Mean Well LED driver offers dimming function to fit the modern lighting control demand. LED driver

will change its output current based on 3 different input signal/setup including DC 0(1)-10V, PWM

and 100K ohm resistor dimming. The difference between DC 0-10V and DC 1-10V has been addressed

in the previous article*. This application note describes how a commercially available dimmer to

work with Mean Well LED driver. 

Potentiometer: simple solution with problems

One of the solutions to dim with the LED driver is just to use a simple adjustable 100k ohm

potentiometer shown in the Figure 1. This is a cost effective solution and works well with the LED

driver. However there are two essential drawbacks which makes it in some cases less suitable. First

the dimming response is not good in case there are multiple LED drivers connected to one

potentiometer. Second there is not much choice on the frame plate in terms of color, material to be

used in the house where fullness and harmonized interior design is desired. Because of these

drawbacks, electronic potentiometers were invented to resolve the issues described before.

Mean Well 0-10V dimming

There are many electronic potentiometers available on the market from the manufacturers of

electrical installation and building system. Sometimes it is also called DC 1-10V dimmer because the

potentiometer converts the current from dimming port of LED driver into DC 1-10V. These can be

found online using the keyword “Potentiometer 1-10 V” in Google. Most of these have same or

similar electronic design. Electronic potentiometers provide two main functions: Switch On/Off and

potentiometer as illustrated in Figure 2. The switch function allows the user to change the light

output state by pressing the dimmer which has an equivalent circuit in Figure 2(c). Further the

electronic potentiometer provides a dimming function. In general the sink current of dimmer

determines the max. allowable number of LED drivers connected to it. For instance, dimmer shows 50mA on the label which indicates it can theoretically connect up to 500 LED drivers in parallel due to

the fact that each Mean Well LED driver generates 0,1mA output current. However the final

allowable device should also consider based on the type of fuse inside dimmer which is subject to the

Inrush current of AC current of LED driver. For instance, 0,5A ceramic fuse is used inside the Figure

2(c). The calculated number is 5 in case the rated input current on each driver is 0,1A. As result the

max. allowable number of driver connected to dimmer in this example is just 5 by comparing the

calculated results from dimmer current and fuse.

Connecting an electronic potentiometer to LED driver

The installation manual of electronic potentiometer or DC 1-10V indicates the conventional way to

connect it to driver shown in Figure 3(a). It is suitable both Mean Well driver with DC 1-10V and DC 0-

10V. The switch of dimmer is connected to AC mains so that the LED driver is surely switched off

when needed. However such connection has risk of electrical shock during wiring due to the present

of high voltage. Another possible connection is proposed in Figure 3(b). Such connection does not

need to work with high voltage because there is no need to connect the AC mains wire on dimmer

side. The dim to off function provided by the Mean Well DC 0-10V LED driver is used to put the driver

into standby mode in case the button of dimmer or electronic potentiometer is pushed. As result, it

is very important that the standby power consumption is low to save the energy. All Mean Well LED

drivers with DC 0-10V dim to off function are designed to have low standby power while compliant

the latest Ecodesign or ErP regulation required by CE. LED driver with DC 1-10V may not suitable for

Figure 3(b) connection simply because it is not equipped with dim to off function.


This articles explains commercially electronic potentiometer/DC 1-10V dimmer can work well with

dimmable Mean Well LED driver. There are two connection provided for user to choose which suits

the best. A quick overview is given in the Table 1. The new proposed connection in Figure 3(b) is

suggested because it avoids the electric shock when electrician is working with DC 1-10V electronic

potentiometer. Additional benefit is the reduction of excess cost due to miswiring or incautious

action. The max. number of LED drivers connected to dimmer compared with conventional

connection is higher because it does not need to take the fuse of dimmer and AC current of driver

into account. Also the false trigger of circuit breaker due to high inrush of driver would not be an

issue because the driver is not turned on/off at primary side. Table 2 gives the list of dimmers on the

market which proof the concept.