light uses roughly 70% of its full power. That is why more farms now manage lighting centrally instead of fixture by fixture.
A growing trend
Greenhouses and indoor farms keep getting larger while labor stays a major cost, so growers want to set light levels for a whole room from one place. Under canopy lighting is now treated as part of the full lighting plan, which means it needs to be dimmed and managed together with the rest of the system.
Two Ways to Dim Under Canopy Grow Lights
Our lights support 0-10V dimming, which you can use with a manual knob or a smart controller.
What 0-10V dimming means
Think of a water tap. The signal does not carry power. It only tells the light how bright to be, from 0 to 10 volts. At 10V the light is at full brightness, and a lower voltage means a dimmer light. Because the signal is separate from the power line, one instruction can reach many lights at once.
Knob or smart controller?
|
Manual dimming knob |
Smart controller |
|
|---|---|---|
|
Best for |
Small rooms, a few chains |
Large rooms, many chains |
|
Lights controlled |
A small group |
Hundreds of lights |
|
How you adjust |
Turn the knob by hand |
Set levels from the controller |
|
Typical user |
Small grow |
Commercial greenhouse, vertical farm |
With a knob, you turn it and every connected light follows. With a smart controller, you set the brightness once for the whole group. Ask us which controller models we supply.
How to Connect Under Canopy Lights Together (Daisy Chain)
To daisy chain under canopy grow lights, plug each light into the next with the 30cm connector that comes with it. There is no cutting, no stripping and no tools.
Plug-and-play with the 30cm connector
Place the lights where you want them.
Push the first light's 30cm connector into the port of the next light.
Repeat until you reach the limit for your model.
The light-to-light connection needs no electrician. How the first light connects to your main power supply follows your local electrical rules, so plan that part with your installer.
How many lights per chain?
At 120-277V:
|
Model |
Power per light |
Lights per chain |
Total per chain |
|---|---|---|---|
|
4ft |
120W |
Up to 14 |
Up to 1,680W |
|
6ft |
150W |
5-7 |
750-1,050W |
|
8ft |
250W |
2 |
500W |
Stay within the limit for your model. If you want to mix sizes or need longer chains, ask us before you build.
RJ12 vs RJ45: Which Port Do You Need?
The dimming signal runs on its own cable and port, separate from the power chain. We can supply either RJ12 or RJ45.
Power and signal are two separate lines
The 30cm connector carries power. The RJ12 or RJ45 port carries the dimming signal. You need both.
Phone cable or network cable?
RJ12 uses phone-style cable. RJ45 uses network (Ethernet) cable, which is sold almost everywhere. Both carry the same dimming signal here. Pick one type for the whole project and tell us which one when you order.
Cable length: keep each run short
For the dimming signal, we recommend keeping each cable run to 3 meters (about 10 feet) or less. When you plan your layout, place neighboring chains so the signal cable between them stays within that distance. If your rooms are wider and you need longer distances, talk to us before you buy cable, and we will suggest a layout that works.
Step-by-Step: Control Hundreds of Lights from One Controller
For how to control multiple grow lights with one controller, the path is: lights, 30cm power chains, a 3-way connector on each chain, RJ12 or RJ45 cable, then the controller.
What you need
Lights with 0-10V dimming and RJ12 or RJ45 ports
The 30cm connectors included with each light
One 3-way connector per chain
RJ12 or RJ45 cable (one type only)
One smart controller
Step 1: Build the power chains
Link lights within your model's limit (14, 5-7 or 2). Start a new chain when one is full.
Step 2: Add a 3-way connector to each chain
It lets a chain pass the dimming signal on to the next chain. Label each chain so you can find it later.
Step 3: Link the chains with cable
Connect the 3-way connectors chain to chain, keeping each run within 3 meters and away from power lines.
Step 4: Connect the controller and test
Start low, raise the level step by step and walk the room. Every row should brighten and dim together. If a chain does not respond, check its cable and 3-way connector first.
FAQ
Q: Can under canopy LED grow lights be dimmed with 0-10V?
A: Yes. You can dim them with a manual knob or a smart controller.
Q: How many under canopy lights can I daisy chain?
A: At 120-277V: up to 14 lights of the 4ft (120W) model, 5-7 of the 6ft (150W) model, or 2 of the 8ft (250W) model.
Q: Do I need an electrician to connect the lights?
A: Not to link the lights to each other, since each has a 30cm plug-in connector. Connecting the first light to your main power supply follows your local electrical rules.
Q: How many lights can one controller control?
A: Hundreds. Join each chain through a 3-way connector, then link the chains with phone or network cable.
Q: What is the difference between double side and triple side under canopy lights?
A: A double side light emits on two sides with a 180° beam angle. A triple side light emits on three sides with a 240°-270° beam angle, covering a wider area.
Q: What is the maximum signal cable length?
A: We recommend keeping each signal cable run within 3 meters (about 10 feet).
Q: Are your under canopy lights waterproof?
A: They are IP66 rated: fully dust-tight and protected against powerful water jets, but not designed to be submerged.
Ready to upgrade your indoor farm with reliable under canopy lighting? Share your room layout, fixture requirements, supply voltage and project quantity with our team. As an under canopy light manufacturer, we provide OEM and ODM services to support custom product specifications and project needs. Contact us to discuss your requirements, request a quote and find the right lighting solution for your operation.
