Safety applications

Guarding of points of operation

Guarding of points of operation

Requirement:

The point of operation at a machine or system is to be guarded by an electro-sensitive protective device. The necessary distance between the protective device and point of operation is to be as small as possible.

 

Solution:

The safety light curtains of the MLC series with various resolutions ranging from 14 to 40 mm offer reliable finger and hand detection. This allows small safety distances between the safety sensor and the point of operation to be realized.

Guarding of points of operation with reach‑under and step‑behind protection

Requirement:

Access to the point of operation is to be guarded by means of a safety light curtain. If this sensor can be reached under or stepped behind, then a further safety light curtain is required in order to detect these situations.

 

Solution:

The cascadable MLC 520 and MLC 520-S safety light curtains allow up to 3 segments to be linked together. They are integrated in the control via a common connection. This makes installation easy and cost‑effective.

Guarding of points of operation with permissible objects in protective field

Requirement:

Guarding of the point of operation must detect violation of the protective field. Fixed or moving machine parts or work pieces inside the protective field, however, are to be permitted and must not cause a shutdown.

 

Solution:

The MLC 530 safety light curtains feature the fixed blanking, floating blanking and reduced resolution functions. These functions can be configured so that certain objects are permitted inside the protective field.

Guarding of foot space on side-tracking shelves

Requirement:

While the side-tracking shelf is moving, the foot space is to be monitored for the presence of persons. If multiple shelf rows are installed one behind the other, there must be no interference between the sensor signals of the rows.

 

Solution:

The SLS 46C single light beam safety devices monitor the foot space over a length of up to 70 m. They are available as a type 4 variant and as a particularly easy‑to‑align type 2 variant. The use of models with red light and infrared light prevents mutual interference between the shelf rows.

Guarding of narrow openings

Requirement:

If it is possible to reach through a narrow opening into an area where a hazardous movement takes place, then this opening must be guarded to prevent access.

 

Solution:

The single light beam safety devices SLS 46C are used for small openings. They are available as type 2 and type 4 variants and can be integrated easily using connectors or cables.

Access guarding

Access guarding

Requirement:

Access to a dangerous area at a machine or system is to be guarded. To enable simple entry and exit of material, optoelectronic safety sensors are to be used.

 

Solution:

The MLD 300/500 multiple light beam safety devices offer affordable access guarding solutions. The transceiver models with an operating range of up to 8 m are especially easy to install. For wide-area guarding, transmitter/receiver models are available with a range of up to 70 m.

Multi-sided access guarding

Requirement:

Access to the working range is to be guarded while the machine is in operation. To enable material entry and exit, the machine must be easily accessible from multiple sides.

 

Solution:

The MLD 300/500 multiple light beam safety devices in combination with the UMC mirror columns safeguard access to the machine on multiple sides and over lengths of up to 70 m. The integrated laser alignment aid makes installation quick and easy.

Access guarding using sensors outside of working range

Requirement:

Access to dangerous areas by persons and vehicles is to be monitored using safety sensor technology. The sensors must not hinder free movement within the working range.

 

Solution:

The RSL 400 safety laser scanner is installed above the access area and the protective field is aligned vertically. This ensures that the working range is not restricted. By using two safety functions working in parallel, one RSL 400 can monitor two stations simultaneously and independently from each other.

Access guarding on conveyor lines, with muting function

Requirement:

Access guarding on conveyor lines is to prevent persons from accessing the danger zone, while at the same time allowing the transported goods to pass through.

 

Solution:

The muting function bridges the safety sensor in a controlled manner to allow the transported goods to pass through. This function is already integrated in the MLD 300/500 multiple light beam safety devices and the MLC 500 safety light curtains. The MSI-MD-FB muting interface and MSI 400 safety control provide an external muting control.

Access guarding on conveyor lines, with Smart Process Gating

Requirement:

Access guarding on conveyor lines is to prevent persons from accessing the danger zone, while at the same time allowing the transported goods to pass through.

 

Solution:

With Smart Process Gating, the safety sensor is bridged by means of a control signal from the PLC. The function is integrated in the MLC 530 SPG safety light curtain. Additional muting sensors are not required and, owing to SPG, the systems have low space requirements.

Area guarding

Guarding of hazardous areas

Requirement:

The hazardous working range of the machine is to be guarded against entry by and the presence of persons. The contour of the monitored area is to be adapted to the contour of the machine.

 

Solution:

The RSL 400 safety laser scanners use configurable protective fields for area monitoring. Thanks to the 8.25 m operating range and 270° scanning range, large areas can be guarded with just one device.

Restart protection and monitoring of hidden areas

Requirement:

To prevent danger, the process is not permitted to restart until it has been ensured that no persons are in the work area or in the hidden area.

 

Solution:

The RSL 400 safety laser scanners monitor the presence of persons with a configurable protective field. The LBK 3D safety radar system is used under harsh ambient conditions and also allows the presence of static objects in the monitored area.

Guarding of hazardous areas in harsh environments

Requirement:

The hazardous working range of the machine is to be guarded against entry by and the presence of persons. Safe operation and high availability must also be guaranteed under harsh ambient conditions – such as dirt, welding sparks, sawdust or humidity.

 

Solution:

The LBK 3D safety radar system detects movements in the monitored area and operates reliably even under harsh ambient conditions. Furthermore, the radar technology allows the presence of static objects in the monitored area.

Guarding and navigation of automated guided vehicles (AGVs)

Requirement:

The transportation path of the AGV must be guarded by means of safety sensors. The protective fields are to be flexibly adapted to the movement and loading situation. If the principle of natural navigation is used, the device is at the same time to provide the measurement data for the navigation software.

 

Solution:

The RSL 400 safety laser scanner merges safety technology and high-quality measurement value output in a single device. It has a scanning range of 270° and 100 reversible field pairs. Two scanners therefore provide optimum guarding of the AGV. The measurement data has a high angular resolution of 0.1° and a low measurement error.

Guarding of physical safety guards

Monitoring of doors and flaps

Requirement:

Moving protective devices such as doors and flaps protect the operator from hazards. The closed state of the protective devices must be monitored.

 

Solution:

The safety switches of the S20/200 series with their robust housings and wide range of installation options can be used universally. The contactless, magnetically coded switches of the MC series are ideal for use in harsh, dirty or damp environments.

Monitoring of doors and flaps, with high protection against manipulation

Requirement:

The closed state of safety guards such as doors or flaps must be monitored. EN ISO 14119 stipulates that measures to protect against manipulation must also be provided. If this is not possible through constructive measures, the sensor must have a high level of protection against manipulation.

 

Solution:

The RD 800 contactless safety transponders with RFID coding offer maximum protection against manipulation. With their OSSD outputs, they are also easy to integrate in the safety circuit.

Monitoring of doors and flaps with locking device, for long stopping times

Requirement:

Areas with hazardous movements can be entered via safety doors to allow maintenance. If the movement does not stop immediately after the door is opened, the door is to be guarded by a safety switch with locking device.

 

Solution:

The robust L series safety switches with locking device keep safety doors securely locked until access is released by an electric signal. The series includes standard designs, devices with integrated operational controls as well as devices with RFID‑coded actuators.

Monitoring of doors and flaps, with locking device for process protection

Requirement:

When doors or flaps are opened, the process is allowed to stop only at defined positions in order to avoid scrap or maintenance work when the process starts up again. The doors or flaps are to be released only when these positions are reached.

 

Solution:

The L series safety switches with locking device keep safety doors locked until the process control sends an electric release signal.

Safe monitoring of final positions

Requirement:

To trigger shutdown at the end of the cutting process or for service work, it is necessary to monitor when the saw blade reaches the final position.

 

Solution:

The S300 position switch monitors when the final position is reached. Variants with plunger and various actuators make the device suitable for universal use. With its forced normally closed contacts, the S300 can also be directly integrated into the safety circuit.

Triggering of an emergency stop

Requirement:

Machines and systems with dangerous movements must be equipped with an E‑Stop device. This device can be actuated manually in the event of danger.

 

Solution:

The ESB 200 E‑Stop button is used wherever it makes sense to be able to enter a stop command at a specific location. The ERS 200 E‑Stop rope switch is used for larger danger zones.

Evaluation of safety sensors by safe control components

Evaluation of individual safety sensors

Requirement:

For correct execution of the safety function, safety sensors must be integrated into the machine circuit using safe control components in accordance with the requirements defined in EN ISO 13849-1.

 

Solution:

With the reliable MSI safety relays, individual safety sensors can be integrated quickly and easily into the safety circuit of machines and systems. Depending on the model, the relays are tailored to specific applications or can be used universally.

Evaluation of multiple safety sensors with configurable safety functions

Requirement:

Multiple safety sensors must be integrated into the machine or system control. Functions such as a time delay for releasing a locking device or signal connections are also to be configured.

 

Solution:

The basic module of the MSI 400 expandable safety control already has 24 safe inputs/outputs as well as an Ethernet interface with Industrial Ethernet protocols. The safety control can be configured quickly and efficiently using the license‑free configuration software MSI.designer.

Safe movement monitoring (Safe Motion)

Requirement:

To protect employees during maintenance and setup activities, dangerous movements must be reliably monitored. To protect machines and processes, upper and lower limit values – e.g. for speeds – must not be exceeded during operation.

 

Solution:

With the MSI 400 safety control, the inputs for safe movement monitoring are already integrated in the base module. It monitors the pulses from sensors with respect to the limits required for safe operation, e.g. for speed, angle, position and direction information.