DE2444058A1 - INSTALLATION IN A WEATHER-DEPENDENT FLOW TEMPERATURE CONTROLLER OF A HEATING SYSTEM TO FACILITATE THE ADAPTATION OF CONTROLLER CHARACTERISTICS TO HEATING CURVES - Google Patents

Description

DIPL.-ING. HORST RÖ3E DIPL-JNG. PETBV. KOB

3353 Bad Gandersheim, September 13, 1974 P.O. Box 129 Hohenhöfen S Telephone: (05382) 2842 Telegram address: Siedpatent Badgandersheim

Our file no. 18/387

Aktiengesellschaft Adolph Saurer
Patent application dated September 13, 1974

Stock s ells ehaft
Adolph. Bricklayer

GH.9520 A rb ο η
Switzerland

Installation in a weather-dependent flow temperature controller a heating system to facilitate the adaptation of Resler characteristic curves to heating curves

The idea concerns one facility in one Weather-dependent flow temperature controller of a heating system to facilitate the adaptation of the controller characteristics of the flow temperature controller ^ to given heating curves with at least two adjustment links.

The heating curves depend on the heating system, the design of the building and the climate zone in which the building is located. Recorded in the coordinate system, the heating curves intersect at one point. At this point, the outside temperature is the same as the setpoint temperature of the room and consequently also the associated flow temperature Areas distant from this area are flat _o These areas distant from the point mentioned are the temperatures at which heating takes place _o For this reason, the heating curve is generally approximated by a straight line and treated accordingly (heating line). These straight lines

Bank account: Norddeutsche Landesbank, Bad Gandersheim branch, account no. 22,118,970 · Postscheckkonto · Hannover 66715 "" "'

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intersect at a point which does not coincide with the aforementioned intersection of the curves.

Known heating controllers generally have at least
two adjusting elements, by means of which the characteristic curves
the controller in the best possible agreement with the heating
be brought straight »On the one hand, the slope of the characteristic curve, also known as the" steepness ", can be influenced
and on the other hand a parallel shift of the characteristic
producible. j

Me decision by means of which of the adjustment members;

make the correct adjustment of the controller characteristic j

is difficult for an education specialist and often leads ■■

to incorrect settings:

The invention is based on the object under loading ^!

OTING the disadvantages of the known input devices ■ a device of the initially stated kind

to create, with the help of which the decision on the: choice of adjusting elements for the correct adjustment on

simple way taken and under simple operation;

can be made in the facility, with errors: both in the detection and in the setting as far as possible- '

should be avoided on the move «i

This object is achieved according to the invention in that | that one formed in a modified bridge circuit

electrical variable, which is used as a decision variable for an I.

optimal for the respective climatic area, for choice I. of the setting element to be actuated is equivalent to the decisive outside temperature, for the identification of the to

actuating adjusting member is used «, Here j

marking either by means of a simple optical display I.

or by mechanically blocking one of the two i

Adjusting members or by alternately coupling the j

more expedient adjustment member with a single loading '<

activity link, which is an additional benefit! extremely simple operation results and errors practical,

be excluded ,, j

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Further advantageous features and advantageous effects of the invention emerge from the patent claims and from the following explanation of exemplary embodiments of the invention.

Fig. 1 is a diagram in which the heating curves and associated control characteristics of two heating systems A and B. are shown

Pig. 2 a diagram in which two heating curves c and d are shown with the same design point and target value which are curved differently due to the different characteristic values of the radiators,

3 shows a diagram in which possible incorrect positions of the controller characteristic are drawn in,

Pig »4 an embodiment of a conventional circuit,

5 shows a circuit modified according to the invention starting from the Pig »4

Pig. ξ> and 7 another modified circuit starting from the Pig. 4th

In Pig. 1 are heat curves a and b and ^{f is} the corresponding control characteristic curves a and b ¹ of two different heating-indicated The heating curve a of a heating system A for a warmer climate is assigned, which requires a regulating characteristic curve a ^1, according to which an outside temperature of - 8 ° C never is fallen below (corresponds to "climate zone - 8 °"), whereas the heating curve b of a heating system B is assigned to a "climate zone - 20 °", which requires a controller characteristic curve b ¹ , and according to which an outside temperature of - 20 ° C is never fallen below » It should be noted that these curves only show the ratio of outside temperature / flow temperature, but do not include the flow rate of the heating medium and thus the total amount of heat transferred.

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temperature "fcgy _{max of} a heating system is given above all by the relative dimensioning of the heating surface per heated room volume.

These heating curves intersect at point Stt _K , at which the outside temperature reaches the setpoint of the room temperature and consequently also corresponds to the associated flow temperature

In Fig. 1 the heating limit C is further demonstrated, that is that high ambient temperature must be heated in the _e case of higher external temperatures is a heating no longer necessary "usually Accordingly it is apparent that the range of the heating curve (a, b ), which is above the heating limit C, is irrelevant in terms of regulating the heating. Since this area has the smallest radius of curvature of the heating curve (a, b), it is obvious that only the flatter part of the heating curve (a, b) can be used and therefore the heating curve (a, b) through a straight line (a ¹ , b ·) Can be approximated, this straight line forming the controller characteristic (a ', b ^r ) of the heating controller.

If a heating system with its controller is installed in a new building, the controller characteristic (a ¹ , b ') set during commissioning does not necessarily coincide with the required heating line (i.e. _o simplified heating curve), since the reference values (building characteristics, necessary radiator area) do not for the most part coincide can be calculated exactly.

Therefore, the position of the governor characteristic deviates from the location of the required Heizgeraden from and has to be corrected by actuating the above-mentioned adjustment members "For the decision, which is to be the adjustment members suitably used for the correction, it should be noted that the error from a wrong set steepness the closer the current outside temperature is to the intersection of the characteristic, the higher the outside temperature, the smaller the characteristic curve becomes.

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_ 5 -

On the other hand, the error of an incorrect level of the characteristic curve is constant and plays off against the possible one Errors resulting from incorrectly set slope play a smaller role, the further the current outside temperature away from the intersection of the curve, i.e. the lower the outside temperature.

Are the errors that occur most frequently when a heating system is started up for the first time? Experience values are known to the basic setting and depend on the associated climate range for each heating curve an outside temperature t .- ^ (according to Figo 3) can be determined above which is the cause of a setpoint deviation is more likely to be an incorrect position of the characteristic curve level is, while at lower outside temperatures the error is mainly in the steepness of the characteristic "

One of these outside temperatures t.-g, which is also an empirical value can be, equivalent variable is now derived according to the invention from the control loop and as Decision criterion for the selection of the correction more appropriate adjusting member used.

The most common variations in during commissioning set on the required position of Controller characteristic are _o According to be defined for each heating curve an outside temperature in estimating experience, and for regarding their higher temperatures to correct a parallel shift and respect her lower temperatures a slope correction. greater likelihood of success.

Different heating arrangement (building characteristics radiators / convectors), Z ₀ B ₀ a nearly constant error of the Lage'der heating curves result "Therefore, in respect to such as _o 2 (which different heating curves shows with the same design point and the setpoint) in Fig indicated, in order to adapt Control characteristic a parallel shift can be made.

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Since both errors are mostly present at the same time, it is obvious that it is not easy to decide whether a necessary correction is to be made by means of parallel shifts or changes in the slope is to achieve the ultimate goal of an optimal match between the controller characteristic and the required heating line. If the wrong setting element is selected, the desired room temperature would be given the current outside temperature also achieved, but at other outside temperatures the deviations are even greater »

In? Ig. 3 shows how the aforementioned outside temperature ΐ _ΑΕ »which is assigned to the so-called decision point PE can be determined by estimating the most frequently expected errors in the basic setting of the controller, depending on its size and type«,

The bridge circuit shown as an example in Fig. 4 of a conventional controller for outside temperature-dependent control of the flow temperature has a total of three parallel-connected, with supply voltage applied longitudinal connections 21, 22 and 23, of which the longitudinal connection 21 containing the resistors 1 and 4 is one half of a Wheatstone ' see bridge, while the other half of the bridge is formed by the two longitudinal connections 22 and 23, which contain the resistors 3, 10, 12 and 13 formed, the resistors 3 and 4 are temperature-dependent resistors, a co- temperature coefficient (both negative or both positive) "the resistance 3 senses the outdoor temperature, the resistor 4, the flow temperature of the heating medium", to which or between the resistors 3 and 10 _e 12 and 13 located nodes 42 and 43 are connected to a diagonal connection 31, which is connected as an adjustable voltage divider, which consists of the potentiometer 2 and 2, which is used as an adjusting element for the gradient of the characteristic curve

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the limiting resistor 11 exists, which is the lowest possible The steepness of the characteristic curve is determined »The tap 44 is led to one input of the differential amplifier 6, its other input is connected to the node 41 formed by the connection of the resistors 1 and 4 is.

The mode of operation of this conventional bridge circuit is as follows:

The bridge resistors are dimensioned so that at the same temperature of the two sensors 3 and 4, approximately the room temperature setpoint tng ·, -, (hereinafter referred to as the setpoint), the potentials of the nodes 41, 42 and 43 are identical the potential difference supplied to the amplifier 6 for each position of the slope setting element 2 is equal to 0, which means that in the coordinate system t ^ / t. all characteristics at point St ^. with the coordinates t ^ y «^ t» * ^ t _Rg -, -, converge (see also Fig. 1) · If the outside temperature t falls. from, so the sensing resistor 3, the corresponding one of the position of the transconductance setting member 2 proportion occurs by the change at the node 42, a potential shift on, at the tap 44 removed and supplied to the amplifier 6 _o If this controls a not signed actuator of known type in the V In other words, by raising the flow temperature t-rry via the flow sensor 4, the potential at the node is again equalized to that at the tap 44. A falling outside temperature t. therefore has an even greater increase in the flow temp emperature tr ™ - a result, the farther to the left, the tap of the transconductance setting member 2 in Figure 4 is located, i.e., "li" that each position corresponds to a certain characteristic curve slope (see FIG _o 1, characteristic curves. a ¹ and b ') o A change in the setting element 1 for parallel displacement, on the other hand, merely simulates a different flow temperature and raises the characteristic curves in the direction of the ordinate _o With the aid of these two setting elements, the adjustment of the controller characteristic

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(Left stop) and min <, /? ** £> + 40 ° G (Reehtsänsehlag) can be assigned «Becomes 2! .B ₀ adjusting element 2a open," -

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to the required, depending on the heating system and climate zone of the Different heating curves achieved at different locations.

In this conventional circuit, however, it is not possible to derive from the position of the slope potentiometer 2 ^ for which climatic area the system is intended «For example, characteristic curve b * could both ': For example, a convector heater with + 62 ° 0 max * ■ 'flow temperature at - 20 ° C outside temperature (= climate zone j - 20) as well as surface heating with a maximum door temperature of + 45 ° C in a climate zone of 0 °. !

According to the invention, the function of the usual slope potentiometer 2 is now corresponding to Pig. 5 on two different adjusting members 2a and 2b distributed. Are located yourself, "both sliders in the left stop, this corresponds analogous to Fig. 4 of the greatest possible gradient of the characteristic “Bs it is assumed that here at an outside temperature t. from 0 ° C to a flow temperature tr ™ · of + 110 ° C would »Viewed in isolation, the mode of operation of the two adjusting elements 2a and 2b is the same as that of the Slope potentiometer 2 in Fig. 4 ..

By moving the slider from 2a to the right, a flatter characteristic curve _{β is obtained} is present "at the right stop of the slider of Figure 2a this z _o B" a Temperatur.des outside sensor would be 3 of - 40 ° 0 required in the center position about - 20 ° C.

The potential difference now present between tap 45 and node 43 is in turn caused by the wiper subdivided on the setting member 2b so that each position has a corresponding door run temperature tg «· between max · + 110 ° C

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set, setting element 2b at the same time to »+ 62 °", the characteristic curve b ^{1 is obtained} after 3? ig _e 1, since a potential corresponding to a flow temperature of +110 C is only available at - 20 ° C outside sensor temperature at tap 45, but this is again divided by the position of the setting element 2b so that only a door running temperature of + 62 ° 0 is regulated. The same characteristic would also be obtained if 2a were set to "0 °", 2b to "+ 45 °".

As a first Yortell, this results in an easily understandable type of basic setting of the heating curve, since the coordinates of the design point of the heating system (max. Required flow temperature "fcjjy _max free lowest outside temperature t" occurring at the location of the system, corresponding to "climate zone") are set without first having to look for a digit corresponding to a polar coordinate by converting or comparing it with a manufacturer's diagram, which can also be different for the same slope setting depending on the device make.

Another advantage is that an electrical variable proportional to the respective climatic range can be derived from the position of the element 2a, with the aid of which, when _{the outside temperature is exceeded or fallen below,} that corresponding to the given climatic range for the selection of the setting element 1 or 2b, the decisive factor is that the link concerned can be made identifiable to the user of the system by means of a visual display or mechanically. The setting element 2a (setting the "climatic zone") is expediently designed as a trim potentiometer and is no longer changed after the initial setting

Based on the prop. 5 is the simplest, but the normal A circuit that meets the requirements for obtaining such a decision variable is explained «,

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- to - ■

A threshold switch 5 changes when exceeded!

a predetermined input spam difference abruptly j

its output variable iz.B »voltage from low to high or |

Resistance from low to high resistance) »Whose input j

voltage corresponds to the potential difference between the I.

Node 43 and tap 45 · As mentioned above, corresponds to;

the potential at node 43 corresponds to that of the nodes;

41 and 42, if outside sensor 3 and flow sensor 4 are approximately one;

Temperature of the room setpoint. When the J

The sensor resistor causes the outside temperature to fall below this value!

was 3 a potential shift, so that between the!

At nodes 42 and 43, a potential difference arises: which is proportional to the difference between the outside temperature and the room temperature setpoint ο Since the potential at tap 45
at the outside temperature that corresponds to the set

Climatic area, has the same specific value, '

on the other hand that at node 43 remains constant,. corresponds to the potential difference between these points

the relative deviation of the outside temperature from the room temperature.

temperature setpoint (heating curve intersection) based on!

the difference between the room setpoint and the climatic zone value _β ■

If the threshold switch is, for example, "on 2/3 of this max _o "

If the potential difference is set, it meets by changing i

its output size when falling below a corresponding;

the outside temperature the decision that the bin actuator j

2b should be used for correction. The decision i

temperature t. ™ would in this case be j according to the formula

η- ^(t RSoll " ¹¹ AmJn. (climatic zone) χ 2 " _tr ^ _m I

¹ TlSoIl - 3: ⁼ * AE given,;

e.g. for I.

Climatic zone = - 10 °, t _RSoll = + 20 °: t _AE = + 20- _{= (f} |

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In this simple circuit the decision \

temperature t.-g only in accordance with the set climatic zone i

certainly. It may now be desirable to trace the course of the _; Decision temperature t. ^, Not only from the climatic zone,

but also from a second influencing variable, ζ »B ₀ the \

Type of heating to make dependent. As a rough guideline for this \

the setting on potentiometer 2b (max.

Flow lock), as a setting to e.g.!

4-5 ° can be assigned to a surface heating or other j

on the other hand, a setting to 80 ° for radiator heating; lets close. In I ¹ Ig. 6 is one such circuit

shown, the ratio of the summers 7 and 8
corresponds to the ratio of the two influencing factors. i

A circuit is shown in FIG. 7 as a further possibility
shown in which by the additional longitudinal member 24
(Auxiliary bridge branch), consisting of resistors 9 and

14, the possibility is given to j

stepping, in relation to the set climatic area j

divided üPotential change with one of the room setpoint j

independent, freely selectable outside temperature j

to compare corresponding potential at node 46, »j

This enables an even better optimization of the i course of the decision temperature t. ™ over the entire. !

in the coming climatic zone area. Since this is not j

more the "setting elements already present in the control loop j

2a and possibly also 2b can be used, are j

electrically separated but mechanically coupled input \

Actuators 2a ¹ or 2b ¹ provided (! Andempotentiometer) «,>

5 also shows, for example, how j

through the output signal of the threshold switch 5 through ■

Excitation of a relay "17 with changeover contact 17" 3e after the j

Decision variable available at the input by switching on j

either lamp L1 or lamp L2 to the supply voltage \

the setting member 1 or Zh to be used is identified '

* Instead of the lamps, other known \

Electromechanical ^ elements (coupling, locking) arranged be" ..__ __ . ... ...... I.

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Claims (1)

DIPL-ING. HORST RSSE D! PL.-ING. PETERoKÖS / ErLc Q PATENT LAWYERS 3353 Bad Gandersheim, September 13, 1974 P.O. Box 129 Hohanhöfen S i «Telephone: (05382) 2842 "** Telegram address: Siedpatent Badgandersheim Our file no. 18/387 Aktiengesellschaft Adolph Saurer
Patent application dated September 13, 1974 Claims c Device in a weather-dependent flow temperature controller of a heating system to facilitate the adaptation of the controller characteristics of the flow temperature controller to given heating curves with at least two setting elements, characterized in that an electrical variable formed in a modified bridge circuit, which is used as a decision variable for an optimal for the respective climate area, for the choice of the setting element to be operated (1, parallel shift, or 2, slope) _{is equivalent to the decisive outside temperature (^ λ Ε} ), is used to identify the setting element to be operated, 2ο Device according to claim 1, characterized in that, in order to optimize the decision variable as a function of the respective climatic zone, the setting element (2) for the steepness of the characteristic curve is replaced by two setting elements (2a, 2b) connected in series, one of which (2a) for setting the characteristic curve Coordinate value of the climatic zone and the other (2b) is designed to set the associated coordinate element of the maximum flow temperature _c Rö / Hn, Bank account: Norddeutsche Landesbank, Bad Gandersheim branch, account no. 22.118.970 Postal checking account: Hanover 68715 509834/0538 ORIGINAL IMSPECTED 3. Set up after. Claim 1 or 2, characterized; shows that the decision variable · a coupling of ^: a common operating element optionally to one of the. two setting elements (1, parallel shift or 2,! slope) controlled 4. Device according to one of claims 1 "to 3, characterized in that it has an auxiliary bridge branch (24), by means of which the derivation of the decision variable; from a reference temperature independent of the characteristic line intersection or" room setpoint; can be selected, with as Stipulation
the set characteristic with the controller mechanically
connected adjusting elements that are galvanically separated from it
(2a ¹ , 2b ¹ ) are arranged »■ = - Patent attorneys
Dipl.-Inq. Horst Rose
Dipl.-Ing. Peter Kosel 509 834/0 538