FR2787195A1 - Device for measurement of operating data relating to equipment used in generation of dry air supply for over-pressurizing telephone cables by use of existing equipment used in monitoring the cables themselves - Google Patents

Abstract

The invention uses existing equipment used for monitoring the data relating to the cables themselves to also monitor the equipment used in pressurizing the cables. It involves using the response mode of the pressure transducers, in current modulated mode and the actual tele-surveillance system. The current modulation is within a twisted pair line.

Description

1 2787195

  DEVICE FOR MEASURING DATA OF EQUIPMENT

PRESSURIZATION

  The present invention relates to devices which make it possible to acquire the operating data of pressurization equipment for telephone cables. Reminders: The pressurization equipment (101) is designed to produce dry compressed air in sufficient quantity to maintain an overpressure in the cables

telephone (110).

  A remote monitoring system (114) is installed in each piece of equipment making it possible to control the pressures and

  the flow rates of each pressurized cable.

  Information specific to the pressurization equipment is not monitored. The system described by the present invention allows this

  missing, without modification of the remote monitoring system.

  The pressurization equipment (101) consists of a compressor C (102) which compresses air at a pressure P1 (111), the compressed air passes through a dryer system S (103), the dry air is then controlled by a hygrometer H (104), then relaxed (105) to a pressure P2 (112) and stored in a tank R (106). Then the compressed air is again expanded (105) to a pressure P3 (113) to be distributed to the telephone cables to be pressurized

(110).

  Each cable connected to the pressurization system therefore receives a pressure P3, which propagates along the cable, warning by monitoring the holding flow and the pressures measured along the cable, of a failure thereof, at the level of its envelope (wear,

2 2787195

  accident,..). The flow and pressure measurements of each cable are ensured by a remote monitoring system (114) which

  is interrogated by supervision software (115).

  The present invention, SME equipment measurement system (100), allows, without modification of the remote monitoring system (114), to monitor, in addition, the operating parameters of the pressurization equipment (compressor, humidity, pressures, flow rate

  total) which are not taken into account at the moment.

Description:

  The advantages of the invention appear clearly

  in the following description, presented by way of example

  not limiting with regard to the appended figures which present: FIG. 1, a schematic view of a pressurization equipment for telephone cables currently in service (several thousand), the invention (100) is shown there symbolically connected to the monitored devices, - Figure 2, a schematic view of the invention, - Figure 3, a schematic view of the connections of the remote monitoring system to the pressure transducers and to the invention, - Figure 4, the principle of interrogation - response between remote monitoring and pressure transducers

or the invention.

  In FIG. 1, the compressor C (102) operates autonomously. One of the characteristics of the invention is to quantify this operation by measuring the compressor energizations, in time and in number. Another characteristic of the invention is to be able to monitor the outlet pressure of the compressor! MI - iIff

3 2787195

  in order to check its proper functioning.

  Current pressurization equipment is equipped with a device for measuring the humidity, or dew point, H (104), the function of this device is to alarm if a threshold is exceeded, another characteristic of the invention is to be able to continuously monitor the humidity measurement in order to deduce a trend, making it possible to intervene before the alarming by

exceeding the threshold.

  Another characteristic of the invention is to be able to monitor the pressure available in the tank R (106), by a P2 sensor (112), as well as the total flow

  D (108) by an appropriate flow meter.

  Another characteristic of the invention is to be able to measure the operating pressure P3 (113). By measuring these three data (P2, D, P3) and knowing the volume of the tank R, we can deduce the autonomous operating time in case of failure of the compressor C. Another characteristic of the invention is to connect without modification, on a free way of the remote monitoring system (114), making it accessible remotely

  all the data thus measured by the invention.

  In FIG. 2, a representation, given by way of example, of the invention broken down as follows: - an isolated supply (121) makes it possible to operate the invention from the energy present in the pressurization equipment , - a microprocessor-based central unit (129) is responsible for ensuring all the control, measurement and response functions of the invention, - the compressor is monitored by means of a

  opto-isolator (122), connected in parallel to the motorbike

--- - RF -r TM

4 2787195

  compressor, - the analog measurements (123) coming from the sensors either at 4-20mA, or at 0-5 / 10V voltage, are provided by the controller (129), the response, explained below, is provided by a synthetic generator sinusoidal (126) through two opto-isolators, one detecting the request (125) and the other (124) modulating a current towards the remote monitoring (114), - indicators (128), indicate the state of the invention (operation, test, response), - test inputs (130), allow rapid control of the proper functioning of the assembly, a connector (127) is provided to ensure local display of the measured data and / or a extension

  features of the invention.

  Figure 3 shows in 3.a, the connection of the remote monitoring (114) to a measurement line (131) of pressure transducers (136) and in 3.b, the connection

  from remote monitoring to the invention (100).

  One of the characteristics of the invention is to behave, in its response to the remote monitoring system (114), like a line of 16 pressure transducers (136), in no way modifying the remote monitoring systems, which are intended to scan from 20 to 100 measurement lines (131) of pressure transducers, the

  connection to the invention being made on a free way.

  Figure 4.a shows a typical response timing diagram when interrogating a line of transducers

  (136), all connected in parallel on the same line (131).

  The remote monitoring system, to interrogate a line (131), transmits at a time t0 a potential U at the terminals of the line, all the transducers present on this line, start up and respond by modulating the current i by 1 -I - f- '

2787195

  loop (132) of the line, sequentially in time (134) one after the other, according to a code n which has been assigned to them: 1, 2, ... 15, 16, corresponding to a delay tn in

the time of tO + 2n seconds (4.b).

  Figure 4.b shows the detail of one of the responses (133) in current (132) from a time position (134). Each response must be 2 seconds apart and last 1.5

  second, leaving a 'blank' between each response.

  Figure 4.c shows the form of a current response (133). The modulation is sinusoidal and is characterized by a modulation current (i mod), a maximum (i max), and a frequency f (135) which contains the analog measurement of pressure of the transducer (136) during response,

  according to the formula P = f mb (eg 1450Hz = 1450mb).

  The remote monitoring system (114) examines, in turn, the measurement lines, checks the validity of the responses, stores the measurements of each transducer and transmits them, on request, to a supervision system.

  (115) which centralizes several pressurization sites.

  One of the characteristics of the invention is to use the response principle of the pressure transducers (136) to communicate its data to the remote monitoring system. The invention is connected to a free measurement line (131) of the remote monitoring system (114). The invention detects that the line is energized, and then begins to respond by modulating the current, sequentially, by

  taking into account the characteristics explained above.

  Each time modulation (134) corresponds to data acquired by the invention (compressor pressure, humidity, tank pressure, total flow, operating pressure, total compressor operating time, number of starts

compressor).

6 2787 195

  One of the characteristics of the invention is the coding of the response frequency for transmitting data

digital and analog.

  One of the characteristics of the invention is to use several response positions to transmit certain

digital data.

1 A- 1

7 2787195

Claims (15)

  1. Device for measuring data from cable pressurization equipment (101) by response to the remote monitoring system (114) in current modulation (132) a two-wire line (131).   2. Device according to claims 1, characterized   by a current modulation comprising several data consecutive (134).   3. Device according to claims 1, characterized in   what the frequency of the current modulation (135) contains digital data.   4. Device according to claims 1, characterized in   what the frequency of the current modulation (135)   contains fixed frequency hops.   5. Device according to claims 1, characterized in   what several answers (133) can constitute one only digital data.   6. Device according to claims 1, characterized in   what the frequency of the current modulation (135) contains analog measurements.   7. Device according to claims 1, characterized in   that each response in current modulation is   2 seconds from the previous one. 3 11 1i - 1l11 8 2787 195   8. Device according to claims 1, characterized in   that the device is isolated (124) from the remote monitoring system.   9. Device according to claims 1, characterized in   that the device is isolated (121) from the energy of pressurization equipment.   10. Device according to claims 1, characterized   in that the device is isolated (122) from the compressor.   11. Device according to claims 1, characterized   in that the device powers and measures sensors industrial type 4-20mA (123).   12. Device according to claims 1, characterized   in that the device measures voltages 0 to 5 or 10V.   13. Device according to claims 1, characterized   in that the device counts the number of start-ups compressor.   14. Device according to claims 1, characterized   in that the device counts the total time of compressor operation.   15. Device according to claims 1, characterized   in that the device has an extension connector (127).