CN207540686U - A kind of 16 road temperature polling instruments - Google Patents

Abstract

The utility model is related to logging fields, especially a kind of 16 road temperature polling instruments, it is using microcontroller as core, the microcontroller carries out temperature value circling measurment, data calculate, data are shown while detects alarm condition, input through keyboard and communication data and makes corresponding processing, the SCM peripheral is connected with temperature sensor and its signal processing circuit, man-machine interface, communication interface, warning output and power supply, and the wherein signal processing circuit of temperature sensor is made of signal selecting circuit, signal amplification circuit, A/D conversion circuits.The utility model greatly reduces the quantity of measuring instrumentss, has many advantages, such as that observing and controlling is precise and stable and strong antijamming capability, compact to design, at low cost, powerful, and the scope of application is very extensive.

Description

A kind of 16 road temperature polling instruments

Technical field

The utility model is related to logging field, specific field is a kind of 16 road temperature polling instruments.

Background technology

With computer, the fast development of microelectric technique, microcontroller is since its integrated level is high, function is strong, small, anti- The advantages that interference performance, is widely used in industrial control field.Also earth-shaking variation, mesh are occurring for measuring instrument instrument None does not use microcontroller during preceding intelligent instrumentation design.Temperature survey is widely used general in field of industrial production, and passes The temperature monitor of system generally can only single-point detection and only display function.It is big in some operating radius, the industry of measuring point dispersion Occasion, it is necessary to which, by a kind of more circling measurments, the measuring instrumentss of centralized management can realize alarm, teletransmission, control, data note The functions such as record, automatic running is without human intervention.

Utility model content

It is precise and stable and anti-interference with observing and controlling the purpose of this utility model is to provide a kind of 16 road temperature polling instruments The advantages of ability is strong.

To achieve the above object, on the one hand the utility model provides following technical solution：A kind of 16 road temperature polling instruments, It is characterized in that, it is using microcontroller as core, the microcontroller carries out temperature value circling measurment, data calculate, data are shown, It detects alarm condition, input through keyboard and communication data simultaneously and makes corresponding processing, the SCM peripheral is connected with temperature Sensor and its signal processing circuit, man-machine interface, communication interface, warning output and power supply, wherein temperature sensor Signal processing circuit is made of signal selecting circuit, signal amplification circuit, A/D conversion circuits.

Preferably, it is main control chip that the microcontroller, which selects STC15F2K60S2,.

Preferably, the temperature sensor selects Pt100 platinum resistance, totally No. 16 temperature sensor.

Preferably, the input power of the power circuit is by TOP414 switches and high frequency transformer transformation, then passes through TOP414 is switched and high frequency transformer transformation, using rectification, capacitor filtering and the flat wave of inductance, exports direct current.High frequency transformation Device secondary side has 3 windings, 2 road output powers, and another way provides power supply for backfeed loop.

Compared with prior art, the beneficial effects of the utility model are：The quantity of measuring instrumentss is greatly reduced, has and surveys The advantages that controlling precise and stable and strong antijamming capability, it is compact to design, at low cost, powerful, and the scope of application is very extensive.

Description of the drawings

Fig. 1 is the functional block diagram of the utility model multipath temperature patrol inspection instrument；

Fig. 2 is the signal selecting circuit of the utility model and the circuit diagram of signal amplification circuit；

Fig. 3 is the circuit diagram of the A/D conversion circuits of the utility model；

Fig. 4 is the power circuit diagram of the utility model；

Fig. 5 is the man-machine interface circuit figure of the utility model；

Fig. 6 is the warning output of the utility model and telecommunication circuit schematic diagram.

Specific embodiment

The following is a combination of the drawings in the embodiments of the present utility model, and the technical scheme in the embodiment of the utility model is carried out It clearly and completely describes, it is clear that the described embodiments are only a part of the embodiments of the utility model rather than whole Embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are without making creative work All other embodiments obtained shall fall within the protection scope of the present invention.

Referring to Fig. 1, the utility model provides a kind of technical solution：16 road temperature polling instruments, using microcontroller as core, Microcontroller mainly carries out temperature value circling measurment, data calculate, data are shown while detect alarm condition, input through keyboard And communication data and corresponding processing is made, SCM peripheral has temperature sensor and its signal processing circuit, man-machine interface, logical Believe interface, warning output and power supply, the wherein signal processing circuit of temperature sensor is amplified by signal selecting circuit, signal Circuit, A/D conversion circuits composition.

It is main control chip that microcontroller, which selects STC15F2K60S2, in the present embodiment, which has the characteristics that：It is internal Integrated high-precision RC clocks, and it is optional from 5~35MHz；Reset circuit is internally integrated, 8 grades of reset threshold voltages are optional；Inside collection Into E2PROM, for preserving user setting parameter and calibration parameter.Temperature sensor selects Pt100 platinum resistance, totally 16 tunnel temperature Sensor is the temperature sensor that a kind of resistance value changes with variation of ambient temperature, because it is with stability is good, precision High, the advantages that temperature-measuring range is big, and be widely used.

The signal selecting circuit and signal amplification circuit of signal processing circuit are as shown in Fig. 2, by 17 signal deteching circuits It forms (the 1st, the 2nd and the 17th is only drawn since the space of a whole page is limited, in figure), realizes 16 road Pt100 temperature sensors are defeated The resistance signal gone out is converted to voltage signal.Wherein the 1st tunnel does not have external Pt100 sensors, and the purpose for setting it is for system No-voltage and reference voltage are provided, for making up the error of operational amplifier amplification factor, the principle of remaining 16 circuits is complete Unanimously.2 voltage signals are generated per road and realize timesharing gating, 2 CD4067 by 2 16 × 1 multi-channel switcher CD4067 respectively Common end and no-voltage, reference voltage gated again by analog switch CD4051.8 data latches 74LS273 are used for I/O mouthfuls Extension, control the address code of variable connector.Voltage signal amplification uses the operational amplifier OP07 of low zero shift, in order to adapt to Different input signals, OP07 and analog switch CD4051 form a programmable gain amplifier.Gain is controlled by CD4051 Analog switch and resistance are formed, by realizing the amplification factor different to input signal to the control of CD4051 address codes.

A/D conversion circuits in the present embodiment have 4 half as shown in figure 3, selecting TLC7135 double integration A/D converters Precision (being equivalent to 14 A/D), automatic zero adjustment, auto polarity output, the quasi- voltage of single benchmark, dynamic word bit scanning binary-coded decimal it is defeated Go out, interference resistance it is strong, quasi- voltage, the output of dynamic word bit scanning binary-coded decimal, interference resistance are strong, the features such as stability is good.Blemish in an otherwise perfect thing Be its conversion accuracy dependent on the time of integration, therefore conversion speed is relatively low.Although present mainstream is that successive approximation A/D turns Parallel operation, but high-precision (>12) successive approximation A/D prices it is very high.TLC7135 relies on the low advantage with high accuracy of its price, Still favored now by numerous designers.TCL7135 is more using data, and operation principle is not just done excessively tell about herein.

Switching Power Supply of the power supply of the present embodiment based on TOP414, TOP414 are that set pulse signal control circuit and power are opened Device MOSEFT is closed in the power supply control chip of one.There is high integration, simple peripheral circuit, high efficiency can be formed The isolation type switching power supply of no industrial frequency transformer.As shown in Figure 4, input power is become by TOP414 switches and high frequency transformer Pressure, then by TOP414 switches and high frequency transformer transformation, using rectification, capacitor filtering and the flat wave of inductance, export direct current. High frequency transformer secondary side has 3 windings, 2 road output powers, and another way provides power supply for backfeed loop.Backfeed loop is from output End carries out voltage sampling, Pulse Width Control is controlled to switch on-off by optocoupler, adjusts output power.Power supply circuit is distinguished 5V power supplys are provided to circuit system, 12V power supplys are provided to alarm and telecommunication circuit.Two-way out-put supply is mutually isolated.

As shown in figure 5,4 Digital sum pipes respectively have 8 display segments, the identical section of bits per inch code pipe connects together for man-machine interface, Section driving is uniformly carried out by P0 ports, and the common-anode of each charactron is then driven by another I/O.P2.4 is used to drive LED light common end, P2.5 detect key-press input for timesharing.The mentality of designing of driver, P2.0-3 port controlling triodes Q₁, Q₂, Q₃, Q₄It opens in turn.Such as P2.0 output low levels, triode Q1 conductings, charactron DS1 are lighted, P0 port controllings are shown Show corresponding number, for LED1 states if you need to light, otherwise P2.4 output low levels export high level.Detect P2.5 ports simultaneously Input such as illustrates button S for high level₁It is pressed.It, can be in microcontroller in order to strictly ensure period in turn and display time Dynamic Announce and detection are carried out in timer interrupt service program.

As shown in fig. 6, in order to avoid the surge impact and noise jamming of peripheral equipment, warning output and telecommunication circuit are with being Circuit of uniting is completely isolated, does not have any conduction connection physically between ground connection and circuit.Relay K₁、K₂With Mr. Yu road temperature When degree is more than the alarming value set, mechanical contacts signal is exported, can such as connect sound, light warning device.485 communication interfaces of RS This instrument can be brought into 485 networks of RS of bus topology, to improve the Centralized Monitoring ability for measuring network.In order to carry High 485 communication speed the design of RS employs the zero propagation circuit for sending and receiving automatic conversion.If it sends as low level, DE/ RE is high level, and sending allows, and at this time since D pins are grounded, the output terminals A of MAX1487 chips, B, which are generated, represents low level Differential signal.If sending high level, DE/RE is low level, and A, B end of MAX1487 chips are in high-impedance state.Resistance R is depended at this time₃₂ And R₃₅Drop-down and pull-up effect, make in bus generate represent high level differential signal.As can be seen from the above analysis, in half-duplex Under the mode for transmitting data, program need not control DE/RE, the conversion that hardware completion sends and receivees.

While there has been shown and described that the embodiment of the utility model, for the ordinary skill in the art, It is appreciated that can these embodiments be carried out with a variety of variations in the case of the principle and spirit for not departing from the utility model, repaiied Change, replace and modification, the scope of the utility model are defined by the appended claims and the equivalents thereof.

Claims (4)

1. a kind of 16 road temperature polling instruments, which is characterized in that, using microcontroller as core, the microcontroller carries out temperature value for it Circling measurment, data calculate, data show while detect alarm condition, input through keyboard and communication data and make corresponding place Reason, the SCM peripheral are connected with temperature sensor and its signal processing circuit, man-machine interface, communication interface, warning output And power supply, the wherein signal processing circuit of temperature sensor convert electricity by signal selecting circuit, signal amplification circuit, A/D Road forms, and the signal processing circuit connects 17 signal deteching circuits, and each signal deteching circuit generates 2 voltage letters Timesharing gating is realized by 2 16 × 1 multi-channel switcher CD4067, the common end of 2 CD4067 and no-voltage, ginseng number respectively Voltage is examined to be gated by analog switch CD4051 again.

2. a kind of 16 road temperature polling instrument according to claim 1, it is characterised in that：The microcontroller is selected STC15F2K60S2 is main control chip.

3. a kind of 16 road temperature polling instrument according to claim 1, it is characterised in that：The temperature sensor is selected Pt100 platinum resistance, totally No. 16 temperature sensor.

4. a kind of 16 road temperature polling instrument according to claim 1, it is characterised in that：The microcontroller is also associated with electricity Source circuit, the input power of the power circuit are switched by TOP414 switches and high frequency transformer transformation, then by TOP414 With high frequency transformer transformation, using rectification, capacitor filtering and the flat wave of inductance, direct current is exported, the high frequency transformer is secondary There are 3 windings, 2 road output powers in side.