Elevator Safety System Bus Node Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Elevator systems lack assurance of safe operation when temporary participants, such as manual control devices or governor elements, are connected or disconnected, as existing safety systems do not clearly ensure safety during these operations.
Innovation Solution
A safety system with a control unit, bus, and bus nodes that requires at least one temporary participant to be connected for safe operation, with a structured management system that includes a target list for participant identification and mode switching, ensuring safe working practices by enabling specific operating modes only when authorized participants are connected.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If temporary participants are connected to the bus for maintenance or configuration operations, then the ease of operation is improved, but the reliability of safe operation deteriorates due to uncertainty about safety assurance
Solution Approach 1:
The control unit continuously monitors the connection status of temporary participants on the bus and provides feedback by enabling or disabling operating modes based on which temporary participant is connected. This ensures that only authorized operations can be performed while maintaining ease of operation for maintenance and configuration tasks.
Solution Approach 2:
The safety system dynamically adjusts its operational state based on the connection status of temporary participants. The control unit enables specific operating modes (maintenance mode, configuration mode) only when the corresponding temporary participant is detected on the bus, creating a dynamic safety mechanism that adapts to current operational needs while ensuring reliability.
2Reliability
If the safety system requires specific temporary participants to be connected for different operating modes, then the reliability is improved, but the device complexity increases due to structured management requirements
Solution Approach 1:
The bus-based communication system serves multiple functions: it communicates between control units and participants, monitors connection status of temporary participants, and triggers mode changes. This multi-functionality reduces the need for separate dedicated circuits for each safety function, thereby managing complexity while maintaining high reliability.
Solution Approach 2:
The control unit automatically detects which temporary participant is connected to the bus and self-configures the appropriate operating mode without requiring external intervention or complex manual switching. The system serves itself by monitoring bus participants and enabling corresponding modes, which improves reliability while keeping the control logic manageable.
3Reliability
If the control unit monitors bus participants to enable specific operating modes, then the reliability of safe operation is improved, but the loss of time increases due to continuous monitoring requirements
Solution Approach 1:
The bus-based communication system continuously monitors participant connections as part of its normal operation, rather than requiring separate periodic checks. This continuous monitoring is integrated into the existing communication protocol, ensuring reliability without adding significant time loss since the monitoring occurs concurrently with regular bus communications.
Data Source
AI summary
A method for operating a safety system including a control unit, a bus, a plurality of bus nodes connected to the control unit via the bus, and a plurality of participants connected to the control unit via the bus nodes, wherein at least one participant is designed as a temporary participant. The method includes the step of enabling the safety system for operation by the control unit when either a first temporary participant or a second temporary participant is connected to the bus. An elevator system can be provided with a safety system for carrying out the method.