Summary of the invention
Use terminal to be unlikely to surpass the use terminal damage that the scope of application causes in order to protect because of electric current; the utility model provides a kind of supervising device to voltage input and current output, and this supervising device adopts the digital voltage signal V to receiving in central processing unit
InCarry out the operating voltage V of one 12 bit value of differential ference spiral acquisition
OutThis operating voltage V
OutOn the one hand as input voltage of current conversion, on the other hand with operating voltage V
OutWith voltage threshold P
InCompare and obtain alarm voltage, thereby the effect of early warning and protection is played in realization to the damage of using the terminal overcurrent to cause.
A kind of supervising device of the present utility model to voltage input and current output, this supervising device includes a housing, and is installed in the circuit board in the housing; Be provided with voltage interface (J3), current interface (J2) and remote alarm interface (J6) on the top panel of housing, the right panel of housing is provided with power interface (J1), and the front panel of housing is provided with LCD display and keyboard;
Power interface (J1) is used for being connected with the direct current of 220V;
Voltage interface (J3) is used for and can exports 0~5V analog voltage signal V
VoltageProduct;
Current interface (J2) is used for being connected with using end product;
Remote alarm interface (J6) be used to provide audible alarm;
Circuit board includes:
One central processing unit, range S and ratio K and the digital voltage signal V of this central processing unit to setting among the command information INF that receives
InCarry out difference processing and obtain the operating voltage V of 12 bit values
OutThis operating voltage V
OutExport the demonstration of the enterprising line number font of LCD MODULE formula on the one hand to; This operating voltage V on the other hand
OutBe output to alarm output module; In alarm output module, this operating voltage V
OutWith voltage threshold P
InCompare, work as V
Out〉=P
InThe time, alarm output module produces alarm signal and carries out alarm; Work as V
Out<P
InThe time, with the operating voltage V of 12 bit values
OutExport to D/A converter module;
One analog-to-digital conversion module, this analog-to-digital conversion module are used for the 0~5V analog signal V with the outside input
VoltageConvert digital voltage signal V to
InOffering central processing unit handles;
The 12 bit value operating voltage V that one D/A converter module, this D/A converter module will receive
OutCarry out exporting after the digital-to-analogue conversion current signal I of 4~20mA
Electric current
One alarm output module, this alarm output module is used for the output of warning message;
One keyboard issues command information INF by this keyboard to central processing unit, and this order information INF includes range S, ratio K and voltage threshold P
In
One LCD MODULE, this LCD MODULE are used to carry out the information that digital form shows each input, output.
The advantage of a kind of supervising device to voltage input and current output of the present utility model is:
(1) 0~5V analog signal V that the outside is imported
VoltageCarry out providing digital voltage signal V for central processing unit after the analog-to-digital conversion
In
(2) the digital voltage signal V of difference algorithm to receiving of application C language compilation in central processing unit
InHandle, improved precision the input voltage monitoring.
(3) (command information INF includes range S, ratio K and voltage threshold P to issue command information INF by keyboard operation
In), this command information INF can change voluntarily, set according to the actual demand of using terminal, has improved the operating flexibility of the utility model supervising device.
(4) 0~5V analog signal V
VoltageInput, and 4~20mA current signal I
Electric currentOutput, be common analog signal in the commercial Application now, solved stability and the required precision of using terminal that electric current is needed, thereby protected the use terminal effectively.
Embodiment
Below in conjunction with accompanying drawing the utility model is described in further detail.
Referring to shown in Figure 1, the supervising device of voltage input and current output of the present utility model is mounted in and uses terminal and can export 0~5V analog signal V
VoltageEquipment between.This supervising device can be protected and use terminal to be unlikely to cause damage because of electric current surpasses the scope of application.
Shown in Figure 1A, the supervising device of voltage input and current output of the present utility model includes a housing, and is installed in the circuit board in the housing.On the top panel of housing, be provided with voltage interface J3, current interface J2 and remote alarm interface J6, the right panel of housing is provided with power interface J1, the front panel of housing be provided with LCD display and keyboard (0-9 numeral arranged on this keyboard, and commonly used as determine, key such as cancellation).LCD display is used to show that (command information INF includes range S, ratio K and voltage threshold P to the command information INF that issues by keyboard
In), the easy operating person to the actual demand of using end product change voluntarily, visual when setting.Power interface J1 is used for being connected with the direct current of 220V.Voltage interface J3 is used for and can exports 0~5V analog voltage signal V
VoltageProduct.Current interface J2 is used for being connected with using end product.Remote alarm interface J6 is used for and is connected as loudspeaker, and audible alarm is provided.
Referring to shown in Figure 2, the board structure of circuit figure of a kind of supervising device to voltage input and current output of the present utility model includes on this circuit board:
One central processing unit, range S and ratio K and the digital voltage signal V of this central processing unit to setting among the command information INF that receives
InCarry out difference processing and obtain the operating voltage V of 12 bit values
OutThis operating voltage V
OutExport the demonstration of the enterprising line number font of LCD MODULE (LCD) formula on the one hand to; This operating voltage V on the other hand
OutBe output to alarm output module; In alarm output module, this operating voltage V
OutWith voltage threshold P
InCompare, work as V
Out〉=P
InThe time, alarm output module produces alarm signal and carries out alarm; Work as V
Out<P
InThe time, with the operating voltage V of 12 bit values
OutExport to D/A converter module;
One analog-to-digital conversion module, this analog-to-digital conversion module are used for the 0~5V analog signal V with the outside input
VoltageConvert digital voltage signal V to
InOffering central processing unit handles;
The 12 bit value operating voltage V that one D/A converter module, this D/A converter module will receive
OutCarry out exporting after the digital-to-analogue conversion current signal I of 4~20mA
Electric current
One alarm output module, this alarm output module is used for the output of warning message;
One keyboard issues command information INF by this keyboard to central processing unit, and this order information INF includes range S, ratio K and voltage threshold P
In
One LCD MODULE, this LCD MODULE are used to carry out the information that digital form shows each input, output.
The supervising device of a kind of voltage input and current output of the present utility model, its central processing unit is chosen the ATmega128 chip, modulus conversion chip in the analog-to-digital conversion module is chosen the MAX187 chip, analog-digital chip in the D/A converter module is chosen the MAX5712 chip, and the voltage in the D/A converter module changes the electric current chip and chooses the ISOEM-U1-P1-O1 chip.The circuit of this supervising device under each chip portfolio of choosing connects:
Shown in Fig. 3 A, Fig. 3 B, Fig. 3 C, 8 terminals of 10 ends of central processing unit U1~17 ends join with 1 end~8 ends of the interface J4 of keyboard respectively, realize that keyboard is connected on the central processing unit U1; Keyboard is connected with central processing unit, has realized issuing command information INF by keyboard operation to central processing unit.In the utility model, described command information INF includes the voltage threshold P when reporting to the police at least
In, by keyboard operation the range S (0~9999) of input voltage is set, under alarm condition as analog-to-digital conversion module input voltage V
InBe lower than voltage threshold P
InIn time, sounds all clear (resetting), by keyboard output current I be set by operation keyboard
Electric currentRatio K (0<K≤9.9).In the utility model, the voltage of 220V enters to exchange through power interface J1 to be changeed among the direct current chip U5, changes direct current chip U5 through this interchange and converts 5V voltage to as the supervising device use of VCC for whole voltage input and current output of the present utility model.
Shown in Fig. 3 D, 8 terminals of 25 ends of central processing unit U1~32 ends join with 7 ends~14 ends of the interface J5 of LCD MODULE respectively, 36 ends of central processing unit U1,37 ends, 38 ends respectively with 4 ends of LCD interface J5,5 ends, 6 ends join, the 2 termination 5V power supplys of the interface J5 of LCD MODULE, 3 ends are connected on 2 ends of adjustable resistance R27, the 1 termination 5V power supply of adjustable resistance R27, the 3 end ground connection of adjustable resistance R27,1 end of the interface J5 of LCD MODULE is connected on 3 ends of adjustable resistance R27, the 16 end ground connection of the interface J5 of LCD MODULE, 15 ends of the interface J5 of LCD MODULE connect the 5V power supply after resistance R 32; LCD MODULE is connected with central processing unit, has realized carrying out the information that digital form shows each input, output by LCD MODULE.
Shown in Fig. 3 E, in analog-to-digital conversion module, analog-to-digital conversion module receives the 0~5V voltage V by the outside input
Voltage, this voltage V
VoltageAt first behind a filter circuit filtering ripple, be connected on 2 ends of modulus conversion chip U2 through a resistance R 3, filter circuit is made up of diode D 1 and capacitor C 5 again, and diode D1 and capacitor C 5 are connected in parallel on voltage V
VoltageAnd digitally; 8 ends of modulus conversion chip U2,7 ends, 6 ends join with 47 ends, 49 ends, 48 ends of central processing unit U1 respectively, the 5 end ground connection of modulus conversion chip U2, the 1 termination 5V power supply of modulus conversion chip U2, the 3 termination 5V power supplys of modulus conversion chip U2, and 3 ends and digitally between be connected to another filter circuit, this filter circuit is made of capacitor C 6 and capacitor C 7, this capacitor C 6 and capacitor C 7 be connected in parallel on 3 ends and digitally between, 4 ends are through capacitor C 8 ground connection.
Shown in Fig. 3 F, in the utility model, D/A converter module includes analog-digital chip U3, voltage changes electric current chip U4 and 5V changes 24V power supply chip U6;
5V changes the 1 termination 5V voltage of 24V power supply chip U6,2 end ground connection, and 3 ends output 24V voltage, and join 4 end ground connection with 4 ends that voltage changes electric current chip U4.
The 1 termination 5V power supply of analog-digital chip U3,2 end ground connection, 3 ends, 4 ends, 5 ends join with 61 ends, 60 ends, 59 ends of central processing unit U1 respectively, and 1 end that 6 ends and voltage change electric current chip U4 joins.Being connected of three terminals on three terminals on the analog-digital chip U3 and the central processing unit U1, but realized D/A converter module receives changes electric current from the voltage supplied of central processing unit output voltage V
Out
Voltage changes the 2 end ground connection of electric current chip U4,5 end ground connection, 7 ends and 12 ends are connected (7 ends with 12 ends respectively with 1 end of electric current output interface J2 with 2 ends be connected) through electric current output interface J2 with using terminal as the output of electric current, and realization is with the stable electric current supply use terminal with 4~20mA.
Shown in Fig. 3 G, alarm output module at first receives from the high-low level signal PC5 of the 40 ends output of central processing unit U1, this height electricity signal PC5 frequently connects the 5V power supply after resistance R 34, and this high-low level signal PC5 is again through being connected to after the resistance R 35 on the base stage of triode Q9; The emitter of triode Q9 is connected on 2 ends of relay K 1, the grounded collector of triode Q9; Be parallel with diode D11 between 2 ends of relay K 1 and 1 end, and 1 termination 5V power supply, 3 ends of relay K 1,4 ends and 5 ends are as the switch of alarm signal output, and alarm signal output interface J6 can join with loudspeaker, realizes the broadcast of alarm sound.In the utility model, it is 8550 that triode Q9 chooses model, and it is TQ2-5V that relay K 1 is chosen model.
The supervising device of a kind of voltage input and current output of the present utility model can be with 0~5V analog voltage signal V
VoltageInput, and 4~20mA analog current signal I
Electric currentOutput, be common analog signal in the commercial Application now, solved stability and the required precision of using terminal that electric current is needed, thereby protected the use terminal effectively.