【 Weak current College 】 PLC in teaching building lighting control system 】

Summaries of articles from schools economizing energy point of view, the introduction of a PLC in a classroom building classroom lighting control system that focuses on a timetable on classroom lighting for reasonable supply methods, timetable of digital processing and lighting control program design.
Keywords PLC classroom digital lighting control-table 1 problem
Universities in teaching process consumes a considerable amount of energy, such as classroom lighting, experimental, practice and research is required to power support. According to statistics a College, teaching the power consumption can be accounted to the school's total electricity consumption of 50 per cent yearly tariff of up to 100 million. The survey found that, in the teaching process, the energy wasted in the classroom "very serious", "and classroom lights and more rarely, daytime light intensity does not turn off the lights and other phenomena, this is undoubtedly the ubiquitous wasted energy, increased teaching costs, increased expenditures for the Academy. The author is located in the college classroom 146 rooms in total, each classroom is equipped with 12 or 16 lamp 40W light bulbs are used for lighting. Because of this waste, college expenses at an annual rate of more than 20 million of electricity. The author for the classroom is a serious shortage of electricity, the lighting system of teaching building for technical transformation programme, on the classroom lighting electricity implement intelligent management, enabling classroom lighting reasonable and effective.
The lighting intelligent control device application of PLC control technology

Be introduced.
2 classroom lighting control strategy
In order to ensure that the teaching in the classroom during the class, for electricity should be reasonable arrangements for classroom lighting, strict control of non-teaching of electricity, the effective use of Institute resources. Advice on classroom lighting electricity implement the following strategies:
(1) a school building as a unit to the classroom to control objects, each PLC control a teaching building.
(2) every classroom press curriculum implementation. In order to improve the effectiveness of supply, the simplified procedure of design and debugging, troubleshooting, should carry out level control PLC.
(3) in order to compensate for the PLC cannot under natural light intensity within the classroom to automatically adjust the supply policy, should be in the PLC input access-electronic control unit. When the natural light meets the lighting requirements, to provide signal systems PLC will refuse to teaching building power supply.
(4) in order to make rational use of resources, and give full play to the efficiency of use of the library, homework sessions should focus to a classroom building power supply.
Will be scattered in various teaching building of one of the few students within the classroom into a building or the library, the rest of the building does not provide lighting.
Choice of 3 PLC
Teaching building lighting intelligent control process is more complex, its characteristics are PLC input signal is far less than the output signal. From an economic point of view, select FX2N-16M plus FX2N-16EYR expansion module, this module of the actual use of the number with the number of classroom teaching building.
4 PLC control program design
Teaching building lighting intelligent control system of control by week calendar map program and class period selector, class time digital programs, classroom lighting control, etc.
(1) week calendar and day time program. Each week, the classroom curriculum based timetable. A classroom curriculum schedule is scheduled to perform, the classroom situation is of course depends on two factors: one is the weekly calendar, date time schedule belonging. From a teaching perspective, the two periods of validity are Monday to Friday, and the day schedule in several periods of class. Both effective and relevant curriculum schedule settings. Therefore, to supply power to the classroom, curriculum effectively becomes the blueprint for lighting control procedures prepared. Since the day of the week calendar and timetable is a periodic cycle, the cycle is associated with a different and, therefore, when writing a program, the difference must be fully taken into account. Figure 1-week calendar mapping program and class time selector.
Figure 1, X0, X2 as clock input contacts, X1, manually enter contacts for X3, M31 ~ M37-week calendar map contacts. If closed the M31 contact mapping week date is Monday, Y20, Y21 ... Y26 for week date display.
Because of the school day timetable 27 times, each time with different content of work and rest. The 27 time period covering the time period is in class at 8: 10-11: 55, 14: 30-18: 40, 19: 30 ~ 21: 10. A total of 10 lesson periods. Program design, must be entered in the clock signal to 10 hours of signal, shown in Figure 1, M6, M8 and M10, M12... M25 corresponding clock control device output signal of the image class, enter the contact's schedule signal signal select class. In order to facilitate staff regulation after power outage, confirm that the adjustment is correct, the program set up manually adjust button and lessons at Y0, Y2, Y3, Y4, Y5... Y11.
Since week calendar and daily routine is run periodically, order cycle time with irreversibility, and both cycle. According to this characteristic, the use the shift method design week calendar mapping program and class hours of a selector is used to enter clock control signal (X0, X2) for shift drive signals.
(2) classroom curriculum schedule of digital processing. A classroom is a window class, the classroom day determined timetable. In order to achieve the classroom lighting control performed by day timetable, there are no lessons course power supply, power control logic, it must be every classroom in a class period there are courses and courses between digital correspondence means that the operation by the program, into the classroom lighting control signal. In order to make full use of internal resources PLC, processing method is to take the layered coding, digital representation. For example, a school building has six layers, each layer has 8 classrooms. If the first section in addition to the 3 remaining outside of the classroom are a lesson, coding, a class is expressed as "1", no classes are represented as "0", "sixth K61" represents a layer in the morning of the first class of the corresponding data. Its digital processing as shown in Figure 2.
For the convenience of digital input, use the decimal notation: K61 = 261For this layer should be time digital classroom curriculum schedule. According to the above method, you can find this teaching building layers of digital timetable.
(3) classroom lighting control program. The date determined by the program and driver links, class signal and digital transmission links, the link with the reset signal class, lighting control links and other main components. Figure 3 represents a teaching building Monday morning hours of lighting control program.
Program, M31 to corresponding week date contact. M31 contact closed, so that the program enters the digital electronic timetable. M6, M10 for class signal contact. When the morning of the first (or second) course class time to, M6 (or M10) contact closure, the transfer instruction MOV the teaching building of digital timetable into data register D1-D6. At the same time, M41 (or M42) closed, D1 (or D2) digital processing by K2Y30 (or K2Y40) output, complete the lessons in the classroom lighting power supply. Figure 3 M9, M13-class power contacts. When the first (or second) class in the class time to, M9 (or M13) contact closed, ZRST drive D1-D6, Y30-Y80, M41 (or M42) reset, disconnect the classroom lighting power supply line.
To make the program work with date and day of week timetable, thelighting control program can be divided into five pieces, each with the master directive MC\MCR segmentation and week date and day of the school timetable.
5. concluding remarks
PLC in lighting intelligent control unit, the classroom programme according to the timetable powered, classroom lighting power supply enables automatic control, rely on manual operation of the passive situation, keep the classroom electric waste problems to solve.
Because the control program design structured, when classroom curriculum schedule changes, the program of adjustment easy to make, without changing the program's overall structure. At the same time, the application of PLC for architectural lighting using network control. ■
Reference documents
1 King zhaoyi the small programmable controller utility technology "[M]-mechanical industry press, 2004
2 Zhao books-Ling. temperature all the year round. Zhu kin-mo. Wang Xiaoyan. Cone Crusher of fuzzy control system design apery [J]. the micro-computer and information law 2005