Backlighting the pressure gauge of a professional coffee machine can improve readability, design and product recognizability without altering the delicate measuring mechanisms.
SLIM has developed an LED solution that can be applied to the rear of the pressure gauge and is designed to transmit light to the dial through simple small holes. The result is a thin, customizable lighting component that can be easily integrated into the production process. This is a concrete example of how custom indicator lights can turn a standard technical element into a distinctive detail, while keeping lighting, precision mechanics and the original functions of the device separate.
Backlighting can enhance the pressure gauge
without changing how it works.
Do you have limited space, or are you concerned about having to redesign a pressure gauge?
We can assess a lighting solution compatible with your project.
- Why backlight the pressure gauge of a professional coffee machine
- The problem: providing light without interfering with the pressure gauge mechanism
- The SLIM solution: an LED module applied behind the pressure gauge
- Why place the LED module on the rear
- How light passes through the holes
- How the backlit dial works
- Which elements of the pressure gauge can be illuminated
- Backlighting with white LEDs or colored LEDs
- Can light also indicate pressure status?
- Which voltage should be used for the backlighting module
- Possible configurations for backlighting
- How much space does pressure gauge backlighting require?
- Integrated backlighting or external module: which solution should be chosen?
- What advantages does it offer pressure gauge manufacturers?
- Advantages for Coffee Machine Manufacturers
- Why entrust the backlighting project to SLIM
- Frequently asked questions
- Additional suggestions
- Further reading from the SLIM blog
- Glossary
- Turn the pressure gauge into a distinctive element of the machine
The pressure gauge is one of the most recognizable elements on the front panel of a professional coffee machine. It displays circuit pressure and contributes to the technical image of the machine.
When the dial is not clearly visible, is set into a dark panel or is located in an environment with variable lighting, reading it can become less immediate. Even when readability is already adequate, the pressure gauge can appear visually disconnected from the rest of the interface.
Backlighting makes it possible to address both aspects:
For an industrial designer, the difficulty does not simply lie in adding a few LEDs. The real challenge is to illuminate the dial uniformly without interfering with the mechanical components inside the pressure gauge.
Value does not come from the amount of light,
but from how the light is integrated.
Springs, levers, brackets and other precision mechanisms may be present inside a pressure gauge. Introducing a lighting circuit into the body of the device can create issues relating to space, assembly, maintenance and reliability.
Backlighting designed without considering the internal structure can:
The solution must therefore meet a precise requirement: the light must enter the pressure gauge, while the lighting module must remain outside the mechanical area.
This is the principle adopted in the project developed by SLIM for a manufacturer of pressure gauges intended mainly for professional coffee machines.
The light must reach the dial, not invade the mechanism.
SLIM designed a thin plastic body that fits onto the metal back of the pressure gauge. The backlighting module therefore remains on the rear of the device and does not come into contact with gears or precision springs.
The light produced by the LEDs is transferred inside through suitable holes prepared in the back of the pressure gauge. This configuration keeps three functions separate:
The module does not have to be placed inside the cylinder containing the mechanism. The manufacturer only needs to provide light passages and an electrical power point.
The result is a solution similar to a plug-in option: the same pressure gauge model can be supplied in the traditional version or completed with backlighting.
A minimal pre-arrangement can create
two commercial versions of the same pressure gauge.
Rear positioning of the LED module solves several design problems at the same time.
This approach can reduce the need to manage two completely different mechanical designs.
Separating the lighting module means simplifying
production, customization and maintenance.
The LEDs are positioned in line with the holes made in the back of the pressure gauge. Each opening allows the light to reach the transparent or semi-transparent dial. The number, diameter and position of the holes must be assessed according to:
The holes required to diffuse the light depend on the configuration selected for each specific project and are not a universal rule. In another application, one or two LEDs might be sufficient, or a larger number of light points might be required.
The right LED module comes from the actual geometry of the pressure gauge, not from a generic solution.
The dial can be made of a transparent plastic material, such as Plexiglas, onto which numbers, scales, symbols, backgrounds and brand marks are printed. Printing does not only serve a graphic purpose. It also controls the passage of light.
The areas that must remain dark are covered with sufficiently opaque printing. The parts that must light up are left transparent or semi-transparent, or are treated with colors capable of diffusing the light.
In the project described, the dial has a black background. The white areas can instead be illuminated, including the scale, numerical markings, logo and outer frame. This system makes it possible to obtain different effects without modifying the LED circuit:
The dial graphics become
an integral part of the lighting design.
Backlighting can involve the entire dial or only selected information. The choice depends on the function of the pressure gauge and the desired effect. Selective lighting can highlight the main scale, while more diffuse light can enhance the entire surface.
Elements that can be illuminated include:
Important: excessively bright areas, irregular shadows or LED points directly visible to the operator must be avoided. The dial must appear uniform even when viewed from the front or from a slightly lateral position.
Good backlighting shows the information,
not the point from which the light comes.
The first prototype was developed with white LEDs, a choice suited to a black dial with light-colored graphic elements. White light provides a clean result that can be easily integrated into machines with different styles. However, many other options are possible. SLIM can assess LEDs that are:
The color must be selected by considering the dial material, the inks used, the visual identity of the machine and the other light sources present on the panel. A cool light can emphasize a technical, contemporary design. A warmer light can harmonise with metals, wood, bronze finishes or refined HORECA environments.
When connected to machine control,
light can become information.
The project developed uses a 12 V power supply, but voltage is not a fixed limit of the solution. The circuit can be sized for different values, such as 16.5 V, 24 V or other voltages requested by the manufacturer. The choice depends on:
Professional coffee machines normally have an electrical system from which a suitable power supply can be derived. The branch connection must nevertheless be assessed by the machine designer and sized according to the applicable electrical specifications.
The table summarizes the main design requirements linked to the backlighting of a pressure gauge. For each requirement, it presents the possible technical solution and the concrete advantage for manufacturers and designers. It highlights how module position, number of LEDs, voltage, footprint and graphic customization can be adapted to the characteristics of the coffee machine.
|
Design requirement |
Possible solution |
Main advantage |
| Keep the mechanism intact | Module mounted on the rear | No interference with springs and gears |
| Illuminate a compact dial | Multiple distributed LEDs | Greater lighting uniformity |
| Produce standard and illuminated versions | Pressure gauge prepared with holes | Range flexibility |
| Adapt to the machine circuit | Custom voltage | Simpler electrical integration |
| Enhance the brand | Translucent logo on the dial | Greater recognizability |
| Communicate operating states | Multicolor or RGB LEDs | Immediate visual signalling |
| Reduce the footprint | Thin rear circuit | Installation in limited spaces |
Voltage, number of LEDs and geometry
must be defined as a single system.
One of the most frequent problems in coffee machine design is the lack of space behind the front panel. Pipes, wiring, valves, structures, electronic boards and fastening systems compete for a few centimeters of available space. This is why the module must have a reduced thickness and a geometry compatible with the back of the pressure gauge.
In the case developed by SLIM, the device was designed as a very thin element with a limited rear footprint. Connections and soldering points must also be protected and positioned so that they do not create interference.
Before defining the solution, it is advisable to check:
In a reduced space,
every millimeter must have a precise function.
An integrated source inside the pressure gauge may seem the most direct route, but it requires space and a deeper review of the device. The rear module instead offers greater separation between the lighting part and the mechanism.
This can be suitable when the pressure gauge is designed from scratch and has sufficient space. It allows direct control of light distribution, but can make assembly, calibration and maintenance more complex.
This is particularly suitable when the aim is to evolve an existing pressure gauge. It requires preparation of the optical passages and power supply, but leaves the area housing the mechanisms unchanged.
A source directed from the outside towards the dial is simpler in some applications, but it can produce reflections on the glass, shadows and glare. In addition, the aesthetic result is generally less integrated.
For the case described, the rear solution represents the best balance between footprint, mechanical independence, visual quality and production adaptability.
The best solution is the one that illuminates the dial
with the least impact on the product.
For pressure gauge manufacturers, backlighting can become a new range option. A traditional component can be offered in a version intended for coffee machines with greater focus on design, readability and customization. The main advantages are:
The pre-arrangement can be introduced into the production cycle with limited processing, provided the hole positions, tolerances and fastening systems are defined in advance.
An illuminated pressure gauge is not only a component:
it can become a range option.
For the machine manufacturer, a backlit pressure gauge makes it possible to update the panel without replacing the measurement technology. This aspect is important when the analogue pressure gauge is part of the machine's identity. Many professional products combine digital displays, electronic controls and traditional mechanical elements.
Backlighting makes it possible to maintain this balance while adding:
The machine remains technically the same, but its visual language can change significantly.
Even an existing component can contribute
to the aesthetic repositioning of the machine.
A module for a pressure gauge cannot be selected solely on the basis of diameter or voltage. Mechanics, optics, graphics, power supply, available space and assembly process must all be assessed at the same time.
SLIM has been developing luminous signaling components for decades for household appliances, professional equipment, coffee machines, HVAC, automation and other industrial sectors. Its experience in LED technology makes it possible to address projects in which a standard component must be adapted to a specific space, interface or product identity. The discussion can start from:
The project can then proceed through feasibility assessment, prototyping, testing and industrialization.
The most reliable backlighting is created when supplier, designer and manufacturer work on the same problem.
It depends on the structure of the device. Orman pressure gauges are fully capable of being equipped with backlighting. Rear space, the possibility to prepare light passages and access to an electrical power supply are required. A check of the sample or technical drawing makes it possible to establish feasibility.
Yes, if graphics, contrast and materials are also designed for passive reading. Numbers and scales must not depend exclusively on the module being switched on.
Yes. The dial printing can obscure the areas not involved and leave only the logo translucent, creating selective backlighting.
Yes, if the circuit and the machine control system include current regulation or a compatible electronic command. This requirement must be defined during the design stage.
A separate rear structure can facilitate replacement, but the actual possibility depends on fastening, wiring and accessibility inside the machine.
Yes. Color, intensity and light temperature can be studied together with the other indicators on the panel to obtain a visually consistent interface.
1. Design a night mode or reduced-brightness mode:
In venues with soft lighting, a dial that is too bright can become a dominant visual point. Providing two brightness levels allows the machine to adapt to different environments.
2. Use the prototype to verify the print color:
The same LED can appear different through different inks, materials and thicknesses. It is therefore useful to test the final dial, not just a generic transparent sheet.
3. Consider the illuminated pressure gauge as a commercial configuration element:
Backlighting can distinguish a premium line, a special version or a customized version for an OEM customer, without changing the basic function of the machine.
PWM
An electronic technique that regulates the power supplied to a source through very rapid pulses and can be used to control its brightness.
Light guide plate
A plate designed to distribute, over a surface, the light produced by sources located at the edges or in specific points.
Binning
The process by which LEDs are selected and grouped according to characteristics such as color, brightness and voltage.
Potting
Encapsulation of a circuit in a protective resin to increase insulation and resistance to moisture, vibration or contaminants.
Derating
A conservative reduction of a component's maximum operating values to increase reliability and service life under the expected operating conditions.
Pressure gauge backlighting can be integrated without invading the mechanical part and without altering the measurement function. A thin LED module, designed around the actual geometry of the device, makes it possible to illuminate scales, numbers, logo and frame, adapting voltage, color and number of sources to the manufacturer's requirements.
SLIM can support pressure gauge manufacturers, designers and coffee machine manufacturers in technical assessment, prototyping and development of the solution intended for production.
Overcome space constraints and turn a standard component into a recognizable detail.