Create the Perfect Growroom Environment with the Dimlux Maxi Controller

With a fully automated Dimlux lighting system, you can let the Maxi Controller take care of regulating up to 160 lighting fixtures (and practically every other piece of equipment in your grow room) all from a central point! The Maxi Controller comes with an array of features that reduce your workload while maintaining an optimal environment with pinpoint accuracy. Replicating your plants’ natural conditions as closely as possible is the key to getting great results, and regardless of whether you’re looking at temperature, humidity, CO2 levels, or even VPD (vapour pressure deficit), the Maxi Controller has it covered.

Here’s a quick rundown of some key features:


Contactors and timers have served us well over the years, allowing us to control the switching of power-hungry HID lighting reliably and safely. But this simple switching technology doesn’t allow much room for additional functionality. In a professional Dimlux set-up, every lighting fixture in the room is connected directly to a mains outlet and powered continuously. Dimlux fixtures are instead ‘told’ when to emit light, and at what intensity, via data cables that connect to the Maxi Controller. This development opens the door up to an array of features.

There are numerous add-ons that can be purchased for the Maxi Controller, but the most important starting point is the temperature sensor. With access to temperature info, you can program your lighting to adjust to environmental conditions, running at the greatest output levels that they possibly can without pushing temps too high. If the room gets too hot, leaf stomata close up in order to conserve water. This prevents plants from utilising CO2, slowing down photosynthesis, stunting plant growth and reducing potential yields (we'll talk about this more later on). It may seem like a backwards step to reduce lighting output, but it will keep your garden running much more productively. If temperatures creep above your chosen safety cut-off point, then the Maxi Controller will automatically shut down all lighting ,  reducing the likelihood of encountering a catastrophic issue. This gives you peace of mind when leaving your grow room for prolonged periods.

‘Rise / Fall’ mode is a feature that eases plants in and out of daytime and night-time stages, reducing stress while lowering power consumption. Not only that, this feature also minimises the likelihood of encountering botrytis (rot). One of the biggest causes of Botrytis is condensation, which occurs as warm air hits cold surfaces. If lighting switches on instantaneously, there's a period where the air temperature rises before plant materials have had time to warm up, putting your grow at risk. ‘Rise / Fall’ eliminates this problem by warming your plants and the surrounding air gradually. You can select exactly how gradual you wish to make the transition by choosing the duration of the sunrise and sunset.

Heaters & Humidifiers

The Aux Box pushes the Maxi Controller to the next level by allowing you to programme the switching of other items of grow room equipment (not just Dimlux lighting and accessories). Connect the Aux Box’s power cable to a mains socket and plug the data cable into the Maxi Controller; then you can plug equipment into the sockets on the face of the Aux Box. Heaters, humidifiers and dehumidifiers can be switched on and off when needed by using the data gathered from the Maxi Controller’s sensors, keeping your environmental conditions optimal at all times. And unlike most regular thermostats, you can select different parameters for daytime and night-time stages. Your plants have different needs at different stages of the day, so it makes sense to adjust your equipment accordingly. Older equipment never offered you that kind of functionality, but the Maxi Controller makes it easy.

Carbon Dioxide (CO2)

Connect up a CO2 sensor and regulator, and the Maxi Controller will maintain optimal CO2 concentrations in the air. Dosing is triggered automatically whenever levels in the area fall below a user-defined setting. Getting CO2 levels right is one of the single biggest ways to improve yields once the rest of your environmental conditions are optimal (and with a Dimlux set-up, they definitely will be!). Normal background CO2 levels are generally between 330ppm and 450ppm, but plants can take full advantage of CO2 at levels over 1000ppm. Greater levels of CO2 increase the rate of photosynthesis which massively accelerates plant growth. It’s no exaggeration to say that CO2 supplementation can trigger gains in yields of up to 20%.

Vapour Pressure Deficit

The Dimlux Plant Temperature Camera measures leaf temperatures, allowing you to regulate equipment according to VPD levels. VPD gives you a more accurate picture of the conditions that facilitate peak photosynthesis than simply tracking temperature and humidity. For instance, optimal humidity levels actually vary depending on air temperature and leaf temperature readings. Beginners can work out VPD levels with an infra-red leaf temperature sensor and some simple mathematics, but the Maxi Controller beats this method hands-down by providing you with real-time information.

The ultimate goal of monitoring VPD is to keep stomata, the tiny pores on the surface of leaves that are responsible for gas exchange, open as much as possible, so that plants can absorb CO2  effectively. This CO2 is used to manufacture the sugars that plants need for growth. Increased absorption of CO2 means bigger and better crops!

Shorter Days

Other useful features include ‘countdown mode’, which allows you to create asynchronous lighting schedules that wouldn’t be possible with a typical 24-hour timer. For instance, running a ‘10 hours on / 10 hours off’ flowering cycle can be advantageous in situations where  you need to get your plants finished off as quickly as possible.

Data Logging

Upgrade to a data logging Maxi Controller V1.2 and you can record any information that's gathered and save it to a USB stick, allowing you to fine-tune different aspects of the equipment in your grow room. For example, you may notice from the data that your temperatures are dropping too low during your plants' dark period and decide to increase the size of the heater in the room. Or you may notice, for instance, that your lighting is dimming too often due to excess heat and decide to increase your extraction or invest in an Opticlimate climate control system. Essentially, data logging gives you a much clearer picture of what is going on in your indoor garden, particularly while you're away. You can monitor the following parameters and create overlaid graphs over user-defined timescales, providing clear visualisations of the insights that you need to make positive changes.

Ambient temperature
Plant temperature
Relative humidity
Absolute humidity
CO2 Concentration
Dewpoint temperature
Setpoint temperature low
Setpoint temperature high
Setpoint temperature shutdown
CO2 set-point

When we said that Dimlux have given growers everything they need to create the perfect environment, we really weren't joking! For more information, check out the individual listings at our Dimlux category. And remember that we have an expert team on hand waiting to talk you through your dream set-up, so if you have any questions, contact us on 01782 749955 or email us at

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