摘要:
A safety switching device comprises a position encoder, such as a potentiometer, for user selection of an operational quantity, such as an operating mode. The position encoder has a first terminal, a second terminal, and a tap moveable through a plurality of positions. A total impedance is defined between the first terminal and the second terminal. A first partial impedance is defined between the first terminal and the tap, and a second partial impedance is defined between the tap and the second terminal. An arrangement for determining an instantaneous position of the tap comprises a first evaluation circuit designed to determine a first measurement value representative of the first partial impedance, and a second evaluation circuit designed to determine a second measurement value representative of the second partial impedance. At least one from the first and second evaluation circuits is designed to determine the instantaneous position of the tap by means of the first and second measurement values.
摘要:
A safety switching device comprises a position encoder, such as a potentiometer, for user selection of an operational quantity, such as an operating mode. The position encoder has a first terminal, a second terminal, and a tap moveable through a plurality of positions. A total impedance is defined between the first terminal and the second terminal. A first partial impedance is defined between the first terminal and the tap, and a second partial impedance is defined between the tap and the second terminal. An arrangement for determining an instantaneous position of the tap comprises a first evaluation circuit designed to determine a first measurement value representative of the first partial impedance, and a second evaluation circuit designed to determine a second measurement value representative of the second partial impedance. At least one from the first and second evaluation circuits is designed to determine the instantaneous position of the tap by means of the first and second measurement values.
摘要:
A device for reliably monitoring a closed position of two parts which can move relative to one another has an actuator and a sensor. The device is particularly used for monitoring the closed position of a protective door installed for safeguarding a technical installation which operates in an automated fashion. The sensor has a receiver circuit at an input side, which circuit generates a defined receiver circuit signal when a switching distance between the sensor and the actuator is fallen short of. A detector circuit provides an enable signal when the defined receiver circuit signal is present. According to one aspect of the invention, a test element is provided for selectively suppressing the defined receiver circuit signal.
摘要:
A device for reliably monitoring a closed position of two parts which can move relative to one another has an actuator and a sensor. The device is particularly used for monitoring the closed position of a protective door installed for safeguarding a technical installation which operates in an automated fashion. The sensor has a receiver circuit at an input side, which circuit generates a defined receiver circuit signal when a switching distance between the sensor and the actuator is fallen short of. A detector circuit provides an enable signal when the defined receiver circuit signal is present. According to one aspect of the invention, a test element is provided for selectively suppressing the defined receiver circuit signal.
摘要:
A safety switching apparatus for failsafe disconnection of an electrical load has a first and a second connecting terminal for connecting a first signaling switch and a third and a fourth connecting terminal for connecting a second signaling switch. It also has a first and a second output switching element, which are designed to produce a redundant output switching signal. The first connecting terminal is connected to a first potential and the third connecting terminal is connected to a second potential. The potentials differ from one another. In addition, the second connecting terminal is coupled to the first switching element in such a way that the first switching element receives the first potential via the first signaling switch. Likewise, the fourth connecting terminal is coupled to the second switching element in such a way that the second switching element receives the second potential via the second signaling switch. According to one aspect of the invention, a circuit arrangement is provided for determining at least one further potential at the second and/or fourth connecting terminal, and said circuit arrangement is designed to control the redundant output switching signal as a function of the further potential.
摘要:
The invention relates to a safety switching apparatus and to a method for safely switching on and off an electrical load, in particular an automated installation. The apparatus comprises a first port for a first signaling element, a second port for a second signaling element, a first switching device coupled to a first switching activator, and a second switching device coupled to a second switching activator. A time monitoring apparatus activates the first and the second switching activators only if a time between an actuation of the signaling elements is smaller than a predetermined maximum duration. The activation of the switching activators in turn causes the switching devices to be switched-through and thus the load to be switched on. For the activation of the switching activators, a first and a second switching element, which are each arranged in series with the switching activators, need to switched-through. According to one aspect of the invention, at least a first microcontroller is provided for the time monitoring, which microcontroller is designed to detect actuations of the signaling elements and to activate the switching elements in the event of the maximum duration being undershot.
摘要:
The invention relates to a safety switching apparatus and to a method for safely switching on and off an electrical load, in particular an automated installation. The apparatus comprises a first port for a first signaling element, a second port for a second signaling element, a first switching device coupled to a first switching activator, and a second switching device coupled to a second switching activator. A time monitoring apparatus activates the first and the second switching activators only if a time between an actuation of the signaling elements is smaller than a predetermined maximum duration. The activation of the switching activators in turn causes the switching devices to be switched-through and thus the load to be switched on. For the activation of the switching activators, a first and a second switching element, which are each arranged in series with the switching activators, need to switched-through. According to one aspect of the invention, at least a first microcontroller is provided for the time monitoring, which microcontroller is designed to detect actuations of the signaling elements and to activate the switching elements in the event of the maximum duration being undershot.
摘要:
A safety switching apparatus for failsafe disconnection of an electrical load has a first and a second connecting terminal for connecting a first signaling switch and a third and a fourth connecting terminal for connecting a second signaling switch. It also has a first and a second output switching element, which are designed to produce a redundant output switching signal. The first connecting terminal is connected to a first potential and the third connecting terminal is connected to a second potential. The potentials differ from one another. In addition, the second connecting terminal is coupled to the first switching element in such a way that the first switching element receives the first potential via the first signaling switch. Likewise, the fourth connecting terminal is coupled to the second switching element in such a way that the second switching element receives the second potential via the second signaling switch. According to one aspect of the invention, a circuit arrangement is provided for determining at least one further potential at the second and/or fourth connecting terminal, and said circuit arrangement is designed to control the redundant output switching signal as a function of the further potential.
摘要:
A safety switching apparatus for safe disconnection of an electrical load has at least one input for connecting a signaling device. The safety switching apparatus further has an evaluation and control unit and at least one switching element which can be controlled by the evaluation and control unit in order to interrupt an electrical power supply path to the load. The evaluation and control unit is designed to carry out functional tests at defined instances of time in order to check at least one switching function of the at least one switching element. Moreover, the at least one input for connecting the signaling device is further designed as an input for supplying a supply voltage required for operation of the at least one switching element.
摘要:
A safety switching apparatus for safe disconnection of an electrical load in an automated installation has at least one input for connecting a signaling device. The safety switching apparatus has an evaluation and control unit and at least one switching element controlled by the evaluation and control unit in order to interrupt an electrical power supply path to the load. The switching element is a changeover switch having at least two mutually alternative switching paths, with a first switching path being located in the electrical power supply path to the load and with a second switching path leading to a monitoring unit.