Technical data
Application	Emergency stop, Light barrier
Cat. / PL acc. to EN ISO 13849-1	4/e
SIL CL acc. to IEC/EN 62061	3
SIL acc. to IEC/EN 62061	3
Safe output contacts, redundant NO contacts	2, 3
Width	45 mm
Type	BH 5911
Variant
Contact equipping	3 NO contacts
Nominal voltage	DC 24 V
Approvals and Markings	CSA C/US, TÜV, CCC

The Dold BH5911.03/00MF0 DC24V is a base module of the modular safety system SAFEMASTER M, designed for implementing safety-related control circuits in industrial applications. It is particularly used for the safe control of emergency stop functions and light curtains, with safety functions realized via mechanical relay contacts and electronic monitoring. The device is intended for use in machine and plant engineering, where high safety integrity is required, for example in the paper and printing industry, forming technology, or food packaging. The module width is 45 mm, enabling compact installation in standard control panels.

Applications
This module is used in systems where personnel and machine safety are paramount. It is suitable for applications such as emergency stop circuits, light curtains, safety doors, or two-hand controls in accordance with EN 574. Its functionality includes monitoring of inputs such as start or stop buttons and emergency stop circuits, with system configuration performed via selector switches. The modular architecture allows flexible adaptation to different safety tasks without requiring special programming.

Functions and Equipment in Detail
The device features 3 normally closed contacts as output contacts, designed for safety-related applications. The contact configuration allows realization of up to two emergency stop circuits, with switching between single-channel and dual-channel operation. The outputs can also be used for an emergency stop circuit with additional stop function or for auto/manual start. Functions are configured using internal switches adjusted with a screwdriver, enabling simple commissioning without special tools or software. Two semiconductor outputs serve as status indicators and enable diagnosis of the system state.

Technology Explained Simply
The module operates at a nominal voltage of DC 24 V and is designed for industrial environments. It includes over- and under-voltage monitoring, which triggers a fault indication if the nominal voltage deviates. Additionally, a continuously monitored feedback circuit is provided to monitor the status of external contactors. Wire break and short-circuit monitoring ensures that open or shorted lines are detected and signaled, enhancing the reliability of the safety system. LEDs and semiconductor alarm outputs enable visual and electronic status indication.

Compatibility and Accessories
The base module is part of the SAFEMASTER M system and can be combined with other modules to realize complex safety functions. System components can be hierarchically grouped and flexibly interconnected. An optional fieldbus interface enables transmission of system status to other bus participants, supporting integration into existing automation systems. The modular architecture is expandable, allowing additional input or output modules to be connected.

Mounting and Installation
The module is mounted in standard control panels and requires no special mounting conditions. The module width of 45 mm corresponds to the standard for DIN rail mounting. Wiring is done via screw terminals, with input and output assignments configured via internal selector switches. Configuration is factory preset but can be adjusted on-site using selector switches.

Operational Advantages
The module offers high safety integrity with Performance Level (PL) e and Category 4 according to EN ISO 13849-1 as well as SIL 3 according to IEC/EN 62061. These certifications guarantee high reliability in hazard avoidance. The software-free configuration reduces programming and maintenance effort. Diagnostic functions via LEDs and semiconductor outputs simplify fault detection. The modular design enables flexible expansion and adaptation to different requirements.

Certifications and Markings
The device carries certifications CSA C/US, TÜV, CCC, confirming compliance with international safety standards. These certifications apply to use in industrial safety systems and ensure adherence to relevant safety requirements.

Safety Functions
The safety functions include monitoring of emergency stop circuits, start and stop buttons, and the option to choose between immediate and delayed shutdown. The redundant contact configuration (2 or 3 safe normally closed contacts) increases system fault tolerance. Functions are switchable via selector switches, enabling flexible use in various application scenarios.

System Integration
The module can be integrated into existing automation systems, especially when using a fieldbus interface. System messages can be transmitted to other controllers via the optional fieldbus connection, supporting visualization and diagnostics during operation. The modular expandability enables step-by-step realization of complex safety functions.

Application Scenarios
The module is used in systems where personnel and machine safety are paramount. It is suitable for applications such as emergency stop circuits, light curtains, safety doors, or two-hand controls in accordance with EN 574. Its functionality includes monitoring of inputs such as start or stop buttons and emergency stop circuits, with system configuration performed via selector switches. The modular architecture allows flexible adaptation to different safety tasks without requiring special programming.

Certifications and Markings
The device carries certifications CSA C/US, TÜV, CCC, confirming compliance with international safety standards. These certifications apply to use in industrial safety systems and ensure adherence to relevant safety requirements.

Safety Functions
The safety functions include monitoring of emergency stop circuits, start and stop buttons, and the option to choose between immediate and delayed shutdown. The redundant contact configuration (2 or 3 safe normally closed contacts) increases system fault tolerance. Functions are switchable via selector switches, enabling flexible use in various application scenarios.

System Integration
The module can be integrated into existing automation systems, especially when using a fieldbus interface. System messages can be transmitted to other controllers via the optional fieldbus connection, supporting visualization and diagnostics during operation. The modular expandability enables step-by-step realization of complex safety functions.

Application Scenarios
The module is used in systems where personnel and machine safety are paramount. It is suitable for applications such as emergency stop circuits, light curtains, safety doors, or two-hand controls in accordance with EN 574. Its functionality includes monitoring of inputs such as start or stop buttons and emergency stop circuits, with system configuration performed via selector switches. The modular architecture allows flexible adaptation to different safety tasks without requiring special programming.