| Log in

VMBDMI-R - Single channel triac dimmer for resistive and inductive loads

1-channel 400W dimmer, suited for incandescent lamps and certain LED lamps.
(For best results with mains LED lamps, we advise the VMB4DC with a universal 0-10V dimmer.)


  • Only a qualified professional may carry out the installation in conformity with in force legislation and standards.

  • protocol manuals for developers

    available for download at https://github.com/velbus

  • leading edge dimmer
  • suited for: incandescent bulbs, halogen lamps on AC, low-voltage halogen lamps in combination with dimmable wire-wound iron core
  • soft turn on / off extends bulb life
  • thermal protection
  • switches off with too inductive loads (feature can be disabled for use with dimmable LED lamps)
  • 250 possible addresses
  • operating modes:
    • dimming
    • slow on / off
    • timer
    • multi level dimmer
    • moods
  • turn off time: from 1 s to 3 days
  • dimming speed: from 2 s to 23 h
  • dimming from 0 until 100 % in 4 s
  • minimum level can be preset
  • built-in not resettable fuse
  • AC power: 220 - 240 V 50 Hz
  • max. load: 400 W
  • minimum load: 40W (if necessary add an electronic preload)
  • thermal protection:
    • > 80 °C to 25 % light intensity
    • > 90 °C to 0 % light intensity
  • power supply: 15±3VDC
  • dimensions: 90 x 36 x 58 mm
  • width: DIN 2 modules
  • consumption: 30 mA
  • fuse: 4A slow, 5x20mm


PDF-File Short manual


PDF-File Dimming with Velbus
Overview of the possibilities of dimming various types of lighting with Velbus
EXE-File VelbusLink 10.8.1 (EN/NL/FR) - Latest version
Free Windows program to configure and program a Velbus installation (latest version - 05/19/2022)
PDF-File Velbus Installation Guide, Part 1: Hardware and Cabling
Everything you need to know about the Velbus hardware
PDF-File Velbus Installation Guide, Part 2: Configuration
How to configure Velbus modules using the free software VelbusLink
PDF-File Velbus Troubleshooting Guide
Step-by-step guide for solving Velbus problems.
EXE-File VelbusLink 10.6.5 (EN/NL/FR) - Previous version
Previous version of VelbusLink
XLSX-File Velbus consumption calculator
Spreadsheet to calculate the number of power supplies you need in a Velbus installation.

Info Sheets

PDF-File Infosheet
HTML-File Velbus actions by module (click on an action to see a description)
List of actions per module
Q. The lights connected to my VMBDMI(-R) are not completely turned off
A. I have a light circuit connected to a VMBDMI(-R). When the lights are dimmed out, they keep on emitting a bit of light.
To solve this problem, put a relay (eg. of a VMB4RYNO module) between the dimmer and the lamp. Then create an action "Momentary (follow)" with the dimmer as initiator, and the relay as subject.
This relay will always be closed, except when the dimmer is set to 0%.
Q. Light switched at 100% during the day and 25% at night
A. A light needs to be switched at full intensity during the day (07:00 - 23:00), but at night (23:00 - 07:00) at a dimvalue of 25%. How to program this in Velbuslink? Read more ... (PDF)
Q. Dimming with Velbus
A. An overview of the most common options for dimming with Velbus. Read more ... (PDF)
Q. Setting the minimal dimvalue
A. If the connected lamp does not function correctly at lower dimming values, set a minimal dimvalue in the dimmer's configuration settings. In order to set it correctly, proceed as follows:
- right-click on the dimmer channel and select "operate"
- set the current dimvalue to 1%. Leave this value at 1% for the rest of the proces.
- close the "operate" dialog, select the dimmer and open the configuration settings of the dimmer
- in the configuration settings, enter a minimal dimvalue of 1% and synchronize > write this new setting. If the lamp functions as desired, leave the setting as is.
- If the lamp does not function as desired, increase the minimal dimvalue (in the configuration settings) by one or more percent at a time, synchronize > write the new value and check whether the lamp works correctly.
- repeat the previous setting until the ideal minimal dimming value has been found.

It might be advisable to let the lamp heat for a while by putting it fully on, then check again if the minimal dimvalue is correct.
Q. How can I make a motion detector set a light to a certain dim value during a certain time?
A. A Velbus motion sensor needs to turn a light on at a certain dim value (eg. 50%) during a certain time (eg. 1 minute).
This can be done as follows:
- in the configuration of the Velbus motion sensor module, set the timeout of the motion output to 1s
- create an action "Set to percentage" with the motion output channel as initiator and the dimmer channel as subject. Set the dim percentage parameter (in our example 50%). This action has also a "duration" parameter. Set this to the desired on time (in our example 1 minute)
Q. My led lights are not dimming correctly
A. If the connected led lights are in accordance with the specifications of our dimmer but do not dim correctly (eg. buzzing, flickering, turning off by themselves, ...) an electronic pre-charge may possibly be a solution. The electronic pre-charge is specifically useful in case of induction, or if the load is not high enough.
Q. Making the same button switch a light on/off at 70% luminance during the day and at 40% during the night?
A. In the night hall I have a light that I need to switch on/off at 70% luminance during the day, and at 40% during the night. Read more ... (PDF)
Q. Atmospheric dimvalue toggle in one button
A. How can I toggle an atmospheric dimvalue (eg. set dimvalue to 25% / off) with one button? Read more ... (PDF)