CN100451905C

CN100451905C - Programmable controller for temperature and humidity

Info

Publication number: CN100451905C
Application number: CNB2007100707440A
Authority: CN
Inventors: 贺惠农; 秦熠; 周建川
Original assignee: HANGZHOU VICON TECHNOLOGY Co Ltd
Current assignee: HANGZHOU VICON TECHNOLOGY Co Ltd
Priority date: 2007-08-10
Filing date: 2007-08-10
Publication date: 2009-01-14
Anticipated expiration: 2027-08-10
Also published as: CN101109968A

Abstract

The utility model discloses a programmable atmospheric controller. The ARM processor is respectively connected with an A/D modular converter, a USB interface module, a serial port communication uart port, an internet web opening, a LCD display/touch screen interface module and an I/O. The external moisture transmitter is connected with the end where the current is changed into the volt circuit, while the other end id communicated with the high precision A/D modular converter. The CPLD programmable logic module is connected to the voltage via the D/A module so as to be changed into the current circuit. The voltage is changed to the current circuit which is communicated with the outboard record instrument and the peripheral control unit. For the atmospheric controller, the temperature measuring accuracy reaches 0.01 and the accuracy for the measure of humidity reaches 0.1, so that short control cycle, good control result and usableness are achieved. The network connection realizes the PC remote control.

Description

Programmable controller for temperature and humidity

Technical field

The present invention relates to a kind of programmable controller for temperature and humidity.

Background technology

Environmental test is one can make the value-added process of product, more and more is subject to people's attention.And humiture type environmental test is as basis a kind of the most in the environmental test, and utilization field and has extensively been improved the environmental suitability and the reliability of the dual-use product of China greatly, and directly caused the quality of product to promote.The humiture testing equipment generally is made up of operating room, conditioning equipment, utility appliance, control system.Control system is determining the automation process of whole device, and control system comprises temperature and humidity controller, program set station, safety alarm device etc.

Summary of the invention

The object of the present invention is to provide a kind of programmable controller for temperature and humidity.At the above-mentioned background technology, on the basis of traditional temperature and humidity controller technology, use up-to-date embedded technology, increased multiple function.Jumbo memory headroom; Adopt novel colored touch screen to make man-machine interface more friendly; USB interface and network connecting function have been introduced.

The technical solution used in the present invention is:

Comprise that current conversion is a potential circuit, high-precision A/D modular converter, arm processor, CPLD programmed logical module, D/A modular converter, voltage transitions are current circuit, usb interface module, serial communication uart interface, Internet web network interface, LCD demonstration/touch screen interface module and I/O mouth; Arm processor respectively with high-precision A/D modular converter, CPLD programmed logical module, usb interface module, serial communication uart interface, Internet web network interface, LCD demonstration/touch screen interface module is connected with the I/O mouth; Current conversion is that an end of potential circuit is connected with high-precision A/D modular converter, and the other end links to each other with outside humidity transmitter; It is current circuit that the CPLD programmed logical module connects voltage transitions through the D/A module, and voltage transitions is that current circuit links to each other with external record instrument, peripheral control unit.

The beneficial effect that the present invention has is:

1) the controllable temperature scope is :-99 ℃-150 ℃, the controlled humidity scope is 0-100%RH; 32 ARM embedded technologys and high-precision A/D chip, temperature measurement accuracy reaches 0.01, and the moisture measurement precision reaches 0.1; Control cycle is short, controls effective.

2) man-machine interface LCD demonstration/touch-screen has adopted the TFT color screen, and operating display frame is divided into five major parts: operation, operation picture, definite value are set, program setting, and picture close friend attractive in appearance is easy to operate.

3) US B interface functional device has made things convenient for the renewal of internal control program.

4) realization of network connecting function makes far distance controlled more effective.

Description of drawings

Fig. 1 is the circuit block diagram of the temperature and humidity controller among the present invention.

Fig. 2 is that 4～20mA current conversion is a potential circuit among the present invention.

Fig. 3 is an A/D circuit module among the present invention.

Fig. 4 is a D/A circuit module among the present invention.

Fig. 5 is that 4～20mA voltage transitions is a current circuit among the present invention.

Fig. 6 is a LCD demonstration/touch screen interface module of the present invention.

Among the figure: 1, current conversion is a potential circuit, 2, high-precision A/D modular converter, 3, arm processor, 4, the CPLD programmed logical module, 5, the D/A module, 6, voltage transitions is a current circuit, 7, usb interface module, 8, serial communication UART interface, 9, Internet Web network interface, 10, LCD demonstration/touch screen interface module, 11, the I/O mouth.

Embodiment

The invention will be further described below in conjunction with drawings and Examples.

As shown in Figure 1, the present invention includes 4～20mA current conversion is potential circuit 1, high-precision A/D modular converter 2, arm processor 3, CPLD programmed logical module 4, D/A

modular converter

5,4～20mA voltage transitions is a current circuit 6, usb interface module 7, serial communication uart interface 8, internet web network interface 9, LCD demonstration/touch screen interface module 10 and I/O mouth 11; Arm processor 3 respectively with high-precision A/D modular converter 2, CPLD programmed logical module 4, usb interface module 7, serial communication uart interface 8, Internet web network interface 9, LCD demonstration/touch screen interface module 10 is connected with I/O mouth 11; Voltage transitions is that an end of current circuit 1 is connected with high-precision A/D modular converter 2, and the other end links to each other with outside platinum resistance; It is potential circuit 6 that CPLD programmed logical module 4 connects current conversion through D/A module 5, and current conversion is that potential circuit 6 links to each other with outside relay.

As shown in Figure 5, described voltage transitions is that current circuit 6 is made up of XTR111 chip and peripheral circuit thereof, has four tunnel 4～20mA output, and two-way is as record, and two-way is as control.

As shown in Figure 3, described high-precision A/D modular converter 2, this module is made up of ADS1216 chip and peripheral circuit thereof, input end links to each other with platinum resistance, the ADS1216 chip produces the two-way steady current, the voltage that produces of linking to each other with outside platinum resistance connects 3,4 pins of ADS1216 chip, and the discrete signal of conversion back output is connected to ARM by pin DIN, DOUT.

As shown in Figure 4, described D/A modular converter 5 is made up of the AD5326 chip of 24 high accuracy number/analog-converted, and digital signal is imported through the SDA of chip pin from the CPLD programmed logical module; Clock signal is imported from the SCL pin; The input that A0 pin and A1 pin two ends are set can select a road among four tunnel output VoutA, VoutB, VoutC, the VoutD to be connected to the input end that voltage transitions is a current circuit 6 as output signal.

As shown in Figure 2, described current conversion is a potential circuit 1, and input is connected with the D/A circuit module, and the operational amplifier anode is the input of 4～20mA electric current in this circuit, negative terminal is linked to each other by the parallel circuit of the feedback resistance R129 of resistance R 83 output terminals, and output terminal links to each other with outside relay.

As shown in Figure 6, described LCD demonstration/touch screen interface module 10 directly links to each other with arm processor, and through LCD demonstration/touch screen interface resume module, magnitude of voltage is become by 3.3V and is 5v, thereby drives LCD/ touch-screen operate as normal.

Main interface is arranged described usb interface module and from two interfaces, main interface is realized the read-write capability of u dish, is used to the programming of the program that realizes from interface; Network connects has realized the Long-distance Control of computing machine to controller.

When the measurement with wet hygrometric is spent, dry-bulb temperature and wet-bulb temperature have been converted to analog voltage signal through sensing circuit, if through outside humidity transmitter hygrometric degree, 4～20mA current signal that outside humidity transmitter produces produces analog voltage signal through electric current to voltage conversion circuit, analog voltage signal is converted to digital voltage signal through A/D, digital voltage signal is input to arm processor, signal through the ARM processes and displays to LCD, when look-at-me was imported on the touch-screen, arm processor drove corresponding relay work through SN74ALVC164245I/O chip or efficient D/A treatment channel output real-time control signal to external terminal.

Above-mentioned embodiment is used for the present invention that explains, rather than limits the invention, and in the protection domain of spirit of the present invention and claim, any modification and change to the present invention makes all fall into protection scope of the present invention.

Claims

1, a kind of programmable controller for temperature and humidity, it is characterized in that: comprise that current conversion is potential circuit (1), high-precision A/D modular converter (2), arm processor (3), CPLD programmed logical module (4), D/A modular converter (5), voltage transitions is current circuit (6), usb interface module (7), serial communication uart interface (8), Internet web network interface (9), LCD demonstration/touch screen interface module (10) and I/O mouth (11); ARM microprocessor (3) respectively with high-precision A/D modular converter (2), CPLD programmed logical module (4), usb interface module (7), serial communication uart interface (8), Internet web network interface (9), LCD demonstration/touch screen interface module (10) is connected with I/O (11); Current conversion is that an end of potential circuit is connected with outside humidity transmitter, and the other end links to each other with high-precision A/D modular converter; It is current circuit (6) that CPLD programmed logical module (4) connects voltage transitions through D/A module (5), and voltage transitions is that current circuit (6) links to each other with external record instrument, peripheral control unit.

2, a kind of programmable controller for temperature and humidity according to claim 1, it is characterized in that: described current conversion is potential circuit (1), input is connected with outside humidity transmitter, the operational amplifier anode is the input of 4～20mA electric current in this circuit, negative terminal is linked to each other by the parallel circuit of the feedback resistance R129 of resistance R 83 output terminals, and output terminal links to each other with the A/D circuit module.

3, a kind of programmable controller for temperature and humidity according to claim 1, it is characterized in that: described high-precision A/D modular converter (2), this module is made up of ADS1216 chip and peripheral circuit thereof, input end links to each other with platinum resistance, the ADS1216 chip produces the two-way steady current, the voltage that produces of linking to each other with outside platinum resistance connects 3,4 pins of ADS1216 chip, and the discrete signal of conversion back output is connected to ARM by pin DIN, DOUT.

4, a kind of programmable controller for temperature and humidity according to claim 1, it is characterized in that: described D/A modular converter (5) is made up of the AD5326 chip of 24 high accuracy number/analog-converted, and digital signal is imported through the SDA of chip pin from the CPLD programmed logical module; Clock signal is imported from the SCL pin; The input that A0 pin and A1 pin two ends are set can select a road among four tunnel output VoutA, VoutB, VoutC, the VoutD to be connected to the input end that voltage transitions is current circuit (6) as output signal.

5, a kind of programmable controller for temperature and humidity according to claim 1, it is characterized in that: described voltage transitions is that current circuit (6) is made up of XTR111 chip and peripheral circuit thereof, have four tunnel 4～20mA output, two-way is as record, and two-way is as control.

6, a kind of programmable controller for temperature and humidity according to claim 1, it is characterized in that: LCD demonstration/touch screen interface module (10) directly links to each other with arm processor, through LCD demonstration/touch screen interface resume module, magnitude of voltage is become by 3.3V and is 5V, thereby drives LCD/ touch-screen operate as normal.

7, a kind of programmable controller for temperature and humidity according to claim 1 is characterized in that: main interface is arranged described usb interface module and from two interfaces, main interface is realized the read-write capability of u dish, is used to the programming of the program that realizes from interface; Network connects has realized the Long-distance Control of computing machine to controller.