How to use the Dimlux Maxi Controller

How to Use the Dimlux Maxi Controller


The Maxi Controller is capable of operating and monitoring your Dimlux lighting and CO2 equipment straight out of the box. Add a Dimlux Auxbox and you can regulate fans and the switching of pretty much any piece of grow room equipment, including heaters and humidifiers.

There are two versions of the Maxi Controller – the standard model and a version which features a USB port for data logging, providing you with in-depth information on an array of parameters like temperature, humidity, VPD, lighting output and CO2 concentrations. The more data you’ve got to work with, the easier it is to tweak your settings and get your room dialled in.

Both can handle up to 160 lighting fixtures, daisy-chained from one to the next, which can be split between two different out-ports.

Today, we’re going to talk you through the basic operation; the features that most of our customers tend to use when running one of these systems. The Maxi Controller is capable of a lot, so programming it can seem a little bit intimidating, but actually it’s pretty easy.

First things first, hold down the set button to switch between basic and advanced modes. Switching to advanced will allow you to take advantage of the full range of features.


Each time you hit the button the on left-hand side – the Off / Modus button – you’ll move through a list of options:

  • Lights permanently off and lights permanently on do exactly what you’d expect
  • Lights controlled by timer
  • Lights controlled by countdown – we’ll go into this a bit later in the video
  • Lights controlled as slave invert and…
  • Lights controlled as slave copy, which are used when you’re linking two Maxi Controllers together

Once you’ve found the option that you’re looking for, hit set. For most growers, this is going to be ‘lights control by timer’. We’ll show you how to choose your lighting schedules in a second.

Pressing the escape key allows you to flick through your information displays.

Lighting is the default. It tells you the time, the current room temperature and the time remaining for the lights-on period if you’re using the timer functionality.

The next screen displays information on CO2. To use this, you’ll need to be running a Dimlux CO2 sensor, which measures CO2 concentrations in the air and switches dosing equipment on and off to maintain your chosen level. You can see that level displayed here, along with the actual level in the room.

The next screen is for the Aux Box / Fan controller – a separate piece of equipment that allows you to switch other items of equipment on and off and control fan output rates. It shows the current temperature and fan speed.

The next screen shows VPD levels.

Learn more about VPD here


Pressing set will take you to a settings menu, which will be different depending on the display mode screen you’re on. For example, use the escape button to navigate to the lighting screen, hit set and you’ll be taken to the lighting settings. You can then use the up and down buttons to scroll through a list of options.


In this case, the first option is ‘time’. To set the time, hit the set button again and use the plus and minus buttons to adjust the setting as required.

The next setting up is for the date – pretty self-explanatory

Timer – which regulates switching times for your lights. Choose your on and off times and use the ‘mode’ button to select ‘lights controlled by timer’.

Countdown On / Off – this is an interesting mode that will let you run lighting patterns like 10 hours on / 10 hours off. It doesn’t get used too often, but it’s useful if you’ve only got a limited amount of time to finish a crop. These settings aren’t an option with regular timers because the ‘on’ and ‘off’ times change on a daily basis when you’re running a 20-hour day, but with the Maxi Controller, it’s easy. Once you’ve set this, use the mode button to choose lights controlled by countdown.

Rise / Fall Time

Rise and fall time is often referred to as sunrise / sunset mode. Here you can choose how gradually you want your lighting periods to ease in and out. If you’re using a contactor and timer, your lights will switch on and off quite abruptly, in a way that’s unnatural. By increasing and decreasing output rates slowly, you can mimic natural sunlight. Your plants will react better to gradual changes than sudden shifts. Setting rise and fall times will also help to prevent issues with rot, which can occur when warm air hits cold surfaces.

Temp Limit - One of the big advantages of the Maxi Controller is the ability to automatically dim your lights when temperatures get to levels that affect plant growth, and turn your lights off altogether for safety reasons if temperatures get too high. The first setting tells the Maxi Controller when to start dimming. The second setting tells the Maxi Controller to switch off any lights that are connected to ports 2 and 4. This allows you to switch half of your lighting off to keep temperatures in range. The third setting is the safety setting that is used to switch lighting off altogether if heat levels get into the critical zone, giving you peace of mind.

Temperature Offset allows you to calibrate your temperature sensor to put it in line with your other equipment.

Output Power is used to choose the type of lighting system that you intend to use your Maxi Controller with, whether it’s a single or double CDM, or a 600w or 1000w HPS unit.

Half force mode is for alternating between lights to save 50% on energy, which can work really well in larger rooms.

After Power Fail is pretty self-explanatory in that it tells the Maxi what to do after a power outage. Generally, you’ll want to keep this set to ‘continue’, so that your lights kick back in.

This controls the LED backlight to either stay on permanently or automatically switch off when not in use.

On this screen, you can choose between Celsius and Fahrenheit

Here, you can choose to set the way that output levels are displayed in watts or as a percentage.

And finally, as the name suggests, ‘dual room mode’ is for running two rooms at the same time, so that, light periods alternate from room to room.

If you've any more questions about using the Maxi Controller in your setup, give us a call, pop in store or read our blog on Creating the perfect Environment with the Maxi Controller.

Happy Growing!

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