Patent ID: 11914002
Assignee: CROUZET AUTOMATISMES
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. An electrical installation comprising:
a first and a second power supply cable respectively connected to a first and a second different potential of a power supply source;
a measurement cable, the first and second power supply cables and the measurement cable being housed inside one or more cable harnesses;
a sensor capable of measuring a physical quantity, this sensor comprising:
a first and a second power supply terminal respectively connected to the first and to the second power supply cables;
an output terminal connected to the measurement cable; and
a transducer powered by means of the first and second power supply terminals of the sensor, this transducer being capable of converting the measured physical quantity into a corresponding electric signal; and
the sensor is capable of delivering, on its output terminal, an analog electric signal coding the measurement of the physical quantity using a corresponding value of a potential or of the intensity of a current, the value of the electric signal delivered on the measurement cable systematically being within a predetermined measurement range when the transducer operates correctly;

an electronic computer comprising:
a first and a second power supply terminal respectively connected to the first and to the second potentials of the power supply source;
an input terminal connected to the measurement cable;
an analog-digital converter connected to the input terminal in order to convert the analog electric signal present on the input terminal into a digital signal; and
a microprocessor programmed to:
control an item of electrical equipment as a function of the value of the digital signal if this digital value corresponds to a value of the analog electric signal within a predetermined measurement range; and, alternatively
indicate an interrupted state of the first power supply cable if the value of the digital signal corresponds to a first predetermined fault value located outside any predetermined measurement range;

a monitoring module positioned between the power supply terminals of the sensor and the first and second power supply cables, this monitoring module being capable of generating, on the measurement cable, the first predetermined fault value in response to the interruption of the first power supply cable;
wherein the monitoring module comprises a first transistor comprising a first and a second power electrode and a control electrode, this first transistor being capable of switching, as a function of a control signal received on the control electrode thereof, between:
an open state, in which the power electrodes thereof are electrically isolated from each other; and
a closed state, in which the power electrodes thereof are electrically connected together;

the first and the second power electrodes of the first transistor being electrically connected to the second power supply cable and to the measurement cable, respectively, so that, when the first transistor is in the closed state thereof, the first predetermined fault value is generated on the measurement cable, and the control electrode is connected to the first power supply cable, so that a loss of current on the first power supply cable, caused by the interruption thereof, automatically triggers the switching of the first transistor to the closed state thereof and so that, alternatively, the absence of interruption of the first power supply cable keeps the first transistor in the open state thereof; and
wherein the monitoring module further comprises:
a first resistor connected in series with the first power supply cable;
a second transistor comprising a first and a second power electrode and a control electrode;
the first power electrode and the control electrode of the second transistor being connected to the first power supply cable, each on a respective side of the first resistor, so as to automatically trigger the switching of the second transistor to the open state thereof in response to an interruption of the first power supply cable and to keep this second transistor in the closed state thereof in the absence of an interruption of the first power supply cable;
the control electrode of the first transistor being connected, on the one hand, to the second power electrode of the second transistor and, on the other hand, to the second power supply cable by means of a second resistor, so as to generate a control signal that triggers the switching of the first transistor to the closed state thereof only when the second transistor switches to the open state thereof.