EP3887727A1

EP3887727A1 - Heating installation and method for operating a heating installation

Info

Publication number: EP3887727A1
Application number: EP19813453.8A
Authority: EP
Inventors: Hendrik HOESSEL; Alexander Thomas LAUTERLEN
Original assignee: Simplex Armaturen und Systeme GmbH
Current assignee: Simplex Armaturen und Systeme GmbH
Priority date: 2018-11-28
Filing date: 2019-11-27
Publication date: 2021-10-06
Also published as: DE102018130189B4; WO2020109394A1; DE102018130189A1

Abstract

The invention relates to a heating installation (1) comprising a heating circuit distributor (4) with a distributor beam (5) and a collection beam (6), heating circuits (7; 8) connected to the heating circuit distributor (4), a control device (9), a feed line (10) which is connected to the distributor beam (5), a return line (11) which is connected to the collection beam (6), a feed temperature sensor (12) which is arranged in the feed line (10), a respective volumetric flow rate measuring device (13; 14) in each heating circuit (7; 8), and a respective remote-controlled actuator valve (15; 16) in each heating circuit (7; 8), wherein the feed temperature sensor (12), the volumetric flow rate measuring devices (13; 14), and the actuator valves (15; 16) are connected to the control device (9). Each volumetric flow rate measuring device (13; 14) of the heating circuits (7; 8) comprises a CTA sensor (17; 18) and is arranged in the region of the collection beam (6), and the heating installation (1) comprises a feed temperature sensor (22) arranged in the feed line (10), said feed temperature sensor (22) detecting the temperature of a medium (3) flowing through the feed line (10) and being connected to the control device (9).

Description

"Heating installation and method for operating a heating installation"

The invention relates to a heating installation and a

Procedure for operating a heating installation according to the

8.

A heating installation is known from DE 10 2015 119 801 A1, the heating installation comprising a heating circuit distributor with a distributor bar and a collector bar to which

Heating circuit distributor connected heating circuits, one

Control device, a flow line connected to the distributor bar, one connected to the collector bar

Return line, each includes a volume flow measuring device in each heating circuit and a remote-controlled control valve in each heating circuit, the

Volume flow measuring devices and the control valves to the

Control device are connected.

It is the object of the invention to propose a heating installation and a method for operating a heating installation which is designed such that both control and monitoring of an operation of the

Heating installation is easily possible.

This object is achieved on the basis of the features of the preamble of claim 1 and 8 by the characterizing features of the respective claim. Advantageous and expedient further developments are specified in the respective subclaims.

In the heating installation according to the invention, each volume flow measuring device of the heating circuits comprises a CTA sensor and each volume flow measuring device is in the range of

Collective bar arranged and includes the heating installation a flow temperature sensor arranged in the flow line, wherein the flow temperature sensor detects the temperature of a medium flowing through the flow line and sends it to the

Control device is connected. This is with the built-in components of the control device by means of a program which is based on the temperature of the

Flow line flowing medium and the temperature of the medium flowing past the CTA sensors of the heating circuits and the volume flows recorded by the CTA sensors of the heating circuits determined by the heating circuits, possible, by means of the control valves, an adjustment of the heating circuits pro

Time unit of heat output to set values so that an automatic hydraulic adjustment of the heating installation can be carried out. With such a

Heating installation, hydraulic adjustment can therefore be repeated and inexpensive. Energy flows from the heating circuits can be correspondingly

regulate automatically according to specifications.

Furthermore, it is provided that the flow temperature sensor is designed as a CTA sensor, which alternately one

Temperature of the medium and a flow velocity of the medium are recorded. As a result, the control device knows a volume flow which is fed to the heating circuit distributor, so that by opening one of the heating circuits by means of the

Control valve and closing all other heating circuits by means of the other control valves the volume flow in the

Flow line or the return line with a volume flow in the open heating circuit can be compared. This is an automatic leak detection and / or

Determination of a cross-section, which is a line section in which a measuring probe of the respective CTA sensor is arranged, for this purpose a cross-section of the supply line or the return line in the area of the measuring probe there CTA sensors is known. In order to be able to record a volume flow in the measuring mode, the line section in the flow direction is one with a length section that begins before the measuring probe and ends after the measuring probe

remain the same, deposited in the control device

Cross section formed. The same applies to the same

Volume flow with a large cross section of the line section, the flow rate lower than with a small cross section of the line section.

It is also provided for the heating installation

To form distribution bars as distribution lines and the

Form the collecting bar as a collecting line. In this way, the advantages of the invention can also be achieved with old pipework.

Accordingly, it is also envisaged that the

Distribution line and the manifold extend over at least two floors of a building. So the heating circuits can be arranged on several floors.

Furthermore, it is provided that radiators arranged in the heating circuits each have a bypass such that the medium can flow past the respective radiator.

This also enables a series connection of radiators in the individual heating circuits without a closed radiator in the heating circuit being able to impair the functioning of the heating circuit.

It is also contemplated that each CTA sensor will be one

Communication module comprises, wherein the communication modules are connected to each other and / or via the control device to form a communication network and in which

Communication network the data recorded by the CTA sensors be brought together. In particular, if you are trained as a radio network, the communication network enables

The most varied arrangement of the communication modules in a building makes it easy to combine the data.

Finally, it is provided to evaluate the acquired data in such a way that in the communication modules or in one of the communication modules or in the control device

Control commands for the motor-adjustable control valves are generated, the control commands being dimensioned in such a way that all heating circuits are hydraulically balanced in such a way that on average each heating circuit is supplied with a pre-programmed amount of energy. This makes it special

economical operation of the heating installation possible.

The inventive method for operating a

Heating installation according to at least one of the

Device claims provides that the means of

Flow temperature sensor measured temperature of the medium and the temperatures and measured using the CTA sensors

Flow rates of the medium flowing back from the heating circuits in the collecting bar are evaluated by the control device for controlling and / or monitoring the heating installation. The measured values of sensors designed and arranged in this way allow the

Control and monitor heating installation with a small number of sensors on a large scale.

It is envisaged that a repeated measurement of this

Temperatures and flow velocities occur and that from this the amount of heat emitted by the individual heating circuits per unit of time on the basis of cross sections of

Line sections, in which measuring probes of the CTA sensors are included, is calculated. On the basis of such data the operation of the heating installation can be easily monitored and the amount of heat given off by the heating circuits can be calculated or logged.

It is also provided that

- That the control valves of those heating circuits, the amount of heat emitted is above a target value, from the

Control device to be closed further,

- That the control valves of those heating circuits whose heat output is below a target value from

Control device can be opened further and

- That this process is repeated until the heat quantities emitted by the heating circuits per unit of time correspond to the target values. With this procedure, hydraulic balancing can be carried out automatically on the heating installation. This is particularly important for commissioning a newly created heating installation or for a

Recommissioning of a heating installation modified, for example, by new radiators, is advantageous, since this saves a considerable amount of work compared to a hydraulic adjustment carried out manually.

It is also intended

that the temperature of the medium is determined in a first sequence by applying a low heating power to a platinum measuring resistor of one of the CTA sensors,

- That in a second sequence the flow rate of the medium is determined by this CTA sensor, for which purpose a certain heating power is applied to the platinum measuring resistor of this CTA sensor, thereby generating heat at the platinum measuring resistor and this heat from the flowing one Medium is removed and a time-dependent temperature change of the medium is determined and

- that then from the determined flow velocity and a volume flow of the medium is calculated on the basis of a cross section of a line section in which a measuring probe of this CTA sensor is accommodated,

- A composition of the medium is then determined on the basis of a measurement of a settling time for a temperature increase of the medium caused by a heating by means of the CTA sensor when the medium is at rest, and a thermal conductivity of the medium or a heat capacity of the medium is determined from this becomes.

This makes it possible to automatically check whether the heating installation is filled with the correct medium, with the correct medium being used under the term "correct medium"

Media composition when using mixtures is to be understood.

It is planned:

- That the control valve of one of the heating circuits is opened and that the control valves of all other heating circuits

getting closed,

that the volume flow of the medium is measured by means of a CTA sensor arranged in the flow line on the basis of a known cross-section, which the flow line has in the area of a measuring probe of this CTA sensor,

- That at the same time as the CTA sensor of the open

Heating circuit is measured,

- Measured values recorded at the same time in the control device of the CTA sensor arranged in the flow line and of the CTA sensor arranged in the open heating circuit are assigned to one another and

- That in the control device from the deviations of the measured values of the CTA sensor arranged in the heating circuit compared to the CTA sensor arranged in the flow line, a cross section of the pipe section of the open

Heating circuit is calculated. This can result in a new Heating installation can be checked automatically if the data is stored accordingly, whether the CTA sensors are in

Line sections are arranged with the intended cross section.

It is also provided that

- That the procedure for determining a

Media composition is repeated time-controlled and / or event-controlled and

- That the values for thermal capacity and / or thermal conductivity determined in the individual measurements with one another

be compared and

- that deviations which suggest a change in the medium are reported by the control device. This makes it possible to check at intervals whether the correct medium is still being used and in particular to determine whether the medium is contaminated or has decomposed. A time-controlled repetition of the process is, for example, when the process e.g. daily or weekly or monthly at a specific time

is carried out. An event-controlled repetition of the process occurs, for example, if the process e.g. is carried out as part of maintenance of the heating installation.

It is also intended

- That the procedure for identifying the connected pipe cross-section is repeated time-controlled and / or event-controlled and

- that the values for the volume flow determined in the individual measurements are compared with one another and

- that deviations from previous measurements, which were carried out under the same system conditions and in particular with the same valve positions and which were based on a Change the cross section of the pipe section of the open heating circuit, from which close

Control device to be reported. Accordingly, the heating installation can be automatically checked at intervals to determine whether the cross sections of the line sections in which the measuring probes CTA sensors of the heating circuits are located

are arranged, e.g. narrow through deposits. As a result, sections of the

Detect heating installation in a targeted manner.

Furthermore, it is provided that at least two of the in the

Claims 9 to 14 described procedures repeated

to be carried out sequentially or in parallel. In this way, a heating installation can be automatically comprehensively monitored.

Finally, it is intended

- That the volume flow measuring devices with their CTA sensors alternate a flow rate and a

Measure the temperature of the medium flowing through the respective heating circuit,

- That the flow temperature sensor designed as a CTA sensor, alternately a volume flow and a temperature of the

Measure the distribution bar of the incoming medium,

- That the CTA sensors are controlled by the control device such that the CTA sensors arranged in the heating circuits always measure the temperature of the medium when the CTA sensor arranged in the feed line detects the

Flow rate measures and

- That the CTA sensors are controlled by the control device in such a way that the CTA sensors arranged in the heating circuits always measure the flow velocity when the CTA sensor arranged in the supply line detects the

Measures the temperature of the medium. Through such a coordinated operation of the arranged in the heating circuits CTA sensors and the CTA sensor assigned to the flow line, it is possible to increase the accuracy of the value calculated on the basis of the measured flow velocities for the volume flow, since the total volume flow either based on the flow velocity measurements of the

Flow line assigned to the CTA sensor is determined or is determined on the basis of the flow velocity measurements of the CTA sensors arranged in the heating circuits, and thus there is virtually no interruption of the volume detection by temperature measurements.

In the sense of the invention, a heating installation is also understood to mean an installation by means of which e.g. it is possible to lower the temperature in a building.

For the purposes of the invention, a CTA sensor is used

Flow sensor understood, which is operated according to the principle of "constant temperature anemometry" and for this purpose comprises a measuring probe which is guided into a medium

Measuring probe is controlled sequentially, i.e. in a sequence the media temperature is set by applying a low

Heating power is determined on the platinum measuring resistor and in a further sequence a certain heating power is applied on the platinum measuring resistor. The resulting heat on

Measuring resistance is removed from the prevailing media flow and thus provides information about the

Flow velocity. The flow rate will

- either by applying a defined heating output and by measuring the change in resistance between

Temperature determination phase and heating phase determined

- or by applying a regulated excess temperature to the sensor (e.g. 10 K above the media temperature) and by measuring the heating power that is required around this

To reach excess temperature, determined. The volume flow can then be calculated from the flow velocity and the known geometric shape of the sensor housing. The CTA sensor determines the temperature and

Flow sequentially. For a permanent measurement of

Temperature and flow come in two CTA sensors

Series connection for use. It is also intended to calculate the heat flow or energy consumption from the measured values.

In the sense of the invention, an amount of heat is always understood to be a quantity of heat measured or emitted per unit of time. Heat quantities specified per unit of time are in the sense of

Invention also referred to as energy flow.

Further details of the invention are described in the drawing using schematically illustrated exemplary embodiments.

Here shows:

Figure 1: a schematic representation of a

Heating installation according to the invention.

In Figure 1 is a schematic representation

Heater installation 1 shown. This comprises a heater 2 for heating a medium 3, which is used for heat transfer. Furthermore, the heating installation 1 includes one

Heating circuit distributor 4. This comprises a distributor bar 5 and a collecting bar 6. There is one on the heating circuit distributor 4

A large number of heating circuits are connected, a first heating circuit 7 and a second heating circuit 8 being shown by way of example. In addition, the heating installation 1 comprises a control device 9, one on the distributor bar 5

connected flow line 10, which this with the heater 2 connects, one connected to the collecting bar 6

Return line 11, which connects it to the heater 2. A flow temperature sensor 12 is located in the flow line 10

arranged. Furthermore, the heating installation in each of the heating circuits 7, 8 comprises a volume flow measuring device 13, 14 and in each of the heating circuits 7, 8 a remote control

Control valve 15, 16. Here, the flow temperature sensor 12, the volume flow measuring devices 13, 14 and the control valves 15,

16 connected to the control device 9. Each

Volume flow measuring device 13, 14 of the heating circuits 7, 8 is arranged on the collecting bar 6 and thus in the area of the collecting bar and comprises a CTA sensor 17, 18. In the

Heating circuits 7, 8 are each shown as examples

Radiators 20, 21 arranged, which also in the form of

Heating loops as floor and / or wall and / or

Ceiling heating can be formed. Connections V2, V12,

V15-V18 of the heater 2, the flow temperature sensor 12, the

Control valves 15, 16 and the CTA sensors 17, 18 with the

Control device 9 are shown by dashed lines. These connections can either be wired or wireless. According to one embodiment variant, the flow temperature sensor 12 is also a CTA sensor 22

educated. All CTA sensors 17, 18, 22 comprise one

Measuring probe 17a, 18a, 22a, each in one

Pipe section 17b, 18b, 22b protrudes and the medium 3 flows around. The pipe sections 17b, 18b, 22b each have a cross section Q17b, Q18b, Q22b in the area of the measuring probes 17a, 18a, 22a. The heating circuits 7 and 8 can be opened and closed step by step by means of the control valves 15, 16.

The control valves 15, 16 receive corresponding control commands via the connections V15 or V16 from the control device 9.

With dashed lines is around the radiator 20 of the first

Heating circuit 7 indicated a room R, which by the first Heating circuit 7 is heated. There is a in this room

Temperature sensor RST arranged, which detects an actual temperature of the room air and wirelessly forwards it to the control device 9. A target temperature for the room R is stored in the control device 9. Accordingly, the amount of heat supplied to the first heating circuit 7 is increased by the

Control device 9 adapted to a heating target for room R by means of control commands for control valve 15.

If a composition of the medium is to be determined, one of the CTA sensors 17, 18 with the closed

Control valve 15 or 16 and thus stationary medium M a

Settling time for heating the CTA sensor 17,

18 caused increase in temperature of the medium M and a composition of the medium is determined from this in the control device in comparison with stored reference values.

In order to be able to record a volume flow in the measuring mode, the line section in which the measuring probe of the CTA sensor is arranged is designed in the flow direction over a length section beginning before the measuring probe and ending after the measuring probe with a constant cross section stored in the control device, so that there is a kind of measuring orifice in the area of the CTA sensor, whose geometry in the

Control device for calculating the volume flow from the measured values for the flow velocity is stored.

It is also provided by means of the control device 9 a coordinated operation of the CTA sensors 16, 17 arranged in the heating circuits 7, 8 and of the CTA sensor 22 assigned to the flow line 10 in order to ensure the accuracy of the volume flow on the basis of the measured flow velocities calculated value to increase. For this, the Total volume flow based on the

Flow velocity measurements of the CTA sensor 22 assigned to the flow line 10 are determined as long as those in FIGS

Heating circuits 7, 8 arranged CTA sensors 16, 17 die

Measure the temperature of the medium 3. Furthermore, the

Total volume flow based on the

Flow velocity measurements in the heating circuits 7,

8 arranged CTA sensors 16, 17 determined as long as the

Flow line 10 assigned CTA sensor 22 measures the temperature of the medium 3. Through this alternating operation of the CTA sensors 16, 17, 22, the volume flow can be recorded not only with interruptions, but continuously. It is provided that a time period for which the CTA sensors 16, 17 assigned to the heating circuits 7, 8 measure the flow rate corresponds to a time period for which the

Flow line 10 associated CTA sensor 22 die

Measures flow velocity. A value between 5 seconds and 50 seconds and in particular a value between 5 seconds and 15 seconds is provided for the time period, the value for the time period being particularly preferably approximately 10 seconds.

Reference symbol list:

1 heating installation

2 heating

3 medium

4 heating circuit distributors

5 distributor bars

6 collective bars

7 first heating circuit

8 second heating circuit

9 control device

10 supply line

11 return line

12 flow temperature sensor

13 volume flow measuring device

14 volume flow measuring device

15 control valve

16 control valve

17 CTA sensor

17a measuring probe

17b pipe section

18 CTA sensor

18a measuring probe

18b pipe section

20 radiators in 4

21 radiators in 5

22 CTA sensor as 12

22a measuring probe

22b pipe section

Q17b cross section of 17

Q18b cross section of 18

Q22b cross section of 22

R space RST temperature sensor in room R

V2 connection between 2 and 9 V12 connection between 12 and 9 VI5 connection between 15 and 9 VI 6 connection between 16 and 9 VI7 connection between 17 and 9

VI8 connection between 18 and 9

Claims

Expectations :

1. Heating installation (1) comprehensive

- a heating circuit distributor (4) with a distributor bar (5) and a collecting bar (6),

- Heating circuits connected to the heating circuit distributor (4)

(7; 8),

- a control device (9),

- One connected to the distributor bar (5)

Flow line (10),

- A return line connected to the collecting bar (6)

(11),

- A volume flow measuring device (13; 14) in each heating circuit (7; 8),

- Each have a remote-controlled control valve (15; 16) in each heating circuit (7; 8) and

- The volume flow measuring devices (13; 14) and the control valves (15; 16) are connected to the control device (9),

characterized,

- That each volume flow measuring device (13; 14)

Heating circuits (7; 8) comprises a CTA sensor (17; 18) and is arranged in the region of the collecting bar (6) and

- That the heating installation (1) one in the

Flow line (10) arranged flow temperature sensor (12),

- The flow temperature sensor (12) detects the temperature of a medium (3) flowing through the flow line (10) and is connected to the control device (9).

2. Heating installation according to claim 1, characterized in that the flow temperature sensor (12) as a CTA sensor (22) is formed, which alternately detects a temperature of the medium (3) and a flow velocity of the medium (3).

3. Heating installation according to claim 1 or 2, characterized

characterized in that the distributor bar is designed as a distributor line and that the manifold is designed as a manifold.

4. Heating installation according to claim 3, characterized in that the distribution line and the manifold over

extend at least two floors of a building.

5. Heating installation according to at least one of the

preceding claims, characterized in that arranged in the heating circuits radiators each have a bypass

have such that the medium (3) on the respective

Radiators can flow past.

6. Heating installation according to one of the preceding claims, characterized in that each CTA sensor

Communication network, the data recorded by the CTA sensors are merged.

7. Heating installation according to claim 6, characterized in that the recorded data are evaluated such that control commands for the motor-adjustable control valves are generated in the communication modules or in one of the communication modules or in the control device, the

Control commands are dimensioned such that a hydraulic

All heating circuits are adjusted in such a way that on average each heating circuit is supplied with a pre-programmed amount of energy.

8. Procedure for operating a heating installation (1)

according to at least one of claims 1 to 7, characterized in that the temperature of the medium (3) measured by means of the flow temperature sensor (12) and the temperatures and measured by means of the CTA sensors (17; 18)

Flow velocities of the medium (3) flowing back from the heating circuits (7; 8) into the collecting bar (6)

Control device (9) for controlling and / or monitoring the heating installation (1) can be evaluated.

9. The method according to claim 8, characterized in that a repeated measurement of these temperatures and

Flow velocities take place and that from this that from the individual heating circuits (7; 8) per unit time

Amount of heat based on cross sections (Q17b; Q18b) of

Line sections in which measuring probes (17a; 18a) of the CTA sensors (17; 18) are accommodated are calculated.

10. The method according to claim 9, characterized in

- That the control valves (15; 16) of those heating circuits (7;

8), the amount of heat emitted is above a target value, are further closed by the control device (9),

- That the control valves (15; 16) of those heating circuits (7;

8), the amount of heat emitted is below a target value, are opened further by the control device (9) and

- That this sequence is repeated until the heating circuits (7; 8) emit per unit of time

Amounts of heat correspond to the target values.

11. A method for operating a heating installation (1) according to claim 8 comprising the steps: the temperature of the medium (3) is determined in a first sequence by applying a low heating power to a platinum measuring resistor of one of the CTA sensors (7; 8),

- Wherein in a second sequence the flow rate of the medium (3) is determined by this CTA sensor (7; 8), for which purpose a certain heating power to one

Platinum measuring resistor of this CTA sensor (7; 8) is applied, thereby generating heat at the platinum measuring resistor and this heat from the flowing medium (3)

is removed and a time-dependent temperature change of the medium (3) is determined and

- Then one from the determined flow velocity and on the basis of a cross section Q17b, Q18b

Line section in which a measuring probe (17a; 18a) of this CTA sensor (17; 18) is received

Volume flow of the medium (3) is calculated,

- Then, on the basis of a measurement of a settling time carried out by the CTA sensor when the medium is at rest, for a temperature increase of the medium caused by heating from stored reference values

Composition of the medium is determined and from this a thermal conductivity of the medium (3) or a thermal capacity of the medium (3) is determined.

12. A method for operating a heating installation (1) according to claim 8, comprising the steps:

- The control valve (15; 16) of one of the heating circuits (7;

8) opened and the control valves of all other heating circuits (8; 7) are closed,

- It is the volume flow of the medium (3) by means of a

the flow line (10) arranged CTA sensor (22) is measured on the basis of a known cross section (Q22b) which the flow line (10) has in the area of a measuring probe (22a) of this CTA sensor (22), - At the same time the open heating circuit (7; 8) is measured with the CTA sensor (17; 18),

- In the control device (9) are the same

Measured values of the CTA sensor (22) arranged in the flow line (10) and that in the

open heating circuit (7; 8) arranged CTA sensor (17; 18) assigned to each other,

- In the control device (9) from the deviations of the measured values of the CTA sensor (7; 8) arranged in the heating circuit (7; 8) compared to the CTA sensor (22) arranged in the flow line (10), a cross section (Q17b ; Q18b) of the pipe section (17b; 18b) of the opened

Heating circuit (7; 8) calculated.

13. The method according to claim 11, characterized in

- That the method according to claim 11 is repeated time-controlled and / or event-controlled and

- that the values determined for the individual measurements for thermal capacity and / or thermal conductivity are compared with one another and

- that deviations from previous measurements,

which was carried out under the same system conditions and in particular with the same valve positions and which indicate a change in the medium (3) are reported by the control device (9).

14. The method according to claim 12, characterized in that

- That the method according to claim 12 is repeated time-controlled and / or event-controlled and

- that deviations, which indicate a change in the

Cross section (Q17b; Q18b) of the pipeline section (17b; 18b) Have the opened heating circuit (7; 8) close, be reported by the control device (9).

15. Procedure for operating a heating installation according to

Claim 8, characterized in that at least two of the methods described in claims 9 to 14 are repeated

be carried out sequentially or in parallel.

16. A method for operating a heating installation (1) according to claim 8, wherein the operation is carried out in such a way

- The volume flow measuring devices (13; 14) with their CTA sensors (17; 18) alternately measure a flow rate and a temperature of the medium (3) flowing through the respective heating circuit (7; 8),

that the trained as a CTA sensor (22)

Flow temperature sensor (12), alternately measure a volume flow and a temperature of the medium (3) flowing to the distributor bar (5),

- That the CTA sensors (17; 18; 22) from the

Control device (9) are controlled such that the CTA sensors (17; 18) arranged in the heating circuits (7; 8) always measure the temperature of the medium (3) when the temperature in the

Flow line (10) arranged CTA sensor (22)

Flow rate measures and

- That the CTA sensors (17; 18; 22) from the

Control device (9) are controlled in such a way that the CTA sensors (17; 18) arranged in the heating circuits (7; 8) always measure the flow rate when the flow rate in the

Flow line (10) arranged CTA sensor (22) measures the temperature of the medium (3).