DE20301168U1 - Monitoring system for fluid gas tanks has pressure and content sensor and wireless connection to central office - Google Patents

Abstract

A monitoring system for fluid gas fuel tanks comprises a sensor to determine tank parameters such as contents and supply pressure and an electronic control connected to a central office by wireless data communication. The system is locally powered by natural energy, such as a solar module (3), with an energy store (4).

Description

Propane Rheingas GmbH & Co. KG,
Fischenicherstraße 23, 50321 Brühl

"Order for monitoring liquefied gas tanks"

The innovation concerns an arrangement according to the preamble of claim 1.

Such arrangements are known from practice. They establish a data connection via a telephone line and are used, for example, to monitor the tank contents in order to automatically send an order to refill the tank - or a corresponding indication of the need for refilling - to the energy supplier or to the tank user in good time.

The innovation is based on the task of improving a generic arrangement so that it can be put into operation at any location with minimal installation effort and therefore at a reasonable cost.

This object is achieved by an arrangement having the features of claim 1.

In other words, the innovation proposed by Mr. Dipl.-Ing. Peter Roth proposes to enable a wireless installation of the arrangement: Both the data transmission and the power supply of the entire arrangement are wireless. This power supply is independent of the public power grid thanks to an energy storage device, so that no power supply line needs to be laid to install the arrangement.

The proposed arrangement provides in particular for the energy storage to be automatically refilled by a device for converting natural forces

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into electrical energy. For example, a water wheel can be installed near a river - or a wind turbine in windy areas - which supplies the system with electrical energy via a generator. In the event of any outages, for example when the water level is low or there is no wind, the energy storage device is provided as a buffer, so that a continuous supply of electrical energy to the system is ensured.

A commercially available solar module can be used as a particularly advantageous device for converting natural forces into electrical energy. The construction and financial outlay is lower than for the manufacture and installation of a small wind or hydroelectric power plant, and the arrangement can also be operated without any problems regardless of nearby flowing water or in wind-protected locations, as long as regular sunlight is guaranteed there.

The arrangement uses appropriate sensors to monitor parameters that are relevant to the liquid gas tank: for example, a level indicator can be provided to trigger an automatic reorder when the level is sufficiently low or to suggest a corresponding reorder to the tank owner. Alternatively or additionally, monitoring of the internal tank pressure can be provided, for example as a constant leakage check.

Advantageously, additional sensors can be provided to monitor the safety of the liquid gas tank, for example by sensors to detect whether the dome cover of the tank is open or closed or whether the housing of the control unit is open or closed. These sensors can, for example, be designed in the form of inexpensive and commercially available door switches, which register the respective open or closed positions.

The data connection can be advantageously established using a GSM modem. Such GSM modems are commercially available and contain a telephone component for establishing the wireless communication connection in a best

existing mobile network, and they also contain the modem component for converting the data into signals that can be transmitted over this mobile network.

An accumulator can advantageously be provided as energy storage

hen, as it is commercially available under the name "solar battery". Such accumulators are usually deep discharge-proof and optimally matched to the special charging characteristics as specified by solar modules and the corresponding solar charge controllers.

Preferably, a database and a time base can be provided in the area of the control or assigned to the control so that the signals or messages issued by the control together with an indication of the respective

date and time can be saved in the database. Regardless of whether the signals or messages can be sent via the wireless data connection or not, all messages are saved so that the database can be used, for example, as part of

Service work can be read out. In particular, if regular test reports are planned, the arrangement can be reviewed if such test reports are not received, so that the database can then also be used to view those reports that have been given

if they could not be transmitted via the wireless data connection.

Preferably, a circuit for energy saving can be provided, the arrangement basically being

Energy saving mode is used. Only for sending a

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message, the controller can exit the energy saving mode and supply energy to all components required to send the message.

In order to enable simple monitoring of the current function of the arrangement, a display can preferably be provided which indicates that the arrangement is currently in energy saving mode. In order for this display to consume as little energy as possible, it can be designed, for example, in the form of a light signal which only flashes intermittently, whereby an LED can be provided as a particularly energy-saving lighting device.

The messages sent can be sent in the form of an SMS. This is a cost-effective and commercially available method of transmission and enables the messages to be output in plain text.

If a message could not be sent via the wireless data connection, an error circuit can preferably be activated so that if a message could not be sent properly, the message is sent again after a specified time period. This error circuit can, for example, provide that the message is attempted again after a specified time period. In the event of bottlenecks in the mobile network, this can ensure that the message is transmitted as far as possible - albeit with a time delay. It can be specified that a certain number of repetitions are attempted, whereby the time intervals between the transmission attempts can be designed differently or can depend on the charge level of the energy storage device.

Furthermore, this error circuit can activate a display if a message still could not be transmitted. For example, an LED can be provided that lights up continuously to indicate an error. In a particularly simple

Depending on the design of the arrangement, the same LED can be used for this purpose which can also be used to indicate the energy saving mode.

If, after several transfer attempts,

If the message could finally be transmitted, this error display can be switched off.

When the control leaves the energy saving mode to transmit a message, a voltage converter, a modem and a measuring transducer supply unit can be switched on. The modem automatically dials into the central computer in a reporting center and transmits the pending data volumes. Here, a further notification can be provided, for example also via a

Mobile network to a service technician, whereby the message sent to this service technician can preferably be sent as an SMS in plain text so that this technician can then respond to the message as quickly as possible. 20

For example, if the opening of the control cabinet door of the arrangement is reported or if a possible leak is indicated by the pressure in the supply line falling below the minimum, the notification can be accompanied by a special reference to the particular urgency of this message.

so that these reports can be responded to immediately.

The modem can usually be operated with 12 volts, whereby the energy storage is preferably designed as a 12 volt battery. The voltage converter mentioned above is used to transform the voltage from 12 to 24 volts in order to operate the measuring transducer power supply. This sends an intrinsically safe circuit to a measuring probe provided in the liquid gas tank. The signal returned from this probe is

then converted into a current flow by the transmitter supply unit.

carry, for example, a current flow of 4 to 20 mA, whereby this signal is in turn converted by the controller into a percentage value of the tank content, so that the fill level of the tank is determined.
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The control system can preferably switch the arrangement back to energy saving mode after sending the message. In this case, a predefined time window can be provided for this, so that, for example, the system switches back to energy saving mode after a fixed time of two minutes.

because it can be assumed that the report can usually be submitted within this time period.

However, a status message can also be evaluated,

for example, a status message from the GSM module, so that the corresponding switch back to energy saving mode can take place immediately after the message has been transmitted.

An embodiment of an arrangement according to the invention is explained in more detail below with reference to the drawings.

Fig.1 a schematic representation of a configuration

an arrangement according to the innovation, and Fig.2 a perspective view of an installed arrangement

In Fig.1, 1 denotes an arrangement which is used for

Monitoring a liquid gas tank. The arrangement 1 comprises a control 2. A solar module 3 is provided to supply energy to the control 2, for example a polycrystalline cell with a peak output of 20 watts, a voltage of 16 volts and a current of 1.25 amperes.

The surface of the solar module 3 is exposed to sunlight and the solar cell of the solar module 3 feeds a solar battery 4, which serves as a buffer and enables messages to be sent even at times of low radiation, especially in the dark. A solar charge controller 5 serves to limit the charging current and also protects the battery by switching off at low voltage. A visual voltage display can be provided by a multi-colored LED or several LEDs.

A voltage converter 6 is provided between the solar battery 4 and a measuring transducer supply unit 7 so that this measuring transducer supply unit can be operated with a voltage different from the battery voltage.

A measuring probe 8 is connected to the measuring transducer supply unit 7, which determines, for example, the fill level and/or internal pressure in the liquid gas tank. The signals from this measuring probe are fed to the control unit 2 via the measuring transducer supply unit 7, with other signal inputs also being provided on the control unit 2, so that, for example, the position of the control cabinet door is monitored, in which control cabinet the control unit 2 is located. The open or closed position of the dome cover of the liquid gas tank is also monitored by a separate signal input.

If there are such sensor signals that a message should be sent, the control 2 switches from an energy-saving mode to a transmission mode, whereby the opening of the dome cover, the opening of the control cabinet door or the undershoot of the minimum pressure within the liquid gas line serve to do this. In the case of such sensor signals, the control switches on the power supply to the voltage converter and the measuring transducer supply unit as well as to a GSM modem 9 so that this can then transmit the message via a mobile network.

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Fig. 2 shows an installation situation of the proposed arrangement: On a property, a liquid tank is arranged in the ground within a fence 10, with a dome 11 protruding from the ground and closed with a dome cover. A control cabinet 12 is also installed within the fence 10, which is designed as a standing desk and has a surface on its top for receiving the solar module 3.
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The arrangement shown is particularly advantageous in that it can be constructed inexpensively from commercially available individual elements.

Claims (14)

1. Arrangement for monitoring the contents of liquefied gas tanks,
with a sensor to determine a parameter relevant to the liquid gas tank - such as the tank content or the supply pressure,
and with an electronic control system that can be connected to a control center via a data connection,
wherein the controller is designed to emit a signal depending on the parameter,
characterized ,
that the data connection is wireless,
and that a device for converting natural forces into electrical energy - such as a solar module - and an energy storage device are provided to supply energy to the arrangement. 2. Arrangement according to claim 1, characterized by sensors for detecting the closed or opened state of the tank dome cover and 7 or the housing which contains the control and transmission components. 3. Arrangement according to claim 1 or 2, characterized by a GSM modem for establishing the data connection. 4. Arrangement according to one of the preceding claims, characterized in that an accumulator referred to as a "solar battery" with gel as electrolyte is provided as the energy storage device. 5. Arrangement according to one of the preceding claims, characterized by a database and a time base, wherein the signals or messages output by the controller are stored in the database together with the respective time information. 6. Arrangement according to one of the preceding claims, characterized by a circuit for energy saving,
whereby the control always switches the arrangement into energy saving mode,
and wherein the controller switches off the energy saving mode when a message is to be issued based on the sensor signals. 7. Arrangement according to one of the preceding claims, characterized by an indication that the arrangement is currently in energy saving mode. 8. Arrangement according to one of the preceding claims 7, characterized in that the display is designed as an LED which is controlled by a display circuit and lights up at intervals. 9. Arrangement according to one of the preceding claims, characterized in that the control outputs the message as an SMS (short message service). 10. Arrangement according to one of the preceding claims, characterized by an error circuit which activates a display if the transmission of a message has failed. 11. Arrangement according to claim 10, characterized in that the display is designed as an LED which is controlled by a display circuit and lights up continuously. 12. Arrangement according to claim 6, characterized in that the control switches on a voltage converter, a modem and a measuring transducer supply unit in order to issue a message. 13. Arrangement according to claim 12, characterized in that the control switches the arrangement back to the energy saving mode after a predetermined period of time. 14. Arrangement according to claim 12, characterized in that the control switches the arrangement back to the energy saving mode when the message has been transmitted.