Application example: Safe opening and closing of automatic doors and windows
Modern building technology can no longer be imagined without automatically operated doors, gates, and windows. To prevent damage and injury, industrial, commercial, and residential buildings frequently utilize switching strips and contact strips used for the safe opening and closing of automatic doors and windows. They are typically employed to detect obstacles and prevent doors or windows from closing on people, objects, or limbs.
Depending on the installation situation and specific usage, there is a potential danger to people and objects during closure. Mayser offers pressure-sensitive sensors that respond quickly and provide reliable protection in hazardous areas, regardless of interfering factors like lighting, dirty surfaces, or weather conditions. The goal is to offer maximum protection in a user-friendly design.
Depending on specific application areas, various solutions are available:
- Sensor profiles and switching lists
- Safety edges, contact strips, and miniature switching lists
Electrically operated doors and windows are considered machines according to the Machinery Directive and must comply with specific safety requirements. Mayser's pressure-sensitive sensors are tested according to EN 12978 and/or EN ISO 13849 and/or EN ISO 13856 standards, thus meeting the safety-related requirements of the Machinery Directive.
Construction of a switching strip
A switching strip consists of an aluminum mounting rail and a rubber profile with two safety contacts integrated opposite each other in the rubber profile. When something presses against the switching strip, both safety contacts make contact with each other, causing, for example, a roller door to stop. There are two options for connecting a switching strip. The simplest is the 2-wire option, where the contact strips at one end of the switching strip are connected to the controller (one circuit). At the other end, an end cap/plug with a resistor is then placed. The other option is to connect the switching contacts to the controller at both ends (two circuits). The advantage of this is that there is a continuous double system check, making this option also fall into a higher safety class (PL e instead of PL d). For the 2-wire option (one circuit), the SG-EFS 104/2 W controller from Mayser is suitable, for example. For the 4-wire option (two circuits), the SG-EFS 104/4 L controller from Mayser is suitable.
Operation of the switching strip
The control unit monitors the circuit. When sufficient force, measured in PSI or Newton, causes the two integrated safety contacts to make contact with each other, the controller detects the resulting change in resistance and generates a signal in the form of "on" or "off." This signal is then relayed to the control unit of the secured machine or to a safety circuit specifically designed to stop or open the enclosure or gate on which the safety strip is mounted.
Broken or short-circuited wire
It is important to note that a fault condition, such as a broken or short-circuited wire between the controller and the safety strip, results in a fault condition, also known as an interlock. The safety contact strip controller complies with the requirements of category 3, as specified in the EN 954-1 standard.
Switch strips on automatic windows
Imagine a building with large glass windows that can be automatically opened and closed. To ensure the safe operation of these automatic windows and the protection of users, (miniature) switch strips and contact strips are used as safety sensors. The (miniature) switch strip is attached to the edge of the door or window. When a person or object touches the switch strip, pressure is applied to the sensors, and a signal is sent to the control system. This signal informs the system that an obstacle has been detected, causing the door or window to stop closing and possibly return to the open position. In this way, potential injuries to individuals are prevented.
Angles and Installation Space
There are situations where attaching a standard switch strip is not possible or angles of 90 degrees pose problems. Standard switch strips come with an aluminium profile. It is possible to install these traditional switch strips at 90 degrees, but often the installation height is insufficient for standard switch strips. In these situations, the EKS series miniature switch strips from Mayser provide the solution.
Miniature switch strips and contact strips
Unlike traditional switch strips, miniature switch strips and flexible contact strips are designed to bend easily and adapt to different angles and shapes. This makes them particularly suitable for situations where switch strips need to be placed at a sharp 90-degree angle.
Flexibility of Miniature Switch Strips
Thanks to their flexibility, miniature switch strips and flexible strips can be bent to perfectly fit the contours of the frame, even if they are complex or sloped. This simplifies the installation and ensures the safety of automatic windows, even in challenging architectural environments. Additionally, miniature switch strips have the ability to move along with the object they protect. Learn more about miniature switch strips and contact strips.
Switch strips on automatic doors
Switch Strips (with Safety Function) are often applied to automatic doors and sliding gates. They play an important role in detecting obstacles and ensuring the safe operation of the doors. Here are some aspects related to the use of switch strips on automatic doors:
- Obstacle Detection: Switch strips are typically located at the edges of the door, both at the top, sides, and bottom. When a person, object, or even a body part, such as a hand, touches the switch strip, pressure is exerted on the sensors in the strip. This triggers a signal to the door's control system.
- Stopping or Reversing: Once the control system receives the signal that pressure is applied to the switch strip, the door's movement is halted or reversed. This prevents the door from closing unintentionally and posing potential injury risks.
- Safety Features: Switch strips are often used in conjunction with other safety features, such as motion sensors and safety systems. These components work together to ensure that the door operates safely and reliably. For example, if the motion sensor detects a person approaching the door, the system will open the door, and the switch strips ensure that the door doesn't close as long as pressure is applied.
- Flexibility and Adaptability: Switch strips are available in various sizes and can be tailored to the specific dimensions of the door. They are designed to be flexible and are suitable for various door configurations, including single doors, double doors, sliding doors, and revolving doors.
Profile and strip properties
The sensor profiles are resistant to extreme loads, custom-made, feature an anti-slip and robust design, and must meet stringent quality controls. All profiles undergo comprehensive environmental and durability testing and have a B10D value of at least 2 million test cycles.
IP68 Protection Class
Even DIY sensor profiles provide protection against dust and water according to IP67 protection class. Upon request, we also offer a DIY version with IP68 protection class.
Miniature safety edges are specially designed for limited travel distances and minimal installation heights. They are particularly suitable for use in window and facade technology to protect fingers from pinching. Miniature safety edges can be easily adapted to different bend radii and angles.
Switch strips on automatic doors in a shopping centre
Imagine a busy shopping centre with automatic sliding and revolving doors serving as entry points. To ensure the safety of visitors and prevent potential pinch incidents, switch strips are installed on the automatic doors.
In this situation, switch strips are used to immediately respond to potential obstacles and ensure that the doors operate safely and efficiently.
How does it work?
- Obstacle Detection: The switch strips are mounted along the edges of the doors, forming a continuous monitoring system. When a person or object makes contact with the door edge, the pressure on the switch strip is detected by the embedded sensors.
- Immediate Response: Once the sensors detect the pressure, they immediately send a signal to the door's control system. The control system interprets this signal as a potential danger and immediately halts the door's movement.
- Safe Reversal: After the door's movement is stopped, it is immediately reversed to provide ample space for the person or object that activated the security system. This ensures that no pinching or injury occurs and that the person can safely pass through the door.
Benefits of switch strips in this scenario:
- Safety: Switch strips provide a crucial safety feature in a crowded environment, where the risk of pinching by automatic doors can be significant. They minimize the risk of accidents and injuries.
- Efficient Flow: Due to the rapid detection of obstacles and the immediate response of the doors, the flow of people in the shopping centre is improved. Doors that operate safely and reliably reduce congestion and ensure smooth passage.
Switch strips on rolling doors in a warehouse environment
Imagine a warehouse with large roller doors serving as crucial access points for goods movement. To ensure the safety of personnel and goods, switch strips are installed on the roller doors.
In this situation, switch strips are used to detect potential pinch hazards and ensure that the roller doors operate safely and reliably, even during intense activity and rapid goods flows.
How does it work?
- Obstacle Detection: The switch strips are mounted along the edges of the roller door, continuously monitoring the door's movement. When a person, vehicle, or object makes contact with the switch strip, the pressure on the sensors is detected.
- Immediate Response: Once the sensors detect the pressure, they immediately send a signal to the roller door's control system. The control system interprets this signal as a potential danger and immediately halts the roller door's movement.
- Safe Stop and Reversal: After the roller door's movement is stopped, it is immediately reversed to provide ample space for the person, vehicle, or object that activated the switch strip. This prevents pinching, damage to goods, and injuries, ensuring the safety of personnel working near the roller door.
Benefits of switch strips in this scenario:
- Personnel Safety: Switch strips provide a crucial safety measure to prevent pinch hazards. They detect immediately when someone or something comes into contact with the door, minimizing the risk of injury and ensuring personnel safety.
- Goods Protection: The use of switch strips prevents goods from becoming trapped between the roller door and other surfaces. This helps to keep goods intact and prevents damage to valuable items.
- Door Reliability: By using switch strips, the reliability and durability of roller doors are improved. They help prevent mechanical failures.
Switching frames on Sliding and Folding Gates in Logistics Companies and Business Parks
Parking lots and industrial areas are often secured with fences, automatic sliding gates, and cameras. The continuous flow of freight demands seamless operation of these gates. To ensure the safety of employees and prevent potential pinching incidents, switch strips are installed on the gates.
Switch strips are attached to the closing edges of the sliding and folding gates. These are equipped with sensitive sensors that react immediately upon contact with an obstacle, be it an object or a person. When this pressure is detected, the switch strip immediately sends a signal to the gate's control system.
The control system interprets this signal as a danger and immediately halts the gate's movement. It then ensures that the gate moves in the opposite direction, preventing the obstructing object or person from getting trapped. This mechanism is essential to prevent incidents where vehicles or individuals get caught by the gate.
Benefits of switch strips in this scenario:
- Switch strips minimize the risk of pinching.
- By quickly responding to obstacles, switch strips help improve the flow of goods and vehicles.
Switch strips on sliding and folding gates
Control unit for gear shifters, safety mats and bumpers
When the sensor is activated or in case of cable interruption, the resistance changes to 1k2 and 8k2. Regardless of the principle applied, the control unit stops the machine or installation.
In addition, Mayser has control units suitable for 4-wire sensor connection.