Signal acquisition device for building controller

Abstract

The utility model discloses a signal acquisition device of a building controller, comprising an input protection circuit, the input end of which is connected with a signal to be acquired; the input end of the voltage acquisition circuit is connected with the output end of the input protection circuit; the input end of the voltage acquisition circuit is a voltage sampling point; the input end of the step-down circuit is connected with a voltage sampling point of the voltage acquisition circuit; the input end of the voltage following circuit is connected with the output end of the voltage reduction circuit, the output end of the voltage following circuit is connected to the micro-control unit, and the voltage following circuit sends the amplitude-adjusted signal to be collected to the micro-control unit.

Description

Technical Field

[0001] The utility model relates to the technical field of building controllers, and particularly relates to a signal acquisition device for a building controller. Background Art

[0002] An intelligent building integrates advanced scientific and technological aspects such as building technology, communication technology, computer technology, and control technology into an optimized whole. It has characteristics such as reasonable engineering investment, high equipment automation, scientific information management, efficient and high-quality services, flexible and convenient use, and safe and comfortable environment. It is a modern new building that can meet the development needs of the information society. At present, the market capacity of the domestic building automation system is very large, and energy conservation of the building heating and cooling source control system is particularly important.

[0003] Nowadays, users have higher and higher requirements for intelligent buildings, and there is an urgent need for a signal acquisition circuit to meet the needs of users for feedback of several different types of signals. Summary of the Utility Model

[0004] In view of this, the embodiment of the utility model provides a signal acquisition device for a building controller to solve the problem that the signal acquisition module adopted by the existing building controller cannot meet the needs of users.

[0005] The embodiment of the utility model provides a signal acquisition device for a building controller, including:

[0006] An input protection circuit, whose input end is connected to the signal to be acquired;

[0007] A voltage acquisition circuit, whose input end is connected to the output end of the input protection circuit; the input end of the voltage acquisition circuit and the output end of the input protection circuit are the voltage sampling points;

[0008] A step-down circuit, whose input end is connected to the voltage sampling point of the voltage acquisition circuit;

[0009] A voltage follower circuit, whose input end is connected to the output end of the step-down circuit, and the output end of the voltage follower circuit is connected to the micro control unit to send the signal to be acquired after amplitude adjustment to the micro control unit.

[0010] Optionally, the input protection circuit includes:

[0011] A fuse F12, one end of which is connected to the signal to be acquired;

[0012] A bipolar TVS diode GD9, one end of which is connected to one end of the fuse F12, and the other end of the bipolar TVS diode GD9 is grounded;

[0013] The unipolar TVS diode D48 has its positive electrode grounded, and the negative electrode of the unipolar TVS diode D48 is connected to the other end of the fuse F12;

[0014] The choke coil FL3 has one end connected to the first input terminal of the fuse F12, the second input terminal of the choke coil FL3 is grounded, and a capacitor C62 is connected in parallel between the first output terminal and the second output terminal of the choke coil FL3. The first output terminal of the choke coil FL3 is the voltage sampling point.

[0015] Optionally, the voltage acquisition circuit includes:

[0016] The resistor R111 has its first end connected to the output terminal of the input protection circuit, and the second end of the resistor R111 is connected to the drain of the MOS transistor Q19; the source of the MOS transistor Q19 is grounded, and the gate of the MOS transistor Q19 is connected to one end of the resistor R123, and the other end of the resistor R123 is connected to the first test signal terminal AI-C1;

[0017] The diode D52 is connected in parallel across the resistor R111; the positive electrode of the diode D52 is connected to the second end of the resistor R111, and the negative electrode of the diode D52 is connected to the first end of the resistor R111;

[0018] The resistor R112 has its first end connected to the first end of the resistor R111, and the second end of the resistor R112 is connected to the drain of the MOS transistor Q20; the source of the MOS transistor Q20 is connected to the DC 12V power supply;

[0019] The resistor R127 is connected in parallel across the gate and source of the MOS transistor Q20;

[0020] The triode Q15 has its emitter connected to the gate of the MOS transistor Q20, and the collector of the triode Q15 is grounded; a resistor R119 is connected in parallel between the base and the collector of the triode Q15;

[0021] The resistor R107 has one end connected to the base of the triode Q15, and the other end of the resistor R107 is connected to the second test signal terminal DI-C1;

[0022] Among them, the resistance value of the resistor R111 is 470Ω; the resistance value of the resistor R122 is 10kΩ.

[0023] Optionally, the buck circuit includes:

[0024] The resistor R131 has one end connected to the output terminal of the input protection circuit;

[0025] The resistor R135 has one end connected to the other end of the resistor R131;

[0026] The resistor R139 has one end connected to the other end of the resistor R135;

[0027] A resistor R143, one end of which is connected to the other end of a resistor R139, and the other end of the resistor R143 is grounded;

[0028] A capacitor C66, one end of which is connected to the other end of a resistor R131, and the other end of the capacitor C66 is grounded;

[0029] A diode D56, the negative electrode of which is connected to the other end of a resistor R135, and the positive electrode of the diode D56 is grounded;

[0030] Wherein, the other end of the resistor R139 is the output end of the buck circuit.

[0031] Optionally, the voltage follower circuit includes:

[0032] An operational amplifier U19, the positive input terminal 3 of which is connected to the output end of the buck circuit, the negative input terminal 4 of the operational amplifier U19 is connected to one end of a resistor R147, and the other end of the resistor R147 is connected to the output terminal 1 of the operational amplifier U19; the positive power input terminal 5 of the operational amplifier is connected to a DC 3.3V power supply; a capacitor C70, one end of which is connected to the positive power input terminal 5 of the operational amplifier, and the other end of the capacitor C70 is grounded; the negative power input terminal 2 of the operational amplifier is grounded;

[0033] A resistor R151, one end of which is connected to the output terminal 1 of the operational amplifier U19, and the other end of which is connected to the micro control unit;

[0034] A diode D60, the positive electrode of which is connected to the other end of the resistor R151, and the negative electrode of the diode D60 is connected to the DC 3.3V power supply.

[0035] Optionally, when a resistor to be measured is connected to the input end of the input protection circuit, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a high level.

[0036] Optionally, when a voltage to be measured is connected to the input end of the input protection circuit, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a low level.

[0037] Optionally, when a current to be measured is connected to the input end of the input protection circuit, the first test signal terminal AI-C1 outputs a high level, and the second test signal terminal DI-C1 outputs a low level.

[0038] Optionally, when a digital input signal is connected to the input end of the input protection circuit, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a high level.

[0039] The beneficial effects of the present utility model:

[0040] An embodiment of the utility model provides a signal acquisition device for a building controller. Among them, by changing the high / low level output of the first test signal terminal AI-C1 and the second test signal terminal DI-C1 for state switching, the detected signal UIN is corrected and output as UOUT, reducing the measurement error caused by the too large difference in resistance values in the circuit and improving the detection accuracy.

[0041] In practical applications, a plurality of sampling terminals are provided. Between each sampling terminal and the microcontroller, there is a signal acquisition device for a building controller provided by the embodiment of the utility model. On the one hand, for different types of sampling signals, the corresponding output modes of the first test signal terminal AI-C1 and the second test signal terminal DI-C1 are selected. On the other hand, due to the provision of a plurality of sampling terminals, unified wiring of several feedback signals of the building controller is realized, facilitating communication transmission. Description of the Drawings

[0042] The features and advantages of the utility model will be more clearly understood by referring to the accompanying drawings. The drawings are schematic and should not be construed as imposing any limitation on the utility model. In the drawings:

[0043] Figure 1 The circuit diagram of a signal acquisition device for a building controller in an embodiment of the utility model is shown. Detailed Embodiment

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the utility model clearer, the technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the utility model. Obviously, the described embodiments are some but not all of the embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the utility model.

[0045] An embodiment of the utility model provides a signal acquisition device for a building controller, including an input protection circuit, a voltage acquisition circuit, a step-down circuit, and a voltage follower circuit. Among them: the input end of the input protection circuit is connected to the signal to be acquired; the input end of the voltage acquisition circuit is connected to the output end of the input protection circuit; the input end of the voltage acquisition circuit and the output end of the input protection circuit are the voltage sampling points; the input end of the step-down circuit is connected to the voltage sampling point of the voltage acquisition circuit; the input end of the voltage follower circuit is connected to the output end of the step-down circuit, and the output end of the voltage follower circuit is connected to the micro control unit to send the signal to be acquired after amplitude adjustment to the micro control unit.

[0046] As Figure 1 shown, the input protection circuit includes:

[0047] A fuse F12, one end of which is connected to the signal to be collected;

[0048] A bipolar TVS diode GD9, one end of which is connected to one end of the fuse F12, and the other end of the bipolar TVS diode GD9 is grounded;

[0049] A unipolar TVS diode D48, the positive electrode of which is grounded, and the negative electrode of the unipolar TVS diode D48 is connected to the other end of the fuse F12;

[0050] An inductor FL3, one end of which is connected to the first input terminal of the fuse F12, the second input terminal of the inductor FL3 is grounded, a capacitor C62 is connected in parallel between the first output terminal and the second output terminal of the inductor FL3, and the first output terminal of the inductor FL3 is the voltage sampling point.

[0051] The voltage acquisition circuit includes:

[0052] A resistor R111, the first end of which is connected to the output terminal of the input protection circuit, and the second end of the resistor R111 is connected to the drain of the MOS transistor Q19; the source of the MOS transistor Q19 is grounded, the gate of the MOS transistor Q19 is connected to one end of a resistor R123, and the other end of the resistor R123 is connected to the first test signal terminal AI-C1;

[0053] A diode D52 is connected in parallel across the resistor R111; the positive electrode of the diode D52 is connected to the second end of the resistor R111, and the negative electrode of the diode D52 is connected to the first end of the resistor R111;

[0054] A resistor R112, the first end of which is connected to the first end of the resistor R111, and the second end of the resistor R112 is connected to the drain of the MOS transistor Q20; the source of the MOS transistor Q20 is connected to the DC 12V power supply;

[0055] A resistor R127 is connected in parallel across the gate and the source of the MOS transistor Q20;

[0056] A triode Q15, the emitter of which is connected to the gate of the MOS transistor Q20, and the collector of the triode Q15 is grounded; a resistor R119 is connected in parallel between the base and the collector of the triode Q15;

[0057] A resistor R107, one end of which is connected to the base of the triode Q15, and the other end of the resistor R107 is connected to the second test signal terminal DI-C1;

[0058] Wherein, the resistance value of the resistor R111 is 470Ω; the resistance value of the resistor R122 is 10kΩ.

[0059] The buck circuit includes:

[0060] A resistor R131, one end of which is connected to the output end of the protection circuit;

[0061] A resistor R135, one end of which is connected to the other end of the resistor R131;

[0062] A resistor R139, one end of which is connected to the other end of the resistor R135;

[0063] A resistor R143, one end of which is connected to the other end of the resistor R139, and the other end of the resistor R143 is grounded;

[0064] A capacitor C66, one end of which is connected to the other end of the resistor R131, and the other end of the capacitor C66 is grounded;

[0065] A diode D56, the negative electrode of which is connected to the other end of the resistor R135, and the positive electrode of the diode D56 is grounded;

[0066] Wherein, the other end of the resistor R139 is the output end of the buck circuit.

[0067] The voltage follower circuit includes:

[0068] An operational amplifier U19, the positive input terminal 3 of which is connected to the output end of the buck circuit, the negative input terminal 4 of the operational amplifier U19 is connected to one end of a resistor R147, and the other end of the resistor R147 is connected to the output terminal 1 of the operational amplifier U19; the positive power input terminal 5 of the operational amplifier is connected to a DC 3.3V power supply; a capacitor C70, one end of which is connected to the positive power input terminal 5 of the operational amplifier, and the other end of the capacitor C70 is grounded; the negative power input terminal 2 of the operational amplifier is grounded;

[0069] A resistor R151, one end of which is connected to the output terminal 1 of the operational amplifier U19, and the other end of which is connected to the micro control unit;

[0070] A diode D60, the positive electrode of which is connected to the other end of the resistor R151, and the negative electrode of the diode D60 is connected to the DC 3.3V power supply. The diode D60 is used to protect the output voltage of the resistor R151 from being too high.

[0071] As an optional implementation manner, when a resistor to be measured is connected to the input end of the input protection circuit, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a high level.

[0072] As an optional implementation manner, when a voltage to be measured is connected to the input end of the input protection circuit, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a low level.

[0073] As an alternative embodiment, when the current to be measured is connected to the input end of the input protection circuit, the first test signal terminal AI-C1 outputs a high level, and the second test signal terminal DI-C1 outputs a low level.

[0074] As an alternative embodiment, when a digital input signal is connected to the input end of the input protection circuit, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a high level.

[0075] The following Figure 1 explains the principle of the circuit:

[0076] Make the first test signal terminal AI-C1 output a low level, and the second test signal terminal DI-C1 output a high level. At this time, the triode Q15 conducts, the gate of the MOS transistor Q20 is grounded to a low level, and the MOS transistor Q20 conducts. The MOS transistor Q19 is cut off. The potential U of the sampling voltage point IN-1 with respect to the ground is obtained 1 .

[0077] Make the first test signal terminal AI-C1 output a high level, and the second test signal terminal DI-C1 output a high level. At this time, the MOS transistor Q19 conducts, and the potential U of the sampling voltage point IN-1 with respect to the ground is obtained 2 . U 2 The actual value is the voltage division across the resistor R111. Since the current flowing into the node is 0, there is

[0078]

[0079] Record the actual voltage sampling values as U 1S (corresponding to the first test signal terminal AI-C1 outputting a low level and the second test signal terminal DI-C1 outputting a high level) and U 2S (corresponding to the first test signal terminal AI-C1 outputting a high level and the second test signal terminal DI-C1 outputting a high level). Record the theoretically calculated voltage values as U 1 and U 2 .

[0080] Using the circuit of the signal acquisition device provided in this embodiment, configure the types of acquired signal access as: measuring resistance, measuring 0 - 10V, measuring 4 - 20mA, and DI input, as shown in Table 1.

[0081] Table 1 Signal sampling functions and corresponding test signal configurations

[0082] Function AI_C1 DI_C1 Measuring resistance Low High Measuring 0 - 10V Low Low Measuring 4 - 20mA High Low DI input Low High

[0083] In practical applications, several sampling terminals are set, and between each sampling terminal and the microcontroller, there is a signal acquisition device for building controllers provided by the present utility model. On the one hand, for different types of sampling signals, the corresponding output modes of the first test signal terminal AI-C1 and the second test signal terminal DI-C1 are selected. On the other hand, due to the setting of several sampling terminals, the unified wiring of several feedback signals of the building controller is realized, which is convenient for communication transmission.

[0084] In addition, the output voltage is adjusted:

[0085]

[0086] Obtain

[0087]

[0088] where UIN is the signal before correction, and UOUT is the output voltage value after correction.

[0089] After adjusting the voltage output, the voltage measurement accuracy can be improved.

[0090] Calculate the resistance value to be measured through the corrected output voltage:

[0091]

[0092] When the first test signal terminal AI-C1 outputs a low level and the second test signal terminal DI-C1 outputs a high level, the resistor R111 (470Ω) is disconnected. At this time, IN-1 is at a high level with respect to the ground, that is, U 1S is a relatively large value, approximately 10V. When the first test signal terminal AI-C1 outputs a high level and the second test signal terminal DI-C1 outputs a high level, one end of the resistor R111 is grounded. At this time, IN-1 is at a low level with respect to the ground, that is, U 2S is a relatively small value, approximately 0.6V. If the output voltage is not adjusted, due to the inverse proportional relationship between the resistance value and the voltage value in formula (2), when measuring small resistors and large resistors, the change in the detected voltage will be very small, and the change range of the calculated resistance value to be measured will be very large. That is to say, the voltage error in multiple detections is very small, but in fact, the resistance value error is very large. Introducing formula (1) to correct the voltage, that is, correcting the voltage near 0.6V and 10V, thus reducing the measurement error. That is, the originally detected signal value UIN is corrected and output as UOUT, reducing the measurement error caused by the too large difference in resistance values in the circuit and improving the detection accuracy.

[0093] Although embodiments of the present utility model have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present utility model, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A signal acquisition device for a building controller, characterized in that: include: An input protection circuit, the input end of which is connected to the signal to be collected; A voltage collection circuit, whose input end is connected to the output end of the input protection circuit; the input end of the voltage collection circuit and the output end of the input protection circuit are voltage sampling points; A step-down circuit, whose input end is connected to the voltage sampling point of the voltage collection circuit; A voltage follower circuit, whose input end is connected to the output end of the step-down circuit, and whose output end is connected to a micro control unit, sends the signal to be collected after amplitude adjustment to the micro control unit.

2. The signal acquisition device for a building controller according to claim 1, characterized in that: The input protection circuit comprises: A fuse F12, one end of which is connected to the signal to be collected; A bipolar TVS diode GD9, one end of which is connected to one end of the fuse F12, and the other end of the bipolar TVS diode GD9 is grounded; A unipolar TVS diode D48, whose positive electrode is grounded, and whose cathode is connected to the other end of the fuse F12; One end of the choke FL3 is connected to the first input end of the fuse F12, the second input end of the choke FL3 is grounded, a capacitor C62 is connected in parallel between the first output end and the second output end of the choke FL3, and the first output end of the choke FL3 is the voltage sampling point.

3. The signal acquisition device for a building controller according to claim 1, characterized in that: The voltage acquisition circuit comprises: A resistor R111, a first end of which is connected to the output end of the input protection circuit, a second end of which is connected to the drain of the MOS transistor Q19; a source of the MOS transistor Q19 is grounded, a gate of the MOS transistor Q19 is connected to one end of a resistor R123, and the other end of the resistor R123 is connected to the first test signal terminal AI-C1; A diode D52 is connected in parallel to both ends of the resistor R111; the anode of the diode D52 is connected to the second end of the resistor R111, and the cathode of the diode D52 is connected to the first end of the resistor R111; A resistor R112, a first end of which is connected to the first end of the resistor R111, and a second end of the resistor R112 is connected to the drain of the MOS transistor Q20; a source of the MOS transistor Q20 is connected to a DC 12V power supply; A resistor R127 is connected in parallel to the gate and source of the MOS tube Q20; A transistor Q15, whose emitter is connected to the gate of the MOS transistor Q20, and whose collector is grounded; a resistor R119 is connected in parallel between the base and collector of the transistor Q15; A resistor R107, one end of which is connected to the base of the transistor Q15, and the other end of the resistor R107 is connected to the second test signal terminal DI-C1; The resistance value of the resistor R111 is 470Ω; the resistance value of the resistor R122 is 10kΩ.

4. The signal acquisition device for a building controller according to claim 1, characterized in that: The step-down circuit comprises: A resistor R131, one end of which is connected to the output end of the input protection circuit; a resistor R135, one end of which is connected to the other end of the resistor R131; a resistor R139, one end of which is connected to the other end of the resistor R135; A resistor R143, one end of which is connected to the other end of the resistor R139, and the other end of the resistor R143 is grounded; A capacitor C66, one end of which is connected to the other end of the resistor R131, and the other end of the capacitor C66 is grounded; a diode D56, a cathode of which is connected to the other end of the resistor R135, and an anode of the diode D56 is grounded; The other end of the resistor R139 is the output end of the step-down circuit.

5. The signal acquisition device for a building controller according to claim 1, characterized in that: The voltage follower circuit comprises: Operational amplifier U19, whose positive input terminal 3 pin is connected to the output end of the step-down circuit, whose negative input terminal 4 pin is connected to one end of resistor R147, whose other end is connected to output terminal 1 pin of the operational amplifier U19; whose power supply positive input terminal 5 pin is connected to a DC 3.3V power supply; whose capacitor C70 has one end connected to the power supply positive input terminal 5 pin of the operational amplifier, whose other end is grounded; whose power supply negative input terminal 2 pin of the operational amplifier is grounded; A resistor R151, one end of which is connected to the output terminal 1 of the operational amplifier U19, and the other end of which is connected to the micro control unit; The diode D60 has an anode connected to the other end of the resistor R151, and a cathode connected to a DC 3.3V power supply.

6. The signal acquisition device for a building controller according to claim 3, characterized in that: When the input terminal of the input protection circuit is connected to the resistance to be measured, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a high level.

7. The signal acquisition device for a building controller according to claim 3, characterized in that: When the input terminal of the input protection circuit is connected to the voltage to be measured, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a low level.

8. The signal acquisition device for a building controller according to claim 3, characterized in that: When the input terminal of the input protection circuit is connected to the current to be measured, the first test signal terminal AI-C1 outputs a high level, and the second test signal terminal DI-C1 outputs a low level.

9. The signal acquisition device for a building controller according to claim 3, characterized in that: When the input terminal of the input protection circuit is connected to a digital input signal, the first test signal terminal AI-C1 outputs a low level, and the second test signal terminal DI-C1 outputs a high level.

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