Safety Switching Apparatus Clock-Synchronized Current Boost
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Safety switching apparatuses face challenges with low input currents leading to increased susceptibility to disturbances and prolonged reaction times due to the complexity of short-circuit detection and evaluation, especially in redundant connection lines within multi-core cables.
Innovation Solution
A safety switching apparatus with a current-increasing circuit and a switching element that selectively increases input current in response to a clock reference, actively counteracting disturbances by synchronizing the current increase with the clock reference and only activating when necessary, thereby reducing error rates and reaction times.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If low input currents are used to reduce power loss, then power consumption is minimized, but the input becomes more susceptible to disturbances and error rates increase
Solution Approach 1:
The patent applies periodic action by cyclically increasing the input current at defined time instants rather than maintaining a continuously high current. The current-increasing circuit is activated periodically based on a clock reference signal, which allows the system to maintain low average power consumption while periodically enhancing signal evaluation capability to counteract disturbances and reduce error rates.
2Reliability
If input current is increased to reduce susceptibility to disturbances, then error rates decrease, but power consumption increases
Solution Approach 1:
The patent implements periodic action by activating the current-increasing circuit only at defined time instants based on a clock reference signal. This periodic activation allows the system to reduce error rates when needed while maintaining low average power consumption during periods when the enhanced current is not required.
Solution Approach 2:
The patent applies dynamics by making the input current adjustable and switchable between different levels. The current-increasing circuit with switching element dynamically modifies the input current based on operational requirements, allowing the system to adapt between low current (power-saving mode) and high current (disturbance counteraction mode).
3Reliability
If dynamic signals are used for short-circuit detection, then short-circuit detection capability is improved, but reaction time is prolonged due to additional signal evaluation steps
Solution Approach 1:
The patent applies preliminary action by cyclically increasing the input current in advance at defined time instants before potential disturbance evaluation. This proactive current enhancement ensures that when signal evaluation occurs, the input signals are already at optimal levels for accurate disturbance detection, thereby maintaining fast reaction times while preserving short-circuit detection capability.
Data Source
AI summary
A safety switching apparatus for switching-on or switching-off a technical installation has a first input for receiving a first clock signal via a feed line, said first clock signal having a first clock frequency. A failsafe control/evaluation unit processes the first clock signal in a failsafe manner in order to generate an output signal for switching-on or switching-off the technical installation in response to the first clock signal. A clock reference provides a second clock signal having a second clock frequency. A current-increasing circuit having a switching element is arranged for selectively increasing an input current into the first input. The switching element is coupled to the clock reference and selectively activates or deactivates the current-increasing circuit in response to the second clock frequency.