The dim function modifies the status of a dimmable output between 0% (off) and 100% (on).
The DIM function, sometimes referred to as the ‘dimmer’ function, can be considered one of the most basic PROSOFT functions. But if you are a novice with PROSOFT, you may need more information, because the DIM function has more to offer than just dimming a light.

What is the DIM function?

First of all, a PROSOFT ‘function’ defines the relation between a system input and a corresponding output. Typically, an 'input' encompasses various options, such as standard push buttons, technical contacts and the buttons found on TELETASK touch panels (for example an AURUS touch panel). Input contacts may be from a motion sensor, a door or window contact, and alarm output contact and many more.
The DIM function is typically utilized for controlling the status of a dimmed light or circuit of lights. When the button is pressed, the dimmed output is brought to the desired dim level.
Let's look into the DIM function itself. In this case, an input (touch panel button) is linked via the ‘dim’ function to - most often - a power dimmer channel. But this function can also be used to connect an input to an analogue output (e.g. 0-10V or 1-10V) or a DALI dimmer control output (e.g. via the TDS13621 DALI interface).

Figure: An input triggers the ‘dim’ function in the central unit and this influences the dimmer output (between 0 and 100%).

The DIM function boasts several key features:

• Ubiquitous Usage: The DIM function stands out as one of the most frequently used PROSOFT functions.
• Versatile Control: its role is to manage the dim level of a lamp or a light circuit with multiple lamps.

The DIM function in action

In most applications, a standard button or a touch panel button is related to a power dimmer output. In default situations, when clicking a dimmer button, the light will be dimmed up to 100% (full on). When clicking again, the light will be dimmed to 0% again (off). As a matter of fact, by default in a TELETASK system, the light will go back the the former dim level.
If the light was at 50% level before your turned it off, and you click the control button again, the light will be dimmed back to the memorised 50% level.
When you change the dim level by clicking long on that dimmer button, a new dimlevel is reached when you release the button and at the same time this level is stored as ‘the last dimmed level’ in the system memory. Even if the power fails, the TELETASK system keeps the status in its non-volatile memory. After power-up, the system will bring all dimmed lights back to their last status (as like it was at the moment of the power failure). So when you sleep in the night and all lights are off, at power recovery, all lights will remain off. Nobody will be disturbed in the night. But if the power fails when you are dining and some dimmed lights are partly or fully on, after power comes back, all individual levels will be set again to all dimmers. Even if you have 1, 5, 10, 100 or 5000 of those.

Some fundamental applications of the DIM function include:

• Lighting control: controlling lights to generate light levels for a technical reason or for mood generation by a single light or to obtain specific scenes with multiple light circuits. In this case, you can use a LOCAL MOOD function with preset DIM levels (and/or other functions) in it.
• Wall Socket Control: managing the dim level of a dimmable light device (e.g. a dimmable up-lighter) plugged into a dimmer connected wall socket. A power dimmer output may be connected to multiple dimmed wall sockets as well. Please keep all limits, the local regulations and the maximum allowed power of the power dimmer in mind. It is absolutely (!) recommended to use a special type of wall socket to avoid non-dimmable or high-power devices being plugged into that dimmed wall socket (e.g. vacuum cleaner, audio/video equipment, or non-dimmable light equipment). This may damage the power dimmer and/or the device.
• Fan Control: NEVER use a standard power dimmer output (e.g. TDS13642, TDS13644) to control a fan (speed). Both the fan and the power dimmer output may be damaged. An AC fan, ‘dimmed’ by a power dimmer, can heat up and generate a risk of fire.
• On the other hand, an AC or DC fan system can be controlled by an analogue output (e.g. 0 to 10V signal) if the fan device is suited for that specific control signal.
• Floor heating/cooling motorised valves: you can use an analogue output of the TELETASK system to control a servo motor-driven two-way or three-way water or air valve. See the heating/cooling set-up for more information on working with 0-10V servo motor driven heating/cooling valves.

But dimming is more than just dimming...

Example 1: safety measures

The DIM function, just like the RELAY function, serves not only as a practical means of dimmed or on/off control but also frequently integrates safety features. As a result, the DIM function may not always be directly associated with a push button, but rather incorporated within a predefined mood. Consider for instance a scenario where the light on a staircase needs to be on when somebody approaches and uses the stairs in low-light or dark situations. Those kind of lights may be obliged to be ON as soon as the (outdoor) light level gets low. A manual control with a button or motion sensor may not be good enough for such an application. A time-based control in combination with light sensing may be needed. To avoid a light sensor, you can use the built-in astrological clock function instead.
But there is also the possibility that the TELETASK system can step-by-step increase the dim level according to the sensed lowering indoor/outdoor light level. You may put a goal of for example 600 lux. If that level is not reached, the TDS system will increase the concerned dimmer output to obtain the necessary 600 lux. Safety and energy management in one functionality.

Example 2: energy savings

When a light or a circuit with multiple lights is dimmed, it will consume less energy than when at 100% (on). When using lights that are activated for many hours a day, in the long run, a dimmer application may be more energy-friendly than a simple on/off control. So when light is needed, try in your configuration to dim the light as much as possible and as allowed for safety reasons. The lifetime of the light may also be extended and it generates a double- win situation.
Remark: in places where safety is an issue, keep a minimum level in mind, and check the local safety standards and regulations.

Example 3: TIMESOFT clock action

A DIM function can also be used in a TIMESOFT clock action. E.g. when you might activate the entry or staircase lights during certain periods of the day and if the indoor light intensity drops (e.g. below 15 Lux), and the clock time is between 5 and 11 pm and only when it is Monday to friday? This requires a combination of a light sensor flag and a clock-based flag, which are checked within a Conditional function called by a PROCESS function... Don’t worry if you don’t understand this yet because this is a skilled function for experienced system integrators. Your TELETASK support team will be glad to help you in such a case. It is just a matter of describing what you exactly want to obtain.
Conclusion: like most of the TELETASK functions, the DIM function can be a component of more intricate logic conditions.

Example 4: Mood generation

Lastly, you can leverage the DIM function within a Local Mood when you need to set multiple dimmers to specific statuses by simply clicking a button or closing an input contact. For instance, this is handy when leaving a certain room (for an all-off action), in which you have various devices to manage. Typically, these devices include lights, uplighters, etc.. but also other functions like HVAC, shades, curtains, and audio functions may be altered in such LOCAL MOOD.
It's worth noting that in the more powerful ‘General Mood’ function, dimming, on/off and other controls can be directly executed without the need for individual dim functions.

Unique features of the DIM function (PROSOFT settings)

Below, we explain the DIM function configuration in PROSOFT.
In PROSOFT you can do all the necessary settings to use the DIM function. Just click the panel or input which you want to configure and select your preferred settings for the button and dimmable light circuit you want to control. Don’t forget that first of all, you will also need configured dimmer output interfaces. So define the dimmer outputs before you start with the input (buttons) configuration.
In the example in the screen capture below, you can see the default setting when you select the DIM (dimmer) function. PROSOFT will automatically assign the "LAST level/OFF" control for a ‘short’ press on the button and the ‘Continuous dimming’ as the ‘long’ press function.

But, by selecting other than default options in the ‘Short’ and ‘Long’ press action fields, a DIM function can be used in several other ways as well. See a detailed overview of the options here below.

1. behaviour of the DIM function (’Short’ and ‘Long’ press options)

As already mentioned above in this chapter, in some applications, a standard button or a touch panel button is related to a power dimmer output. When clicking the button, the light will be dimmed to full on (100%). When clicking again, the light will be dimmed back to off (0%). As a matter of fact, by default, the light will go back the the former dim level. If the light was at 50% level and you click the button, the light will alter between 0% and 50%.

The “Fade- in” and “Fade-out” dimming speed parameters

For each dimmer control (button) you can define an individual dimming speed, which is called the ‘ramp speed’.
The “Fade in” parameter defines the needed time to bring the dimmer output from 0% to 100%. The 'Fade in' can be set to 16 fixed predefined times: 0,5 sec;1 sec; 2 sec; 3 sec; 4 sec; 7 sec; 10 sec; 15 sec; 30 sec; 1 min;2 min; 5 min; 15 min; 30 min; 1 hour.
The standard 'Fade in' is set by default to 1 second. By increasing this parameter, you can give the user a more sophisticated experience. The same for the ‘Fade out’ parameter. Fade-in time is most often limited to 1 to 3 seconds to avoid that you have to wait to enter a (priorly dark) room. The fade-out can be longer because there you don’t have the waiting aspect.
The ”Fade out” parameter defines the needed time to bring the dimmer output form 100% to 0%. The 'Fade out' can be set on 16 fixed predefined times (identical to 'Fade in'. Standard 'Fade out' is set on 3 sec.

At an increase towards the desired status the dim speed is calculated in accordance with the set 'Fade in: when the difference between the desired and the active status of the dimmer is 20%, the dim speed time is also 20% of the 'Fade- in' time. The result is that the dimming (from this button or input) will always work at the same preset speed.
This is the same for the ‘Fade-out” setting and its dim speed.

’Long’ press fixed dim speed
The above fade-in and fade-out settings are used in all standard cases when you click briefly (short) on a button. Then the set times are used. But when the user clicks Long on a button (in most of the cases) to manually dim to another specific level), a relatively fast - fixed - ramp speed is used by the central unit.

Other button option settings

There are five optional settings for a dimmer control:

By default the ‘LAST level/ OFF” option is set.

1. The “SET level/OFF” (toggle) setting

If your customer wants the light circuit always to go to a specific level (e.g. 60%) and to 0% when he/she clicks the button again, you need to select the “SET level/OFF” option. In this case, you also have to enter the desired target value (e.g. 60%).

2. The “SET level” setting

With this option, there is no toggle function anymore available on the button. Any time you click the button, the system will set the dimmer output to the preset SET level (a value between 0 and 100%). This means, that if the level was already at the set level, nothing will happen (no toggling of the output to 0%).
This option is often used on the buttons of an AURUS-OLEd touch panel when a dimming control is on two buttons beside of each other. The left one may be used to dim UP and the right one to dim DOWN or vice versa. See details on how to configure this below under the ‘Long’ press options.

3. The “SET Last level” setting

In this case, the button will set the dimmer level back to the last (former) used dim level.

4. The “SET Last level/100%” setting

In this case, the button will also bring the dimmer level to the last (former) used dim level but it is also a toggle function and the output will toggle between that last level and 100% (full ON). There are few applications for this functionality, but you never know...

5. The ‘Long’ press options

If the user clicks ‘long’ on a button with DIM function, the light circuit will be dimmed up or down, depending on the last dimmer direction. Every time the button is clicked ‘Long’ the direction changes to the opposite. Also when the dimmer level is 0% or 100% is reached, the dimming direction will change when clicking the next time Long again.

If you have an AURUS-OLED and you want to have two buttons to control a dimmed circuit, you can use the Long function very well. Two buttons are coupled in a horizontal line. The left button will need to get the ‘Dimming up’ option in the Long press field, while the right button gets the ‘Diming down’ option (or vice versa).
PROSOFT will automatically make the proper display zone for you in the middle of the AUUS-OLED screen, including up and down arrows.

''Example: In a guestroom, the top two buttons could be combined to dim the ceiling lights.
The left button to dim DOWN / The right button to dim UP''

When buttons are ‘coupled horizontal’ on the AURUS-OLED, the selected icon is placed in the middle and the up/down arrows beside of it (automatic)

'Dimming Down' type:

When pushing long on a button, the dimmer will decrease from the active status to 0%.

'Dimming Up' type:

When pushing long on a button, the dimmer will increase from the active status until it reaches 0% or 100%.
In the example picture from above, this looks in PROSOFT like in the capture below:
1. The ‘couple horizontal’ arrow in the lower right corner indicates that both buttons control the same dimmer output
2. The ‘Long’ press option is ‘Dim down’ for the left button and ‘Dim Up’ for the right button.

Other general Info:

- the behaviour of the dim function is the same for dimming from a contact input (with a standard bell push button) or dimming on a touch panel button (on an AURUS touch panel).

- OPUS:
Dimming a light on an OPUS touch screen is done by selecting the room and then the desired light icon. A slider appears to set the desired dim level.
If you click on the indicated dim level percentage, this toggles the dimmed light between that last dimmed level % and zero % (off).

- ATMOS:
Dimming on the ATMOS mobile app: If you have the dimlevel on the ATMOS screen, you can click on the left side to toggle and on the right side to get a slider.
- An application example of a long fade-out time (for example 30 minutes)
In a baby’s bedroom, the parant can use a fade-in of for example 10 seconds to avoid the baby being scared when entering in the dark. On the other hand, a long fade-out may be interesting to help a young child or baby to go sleeping. When leaving the room, after putting the baby/child to bed; the parant can long click a button with ‘Set Level’ with a fade-out of 30’. The baby is happy to stay in an illuminated room and the light will only be faded out after a long time (30 minutes), when the baby/child is already sleeping

- MINIMUM DIMLEVEL
In PROSOFT, in the definition of a dimmer output (e.g. on the Power FET dimmers TDS13642/TDS13644), you can set the minimum dim level (see screen capture below - lower right corner). This is used when your LED lamp doesn’t start giving visual light at 1% but for example only when the dimlevel is minimum 15%. The specific “mimimum DIM level” is to be found on the packing or data sheet of your lamp/unit.
When you enter such a level, the TELETASK central unit will jump without considering the fade-in time (when dimming up from 0%) from 0% to this level, so the dimming also starts immediately.

The Minimum DIM level and Curve type can be set in the output interface screen in PROSOFT (see the lower-right corner of the screen capture above)

- DIM Curve
In PROSOFT, in the definition of a dimmer output (e.g. on the power FET dimmers TDS13642/TDS13644), you can also set the dimmer curve to be used by the interface. Depending on the selected type of lamp, PROSOFT auto-selects the proper curve for you, but if you want it to be different, you can always change it. A lamp that works more linear is best controlled with a linear curve but maybe you need a more progressive curve to obtain the best linear dimming behaviour for the best user experience.

- lamp type and LEADING / TRAILING edge selection
In the power dimmer interface screen in PROSOFT, you can select the proper “Lamp type”. By default, it is set to ‘dimmable LED’, which is suitable in most of the cases. Together with the Lamp type, PROSOFT also selects the necessary way (leading or trailing edge) of dimming (for TDS13642 and TDS13644 power dimmers). So you don’t need to take care about this if the Lamp type is properly set. We recommend using LED lights only.
Remark: If you use an analogue output or DALI interface for dimming your devices, these settings are done by the specific power dimmer and are not to be set in PROSOFT. A setting in the third-party power dimmer may be necessary.

- COLOUR lights
Dimming of any colour is no different for the use of all the above settings. The only thing you may need to do is use an RGB function in PROSOFT to define the 3 different outputs (R, G and B colour control output) as one RGB unit. In PROSOFT you will then only use the RGB function for dimming (and colour setting) instead of doing a direct approach to the individual RGB outputs.
On the TELETASK touch screens and ATMOS app, you can define a colour wheel to control the RGB device more graphically.
On individual buttons or buttons of the AURUS touch panels, you can define colour presets to obtain specific colours and light levels.

- TIMED dimmer actions
If you need to control (dim) a light circuit, based on a clock (time of the day) or a time (for several minutes), you can use the DIM function in TIMESOFT or use the Timed function or a TIMED LOCAL MOOD for such purposes. See more details in the description of these functions in the Technical (online) Handbook in the ‘Professional’ part of the TELETASK website www.teletask/be/professional.

Conclusion

In summary, while the DIM function is commonly used to control a dimmable light circuit, from a button or touch panel, there are several more settings possible to obtain your customer’s goal. Don’t forget that one of the most important goals is to make the use of the living environment simple and easy for everyone. Don’t forget that a lot of users are non-technical and not interested in automation at all. They just want to obtain what is needed: an increase of user comfort, optimised energy management and the highest possible safety for everyone living and working in the concerned house or building. The DIM function can certainly help you.

If you need more details about PROSOFT functions, you can search for them in the Technical Support system on this website.

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