DMX - Setting up 3rd party dimmer

[Dieter Lessmann]

I am trying to set up a 3rd party 12ch DMX dimmer but not getting anywhere.

Just a little history.... I have bought a couple loxone products to test and familiarize myself with for a new build I am starting this year.

To keep costs down my idea is to use the tree extension with touch pure as inputs and dim all the lighting using the dmx extension and 3rd party dmx dimmers.

The loxone config is proving a lot more complicated than I had imagined and I am able to connect and set up the tree devices and dmx devices but switching anything on/off seems to be more than I can manage at the moment. When "learning" the device the lights switch on so everything is connected properly but I don't how how to set it up so I can control the channels. Also with 12 channels how do I control 4 different sets of RGB's for example as it only lets me set up one set?

If only there was a youtube video that explained how the loxone config worked..... Is anyone able to help or point me in the right direction?

[Duncan]

with non-loxone dmx dimmers you cant 'learn' them in, you need to add the dmx devices manually - start by deleting any learn or auto added dmx devices apart from the dmx extension

the 12ch dimmer has 12 sequencial channels with a starting number (lets assume its ch1 in this case)

to add your 4 x rgb dimmers, you manually add 'dmx rgb actuator' which will add a single device in the loxone config which has 3 channels -you will need to adjust the starting channel for each rgb group, so the first will have a ch number 1, 2nd will be 4, 3rd is 7 and 4th is 10

you then attach your rgb actuators to your lighting controller and change the output type to rgb - thats it!

[Dieter Lessmann]

Thanks Duncan

When adding "dmx rgb actuator" I get a "smart actuator" listed under my DMX device under the periphery tab and not 3 channels?

[Duncan]

the smart bit doesnt really matter

what matters is the  channel number a few lines above which is the first channel of the 3channel group in the case of an rgb actuator

a dmx decoder can be a smart actuator - this adds some features when using a light controller v2, including that the fade rate can be adjusted automatically by the lighting controller but you cant manually adjust it

a standard actuator has a fixed fade rate which you can set according to your needs - the dmx fade rate is visble if you select the dmx subdevice and is % per second - 100 is 100% fade over 1 second, 10% would take 10 seconds to fade from full to off

[Dieter Lessmann]

On your screenprint I can't see what channel numbers you are referring too, is it the bit under "Preferences"?

I have Channel number = 1 under my preferences tab.

I've also now changed the actuator type from "smart" to "standard", is that correct?

[Duncan]

yes channel number is the first item under preferences

if you are using v2 of the light controller then you may wish to keep your dmx devices as 'smart' so the light controller can adjust the fade time dynamically to blend in other scenes, do rgb colour change sequences etc

'standard' actuator will lose some of the functionality offered with v2 of the lighting controller although it gives you fixed control of the fade rate - have a play and see which you prefer once you have the basic rgb dimming working ok

[Dieter Lessmann]

sorry to be such a pest, as this is the first and only DMX dimmer attached at the moment the channel no. is 1.

The confusion for me is that if I "add a DMX device" and select "DMX RGB actuator" I only get one "DMX device" showing under peripheries. This is fine for the first 3 channels on the dimmer to control the first rgb led strip but how to I then add and control the other 3 rgb led strips? The ones that are connected to channel (4,5,6) and (7,8,9) and (10,11,12)

Do I set up a new device for each set of channels for each led strip connected to the same dimmer? That would make more sense as one set of 3 could be used for rgb and another for 3 channels of white only strips, all within the same physical dmx dimmer box

[Duncan]

your 12ch dimmer has 12 separate dimming channels, numbered in sequence from the starting dmx address (in your case 1, so your devices are channels 1-12)

you can connect any of the 12 outputs to anything that can be dimmed ie white strips, rgb, rgbw etc but the order you physically connect the outputs needs to be reflected in the order you create the dmx devices in loxone

your first rgb device in loxone uses 3 channels and starts with ch1, so for each further rgb device you need to create another dmx rgb actuator - lets say 2nd rgb device comes next and starts with ch4 so it uses 4,5 and 6. 3rd rgb that you add to the config needs to start at ch7 and uses 7,8 and 9

now if you want to control some single white strips (lets say 3 separately) you add 3 'dmx actuator' which are single channel devices in the loxone world - each shows up as a separate dmx device and would be assigned the channel numbers 10, 11 and 12 - each of these single channels can be dropped onto your config/lighting blocks and appears in the controls as a separate dimmable device

[Dieter Lessmann]

That makes perfect sense and is very logical, embarrassingly so. Sometimes one can overthink things...

I think I was getting there as I was writing my last response to you but you have explained it so clearly you should really contribute to the loxone documentation.

Thank you so much for your time Duncan, very much appreciated. Muchas Gracias!

[Duncan]

glad you got it sorted

the main thing about dmx is that its fundamentally a 1-way only system and loxone doesnt really know anything about whats out there listening to the messages: it could be a single physical dimmer, or 10 dimmers set to the same channel number so they all react together at the same time to the values been sent out, or hunreds of different type of devices. (an exception is that loxone can search for and identify its own dmx dimmers, probably using RDM, and auto create them in a config file for you)

loxone's own dmx extension can only use 128 channels, where as a single dmx universe (a single cable/network) can have 512 channels normally, so if you need more than 128 channels you would require 2 or more dmx drivers and split the system using separate dmx cables - each dmx cable would have devices using channels 1-128 because they are separate systems and loxone's dmx extension cannot use addresses above 128.

dmx is supposed to be a single linear network/cable with the controller at one end, looping through each dmx decoder/driver and terminated at the far end, buts its possible to have a multi-branched dmx network using dmx splitters, which pass packets along to a number of separate branches, each of which will require a terminator at the end

there are a few things that loxone 'knows' about and treats as a single device, such as a single dimmable light channel or an rgb light using 3 channels and it tries to present these in the UI as something sensible, but there are plenty of things it doesnt obviously know about such as rgbw light strips or relays

loxone basically sends a message which is a dim value from 0-255 for each channel, although it is scaled to a 0-100% interface within the config and app

certain non-dimmable devices such as dmx relays get exactly the same messages, but they are usually built so that something like a 'dim' value of 128 or higher turns the relay on and a value lower than this turns it off. loxone hasnt get a clue whats going on, so for certain devices you have to introduce some workarounds eg multiplying a 1 (on signal for a relay) by 100 to make sure a relay gets a high enough signal to actually turn on

[Dieter Lessmann]

You are right about using DMX for relay switching. I quickly realised that this would be a cheap way to add more outputs but with only 128 addresses it may be limiting, but you say one can have more than 1 DMX Loxone extension?

I'll test it on some external relays next but I can't see why there should be any problem as long as the "light" setting is set to 100% the entire 12v or 24v would pass through to power the relay. I'll measure the output.

[Duncan]

i was talking about specific dmx relays like:

https://www.aliexpress.com/item/32793354973.html?spm=a2g0o.productlist.0.0.5ec13944YqwjZM&algo_pvid=9f1f04ce-ee32-4225-bb5f-6512ae88cbd7&algo_expid=9f1f04ce-ee32-4225-bb5f-6512ae88cbd7-0&btsid=c51d4b67-a955-48bd-8d48-a62c0e1c7cc2&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_53

but you can use dmx dimmers to power normal relays as you suggested, or better still to power SSRs particularly if you are switching led bulbs such as gu10, where the high inrush current often kills normal relays by fusing the contacts

and yes you can add multiple dmx extensions as required

[Dieter Lessmann]

What is the advantage or difference between the DMX relays and the DMX dimmer? I seem to get more channels per £ with the dimmers

I've connected a finder relay to one of the DMX dimmer channels and it switches it no problem but there is that "fade in" period that sounds like the relay is being sucked in instead of being switched. Is there a way to fix this?

In the lighting controller settings I've tried to change the smart actuator to a switch from the drop down list but it doesn't work then...

[Duncan]

the advantage of the dmx relays is just removal of the extra wiring requirements between a dimmer and the relay (the low voltage stuff) - functionally its the same

to get the relays to switch cleanly and quickly you need to get your dimmers to switch from 0 to 100% as quick as possible to provide the relay with the full required changeover voltage.

to do this you need to set the dmx output so that a '1' or on gets sent out to the dmx dimmer as 100% and this is achieved using a few minor adjustments to the dmx dimmer channel driving the relay:

set the type from smart to standard

set the fade rate to 'jump'

set the correction to input 1 is 0, target 1 is 0 and input 2 is 1, target 2 is 100

that way a on/logic1 at the dmx input is immediately converted to a 100% fully on output

[Dieter Lessmann]

Makes sense but as they are rated 4A I assumed they would drive an external 10A relay but really I'll leave that to the electrician to advise me. I'll look into getting din mountable versions of those.

Thanks for the switching advice, I've changed the fade rate to "jump" and it clicks over as expected.

[Duncan]

the current from the dimmers to drive the 10A relays will be only a few 10s of milliamps - the heavy current is then through the contacts of the relay, but be aware that if you are switching leds on and off with a relay the inrush current when the leds switch on can be massive, eg 80x the nominal on current

so for example a string of 10x 5w gu10 leds has a nominal 50w at 240v which is 0.2A but the inrush could be 16-17A which after a few 10s or 100s of on/off cycles may well fuse the relay contacts together

to avoid this its best to use SSRs driven by the dmx dimmers instead of mechanical relays - most of these have a lowish current rating, but include a zero crossing switching circuit which avoids the inrush current - so a 2A SSR with zero crossing can quite easily switch 20x or more 5W GU10s without any problems