Plug connector
In a plug connector for connecting a field device of automation technology to an energy supply and/or to an evaluation unit, the plug connector includes a connection plug (M 12 ) for the field device, wherein the connection plug (M 12 ) is composed, at least partially, of a transparent material, wherein at least four display elements (gn ye, ye, rd) are arranged in the connection plug (M 12 ). A first display element (gn) signals operational readiness of the field device; second and third display elements (ye, ye) signal two antivalent switch outputs (MIN, MAX) of the field device; and a fourth display element (rd) signals a disturbance or malfunction of field device. A circuit (NOR, XNOR) is provided to detect a disturbance or malfunction of field device based on the antivalent switch outputs (MIN, MAX) of the field device, and to activate fourth display element (rd) upon detection.
1. A plug connector for connecting a field device of automation technology to an energy supply and/or to an evaluation unit, comprising:
a connection plug for the field device, wherein said field device has two antivalent switch outputs respectively indicating a current switch state of the field device, and the connection plug is composed, at least partially, of a transparent material; and
at least four display elements, including a first display element, a second display element, a third display element, and a fourth display element, arranged in said connection plug, wherein:
the first display element is connected to indicate operational readiness of the field device;
the second display element and the third display element are respectively connected to indicate states of the two antivalent switch outputs of the field device,
wherein when no disturbance or malfunction occurs, the second display element indicates that a first one of the two antivalent switch outputs of the field device is in a first state and the third display element indicates that a second one of the two antivalent switch outputs of the field device is in a second state such that the antivalent switch outputs are in different states, and
wherein when a disturbance or malfunction occurs, the second and third display elements indicate that the two antivalent switch outputs are in a same state;
the fourth display element is connected to the two antivalent switch outputs by a NOR or XNOR logic circuit to signal a disturbance or malfunction of the field device; and
wherein the logic circuit is so embodied that a disturbance or malfunction of the field device is detected based on said antivalent switch outputs of the field device wherein in case that a disturbance or malfunction is detected, said fourth display element is also activated to provide a further indication that the two antivalent switch outputs are in the same state and that a disturbance or malfunction o the field device has occurred.
2. The plug connector as claimed in claim 1 , wherein:
said logic circuit is implemented in CMOS technology.
3. The plug connector as claimed in claim 1 , wherein:
said logic circuit is implemented with an integrated gate.
4. The plug connector as claimed in claim 1 , wherein:
said logic circuit is implemented in an integrated circuit chip.
5. The plug connector as claimed in claim 1 , wherein:
said logic circuit comprises a switch element, which is so embodied that in the case of occurrence of a disturbance or malfunction, which is detected based on said connected antivalent switch outputs, it activates said fourth display element, which is connected downstream.
6. The plug connector as claimed in claim 5 , wherein:
said switch element is a bipolar transistor, especially a PNP transistor, in whose base branch said second display element and said third display element are connected in parallel and in whose collector branch said fourth display element is arranged; and
aid bipolar transistor is so embodied that it blocks in normal operation and conducts in the case of occurrence of a disturbance or malfunction.
7. The plug connector as claimed in claim 1 , wherein:
said logic circuit is so embodied that said second display element and said third display element are connected in parallel and said fourth display element is connected in series with said second display element and said third display element, that in normal operation the voltage lying on a node between said two parallel connected display elements and said fourth display element is low that said fourth display element is deactivated, and that in the case of occurrence of a disturbance or malfunction the potential on the node is high that said fourth display element is activated.
8. The plug connector as claimed in claim 1 , wherein:
said display elements are light-emitting diodes;
the first light-emitting diode lights in a first color, preferably in green color, and characterizes the operating state of the field device;
the second and third light-emitting diodes light in a second color, preferably in yellow color, and display said two antivalent switch outputs; and
the fourth light-emitting diode lights in a third color, preferably in red color, and signals disturbance- and/or malfunction.
9. The plug connector as claimed in claim 8 , further comprising:
a Zener diode at least in an anode branch of said fourth light-emitting diode.