CZ2007789A3 - Circuit arrangement for checking accuracy of flow meters in hot water central distribution system - Google Patents

Abstract

The wiring is formed by an internal circulation loop (10) equipped with an input line (2) with an input flow meter (1), an output line (3) with an output flow meter (5) and at least one outlet (11, 12, 13, 14, 15) to one outlet (111, 112, 113, 114, 115) for hot water extraction. An inlet shut-off valve (81) is arranged between the inlet flow meter (1) and the water flow direction of the first outlet (11) of the first outlet (111). An outlet shut-off valve (82) is arranged in the water flow direction between the last outlet (15) of the last outlet (115) and the outlet flow meter (5). To check the accuracy of the inlet flow meter (1) and the outlet flow meter (5), the inlet line (2) between the inlet flow meter (1) and the inlet shutoff valve (81) is connected to the outlet line (3) between the outlet shut-off valve (82) and the outlet flow meter. (5) using a control line (9) with a check shut-off valve (83). In accordance with the invention, a bypass line (7) is connected in parallel to the inlet shut-off valve (81), resulting in its inlet line (2) in the direction of hot water flow upstream of the inlet flow meter (1) or into the outlet line (3) in the direction of hot water flow downstream of output flow meter (5). The bypass line (7) results in a hot water flow line between the inlet shut-off valve (81) and the shut-off valve (82). A flow meter (61, 64) is disposed in the bypass line (7) and / or between all the debris (11, 12, 13, 14, 15) and outlets (111, 112, 113, 114, 115).

Description

(57)

The circuit consists of an internal circulation loop (10) provided with an inlet conduit (2) with an inlet flowmeter (1). an outlet conduit (3) with an outlet flow meter (5) and at least one branch (11.12,13, 14, 15) to one outlet (11, 11, 112, 113, 114, 115) for hot water abstraction. An inlet shut-off valve (81) is arranged between the inlet flow meter (1) and the downstream of the first outlet (111) in the direction of water flow. A flow shutoff valve (82) is provided between the last tap (15) of the last outlet (115) and the outlet flowmeter (5). To check the accuracy of the inlet flowmeter (1) and the outlet flowmeter (5), the inlet line (2) between the inlet flowmeter (I) and the inlet shut-off valve (81) is connected to the outlet line (3) between the outlet shut-off valve (82) and the outlet flowmeter (5) by means of a control line (9) with a check shut-off valve (83). According to the invention, a bypass line (7) is connected in parallel to the inlet shut-off valve (81) and flows into the inlet line (2) upstream of the inlet flowmeter (1) or the outlet line (3) downstream. output flowmeter (5). The bypass line (7) terminates in a line in the direction of the hot water flow between the inlet shut-off valve (81) and the outlet shut-off valve (82). A flow meter (61, 64) is disposed in the bypass line (7) and / or between all branches (II. 12, 13, 14, 15) and the outlets (111, 112, 113, 114, 115).

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Wiring for checking the accuracy of flow meters in the central hot water distribution

Technical field

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a circuit for checking the accuracy of flow meters in a central hot water distribution system comprising an internal circulation loop provided with an inlet line with an inlet flow meter, an outlet line with an outlet flow meter and at least one branch to one hot water outlet. The first shut-off of the first outlet has an inlet shut-off valve and an outlet shut-off valve is provided in the direction of water flow between the last outlet of the last outlet and the outlet flowmeter and the inlet duct between the inlet flowmeter and the inlet shut-off valve is connected to the outlet the line between the outlet shut-off valve and the outlet flow meter by means of a control line with a check shut-off valve.

BACKGROUND OF THE INVENTION

A common requirement for flow meters of central hot water systems is the reliability and accuracy of hot water consumption measurement. It is known from the prior art to connect a central distribution system according to which an inlet shut-off valve is arranged between the inlet flow meter and the water outlet direction of the first outlet of the first outlet and an outlet shut-off valve is arranged in the water flow direction between the last outlet of the last outlet. and the supply line between the inlet flow meter and the inlet shut-off valve is connected to the outlet line between the outlet shut-off valve and the outlet flow meter by means of a control line provided with a check shut-off valve. In the control phase of the central hot water system, the inlet shut-off valve and outlet shut-off valve are closed and the check shut-off valve is open. The hot water from the external distribution system is not supplied to the distribution loop, but is returned from the supply line via the control line to the external distribution system via the control line. In doing so, the measurement accuracy of the inlet and outlet flow meters is checked, for example by comparing or correcting the flow values measured with the inlet flow meter and the outlet flow meter to reduce the measurement error and eliminate illogically measured values and measurement errors. The input and output flow meters are usually set to a defined error. The measuring accuracy of the inlet and outlet flow meters can be checked only in such a time when there is no hot water consumption, because by closing the inlet and outlet valves the distribution loop is disconnected from the hot water supply from the external distribution. It is desirable to provide a circuit for checking the accuracy of the flow meters in the central hot water distribution that would allow water to be withdrawn during the accuracy check of the inlet and outlet flow meters. Enabling water abstraction during the accuracy check of the inlet and outlet flow meters is also required by the valid technical conditions for hot water supply. It is necessary to avoid the situation when the customer opens the water tap and after finding that the water from the tap does not leak, leave the water tap open. After the water supply has been restored, the water leaking from the non-closed water tap can cause serious damage. From patent ·· ♦ · ♦ ·. · «>> '' '' '' · · · · · · · ·

3 of the Applicant's PV 2005-486 it is known to connect a central hot water distribution system of said genus, in which a bypass line is connected in parallel to the inlet shut-off valve connected by its inlet to the supply line upstream of the inlet shut-off valve and its outlet into the line a flow indicator or flow meter is arranged in the direction of the hot water flow between the inlet shut-off valve and the first branch of the first outlet and in the bypass line. The connection of the central hot water distribution according to PV 2005-486 allows the hot water to be drawn during the accuracy check of the input and output flowmeter, but the result of the check is distorted by the hot water take-off during the check. in the bypass line, it is necessary to include the measured values of the inlet and outlet flow meters. The error of the flowmeter in the bypass line is thus reflected in the result of checking the accuracy of the input and output flowmeter. It is an object of the present invention to satisfy the current technical conditions for hot water supply and to ensure that hot water can be drawn during the accuracy check of the flow meter and at the same time to achieve high accuracy and reliability of the check. .

SUMMARY OF THE INVENTION

Disadvantages of the prior art are eliminated and the object of the invention is fulfilled by the connection for checking the accuracy of the flowmeter in the central hot water distribution system formed by an internal circulation loop provided with an inlet duct with an inlet flowmeter.

an outlet line with an outlet flowmeter and at least one branch to one hot water outlet, wherein an inlet shut-off valve is provided between the inlet flowmeter and the first outlet of the first outlet and downstream of the last outlet of the last outlet and the outlet flowmeter the outlet shut-off valve (82) and, to check the accuracy of the inlet and outlet flow meters, the inlet duct between the inlet and outlet shut-off valves is connected to the outlet duct between the outlet shut-off valve and outlet flowmeter by a control line with a check shut-off valve in that a bypass line is connected in parallel to the inlet shut-off valve, which flows through its inlet into the inlet line in the direction of hot water flow in front of the inlet flow meter or into the outlet The line is downstream of the outlet flow meter and its outlet to the line in the direction of the hot water flow between the inlet shut-off valve and the outlet shut-off valve, with a flow meter located in the bypass line and / or between all branches and outlets. The main advantage of the wiring for checking the accuracy of flow meters according to the invention is the fact that any hot water consumption does not affect the accuracy of the measurement of the inlet and outlet flow meters, since hot water is taken off the wiring. The amount of water flowing between the flow meters to be checked does not change. In addition to this advantage, the flow meter accuracy control circuitry of the invention retains all the advantages of the cited patent application PV 2005-486, i.e. the ability to control both the flow meter and flow meter, and the ability to remotely monitor flow meter accuracy.

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BRIEF DESCRIPTION OF THE DRAWINGS

The circuitry for checking the accuracy of the flow meters in the central hot water distribution system of the invention is shown in the drawings, in which Fig. 1 shows a circuit diagram with a flow sensor in the bypass line and Fig. 2 a circuit diagram with a flow meter in the bypass line.

Examples

According to FIG. 1, the central hot water distribution system consists of a circulation loop 10 provided with a supply line 2 with an inlet flow meter 1, an outlet line 3 with an outlet flow meter 5 and at least one branch 11, 12, 13, 14, 15 to at least one outlet 111, 112 , 113, 114, 115 for hot water. An inlet shut-off valve 81 is provided between the inlet flowmeter 1 and the first tap 11 of the first outlet 111 in the water flow direction, and an outlet shut-off valve 82 is provided in the water flow direction between the last tap 15 of the last outlet 115 and the outlet flow meter 5. 1 and the output flowmeters 5, the supply line 2 between the inlet flowmeter 1 and the inlet shut-off valve 81 is connected by a control line 9 to the control shut-off valve 83 with the outlet line 3 between the outlet shut-off valve 82 and the outlet flowmeter 5. The conduit 7 terminates by its inlet to the outlet conduit 3 in the direction of hot water flow downstream of the outlet flow meter 5 and its outlet to the conduit in the direction of the hot water flow between the inlet shut-off valve 81 and the outlet shut-off valve 82.

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The bypass line 7 connected in accordance with the invention allows water to be supplied to the object when the fittings 81, 82, 83 are switched so that the same amount of water flows through both flow meters 1 and 5. To measure the amount of hot water withdrawn from the outlets 111, 112, 113, 114, 115 during the accuracy measurement of the inlet flow meter 1 and the outlet flow meter 5, a flow meter 61 is provided in the bypass line 7. The shut-off valves 81, 82, 83 flow direction and multi-way valves or non-return valves can be used. The flow meter 61 arranged in the bypass line 7 may be connected to the evaluation unit 20 for evaluating the hot water consumption measurement during the accuracy check of the inlet flow meter 1 and the outlet flow meter 5. FIG. 2 shows the same wiring as in FIG. bypass line 7, which, according to FIG. 2, flows into the inlet line 2 in the direction of hot water flow upstream of the inlet flow meter 1. The check is carried out by switching the medium flow through the shut-off valve 83 and allowing the medium to flow through the line 9 standard), the function of the whole set of gauges is checked and the operation of measurement in defined parameters is enabled. At the same time, the possibility of water withdrawal from a separate part of the circulation loop at the time of inspection is also ensured. Additional fittings or non-return valves can be mounted on the bypass line 7. A pressure sensor can also be used to signal the function. The flow meters used to measure the flow and consumption of hot water in the circulation loop can also be used to measure the heat contained in the flowing medium. The comparison of the flowmeter with the control flowmeter can be performed by a separate device or this function can be provided by the evaluation unit of the meters used. The time and method of switching valves for inspection are not technically

- 7 limited. The frequency of controls and the way the measured values are processed and stored are not technically limited. The final further processing of the measured values and their display is also not technically limited.

Claims (1)

PROTECTION REQUIREMENTS Wiring for checking the accuracy of flow meters in a central hot water distribution system comprising an internal circulation loop (10) provided with an inlet line (2) with an inlet flowmeter (1), an outlet line (3) with an outlet flowmeter (5) and at least one branch (11) , 12, 13, 14, 15) to a single hot water outlet (111, 112, 113, 114, 115), wherein between the inlet flow meter (1) and the downstream of the first outlet (11) of the first outlet (111) an inlet shut-off valve (81) is provided, and an outlet shut-off valve (82) is provided in the direction of water flow between the last tap (15) of the last outlet (115) and the outlet flowmeter (5) and to check the accuracy of the inlet flowmeter (1) and outlet flowmeter (5) the inlet line (2) between the inlet flow meter (1) and the inlet shut-off valve (81) is connected to the outlet line (3) between the outlet shut-off valve (82) and the outlet flow meter (5) by means of a control line (9) with a control shut-off valve (83), characterized in that a bypass line (7) is connected in parallel to the inlet shut-off valve (81) and flows into the inlet line (2) upstream of the inlet flow meter (1) or outlet line (3) downstream of outlet flow meter (5) and its outlet in line downstream of hot water flow between the inlet shut-off valve (81) and the outlet shut-off valve (82), a line (7) and / or between all branches (11, 12, 13, 14, 15) and outlets (111, 112, 113, 114, 115) is provided with a flow meter (61, 64).