FIELD: instrumentation.
SUBSTANCE: invention relates to technological devices and can be used as a part of an automated measuring system together with measuring instruments at control of feed circuits of an electrotechnical system of items in the process. A switching unit includes three input circuits, four output circuits, electromagnetic relays containing contacts and control windings, and control inputs connected to the control windings, and two resistors R1 and R2, and a diode. The relays are combined in two groups. Control circuits of each relay group are connected to each other and to control inputs of the relays. The first input circuit is intended for connection to a “plus” power bus of the item and connected to the first break-make contact (BMC) of the first contact group (FCG). The second input circuit is intended for connection to a “minus” power bus of the item and connected to the second FCG BMC. The third input circuit is intended for connection to the housing of the item and connected to the third FCG BMC and the second contact group (SCG). The first output circuit is intended for connection of the first output of the measuring instrument and is connected to the first normally closed contact (NCC) of SCG. The second output circuit is intended for connection of the second output of the measuring instrument and is connected to the second NCC of SCG. The first NCC of FCG is connected to the first SCG BMC. The second NCC of FCG is connected to the second SCG BMC. The first normally open contacts (NOC) of FCG and SCG are connected to one output of the first resistor R1. The second NOC of FCG and SCG are connected to one output of the second resistor R2. Other outputs of the above resistors are connected to the fourth BMC of FCG and SCG. The third NOC of FCG and the fourth NOC of SCG are connected to the third output circuit intended for connection of the first output of the second measuring instrument. The third NOC of SCG and the fourth NOC of FCG are connected to the fourth output circuit intended for connection of the second output of the second measuring instrument. A diode cathode is connected to the first output circuit, and a diode anode is connected to the second output circuit.
EFFECT: improvement of efficiency.
2 cl, 1 dwg
