Prepayment Electric Energy Meter with Multi-functional for Multi-user based on STC11F52XE Sun Wei 1,a and Tuo Jianzhi 1,b

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1 pplied Mechanics and Materials Online: ISSN: , Vol. 367, pp doi: / Trans Tech Publications, Switzerland Prepayment Electric Energy Meter with Multi-functional for Multi-user based on ST11F52XE Sun Wei 1,a and Tuo Jianzhi 1,b 1 Weifang Engineering Vocational ollege, Weifang ity, Shandong Province, hina a sun197@163.com, b tuojianzhi@163.com Keywords: electric energy meter; Multi-user; multi-functional; S5460; prepayment bstract. ased on the application of the single-phase electric energy meter, selected the ST11F52XE microcontroller of ST micro technology company and energy measurement chip S5460 of irrus Logic as the controller, sampled the user's voltage and current by time-sharing sampling with the multi-channel analog switch, controlling the ON/OFF of the electric energy of multi-user with the bidirectional holding magnetic relay, design a prepayment electric energy meter with multi-functional for Multi-user based on GPRS communication technology. This meter achieves the electric energy meter standard with one-level. Introduction For a long time, electric energy meter is used to measure the electric energy in our daily life, especially in single-phase energy meter, the traditional method, one meter for one user, periodically checking meter, has been a serious impediment to the development of convenient management mode with remote control and integrated management. ccording to the application of the electric supply and the problems exposed in the residential areas, office buildings and other multi-user spaces, developed a widely used single-phase intelligent electric energy meter measures the electric energy accurately, checks the meter remotely in real-time and manages conveniently[1,2]. The functional block diagram of the meter system is shown in Fig.1. Fig1. The functional block diagram of the meter system This system includes controller, storage unit, detection and sampling unit, display unit, power ON/OFF unit, the communication unit and other components. ll rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, (I: , Pennsylvania State University, University Park, US-13/05/16,01:40:46)

2 212 Mechanics, Simulation and ontrol III ontroller and storage unit ccording to the functional requirements of the system, takes the up-to-date multi-function microcontroller ST11F52XE as the system controller. The MU integrates 52K Flash program memory can store sufficiently complex control program, 1280 static RM and 9K internal EEPROM can sufficiently store the detection parameters of energy meter, retains its contents when the power is off, has 40 general-purpose parallel ports to facilitate communication with other functional chips. The chip uses QFP44 package with capacity of resisting disturbance and rich on-chip resources, minimizes the volume of the control system, easy to achieve integration. etection and Sampling Unit etection ircuit Unit. Using the isolating input method with transformer, converts the voltage and current to be the right information of the SM system. The sample of voltage uses a current transformer with the turn ratio of 1:1. The input voltage Ui is converted to the current in the primary circuit, as shown in Fig.2. The sample of current uses current transformer with proportion of 10 (50) /10 m, proportionally convers the users current to the current on the secondary side, then turns them to the weak voltage signal that S5460 can receive through a certain value resistors. s shown in Fig.3. T2 R6 R7 1K R8 GN Voltage Transformer 1K R VIS+ T3 Fig.2 Voltage transformer R12 R11 1K R VIN- IIN- 8 1K urrent Transformer R GN K 470 IIN+ R14 Fig.3 urrent transformer ll users are assigned to,, three-phase averagely, the voltage signal U, U, U that are detected by the voltage sampling circuit is applied to the S5460 by time-sharing sampling, the 4052 is controlled by the two address lines(p2.2 and P2.1). The users current is transformed into the voltage signal for S5460, The 4051 is controlled by the ST-MU through the P2.3-P2.7, many time-sharing detection current signals is applied to current signal input channel of S5460. The circuit schematic is shown in Figure 4. It needs to be noted that every voltage and current signals must be added synchronously, therefore, 4051 and 4052 address control signal must be executed synchronously.

3 pplied Mechanics and Materials Vol GN Y1 P2.7 P2.5 P2.4 P2.3 P0.0 P0.1 P0.2 P2.2 P2.1 S IN SLK OUT GN XIN XOUT S5460 IIN+ IIN- VIS+ VIN- IIN- GN P2.6 GN U1 INH VSS VEE V O/I 4051 U2 INH VSS VEE V O/I I/O7 I/O6 I/O5 I/O4 I/O3 I/O2 I/O1 I/O0 I/O7 I/O6 I/O5 I/O4 I/O3 I/O2 I/O1 I/O0 IIN15+ IIN14+ IIN13+ IIN12+ IIN11+ IIN10+ IIN9+ IIN8+ IIN7+ IIN6+ IIN5+ IIN4+ IIN3+ IIN2+ IIN1+ IIN0+ V U3 OUT/IN OUT/IN V O/I U+ U- U+ U- U+ U Fig.4 etective circuit of multi-users voltage and current Power measurement. Power / energy measured through the electricity metering I chip S5460 that launched by irrus Logic Inc., the chip has strong communication skills, high / low pass digital filter unit, serial interface, with highly integrated Σ / analog-to-digital converter (), two Σ/, high-speed power calculation and a serial communication interface integrated on a single chip, single-phase two-way power, energy metering function, and is applicable to a variety of automated measurement and remote control chip. The small-signal of voltage and current detected by S5460, are transformed to instantaneous numeric values by the on-chip, such values are taken into the on-chip power calculator after the digital filtering to measure the instantaneous current, instantaneous voltage, instantaneous power, effective value of the current, voltage and power, accomplish energy metering, digital - frequency converter, register, watchdog timer etc.. The chip generates the pulse in proportion to power by the energy 0 pulse conversion circuit, connects to the MU via the serial control interface, and delivers the detected data of the corresponding registers to the microcontroller. The P0 port of the MU is connected to the S5460 data input IN, output OUT signal clock SLK port connection, reads and writes the data from and to S5460. The program is shown as follows: WR_YTE: MOV R2, #08H INYTEl: LR SLK RL MOV IN, JNZ R2, INYTEl RET R_YTE: MOV R2, #03H OUTYTE: MOV R3, #08H OUTYTE2:SET SLK LR SLK MOV, OUT RL

4 214 Mechanics, Simulation and ontrol III JNZ R3, OUTYTE2 IN R1 JNZ R2, OUTYTE1 LR IN LR OUT LR SLK RET The design uses simple structure, high device utilization rate, is easy to automatically read meter. It is able to meet the requirements of measuring accuracy which load is relatively stable. Power ON/OFF and driver unit When the remaining power is zero, the meter automatically cut off the power by magnetic latching relays. The meter relay automatically closed the power supply circuit after pre-paying the power. This unit includes an interface and a driver. The interface circuit consists of the MU I/O interface, digital logic chip 74H138 and, shown in Figure 5. Upper address control signal by the 74H138 via the decoding method is used to control four. P1.3 P1.4 P1.5 P1.0 P1.1 P1.2 /Y0 /Y1 /Y2 /Y3 74LS138 Fig.5 The interface of Power ON/OFF circuit The driver circuit consists of the and PNP transistors and other component. The principles of the driver circuit is shown in Figure 6. JMX-94F is the relay with two-way magnetic latching. /Y0 /Y3 /Y00 /Y07 /Y10 /Y17 /Y20 /Y27 /Y30 /Y37 JMX0 JMX15 Fig.6 The driver of Power ON/OFF circuit

5 pplied Mechanics and Materials Vol One is used to control four relay at most, by controlling the value of based on the truth table of. isplay and communication interface circuits The display uses the L1602 with two-line information, the first line shows the current balance of power, and the second line shows the total value of the used power. The meter connects with the GPRS wireless terminal communication through RS-485 half-duplex communication mode, the transmit/receive control state controlled by the E and RE of 75L184. significant advantage of 75L184 chip is the on-chip, pin that is connected to a high-energy protection device for the transient interference, can significantly improve the reliability. In order to avoid the interference to the internal system from the noise of external communication line or high voltage uses the high-speed opto-coupler to isolate the SM system and communication network. Wireless terminal device receives the data collected in the field and transmits via the hina Mobile SMS/GPRS public network to the monitoring center, the monitoring center sends the processed data and remote control command to the wireless terminal, the wireless terminal device receives such information and perform them. ata transfer baud rate is in the bit/S, data transmission is transparent, TP/IP protocol is automatically converted, the user's meter do not need any hardware and software changes. Power supply uses 7-4V with lower power consumption. The wireless communication interface program is installed in the master server to automatically drive the underlying network port, accomplishes the communication with the remote wireless terminal, the data transmission can be bidirectional. The underlying communication data is formatted user-friendly according to the needs of users. The program self-adapts the communication requirements of the client application program according to the user software interface definition. onclusions ased on the ST11F52XE MU and the power/energy measurement chip S5460, designed a multi-user and multi-function prepayment meter with unique voltage and current detection circuit. Used the typical energy measurement method to design the control program, debugged the hardware and software of the power meter, and completed the development of multi-user and multi-function pre-payment meter. References [1] FNG Jun. The feature and principle of single phrase electronics energy meter[j]. Yunnan Electric Power, 2003, 31(1): [2] ZHU Tong, HEN Mao. The development and application of multi-user smart energy meter[j]. Journal of hongqing ollege of Posts and Telecommunications, 2001(6): [3] WU Lei. The design of smart electric energy meter based on the controller of T8952[J]. Journal of hang jiang University: Natural Science, 2008, 5(4): [4] LI Jianwei.S5460 in the application of electronic watt-hour meter[j].electronic Technology, 2003(6): [5] WNG Wenjiang. Thought and application about the code-decimal decoder of [J].Journal of Qian nan Nor-mal University for Nationalities, 2007(6):53-55.

6 Mechanics, Simulation and ontrol III / Prepayment Electric Energy Meter with Multi-Functional for Multi-User ased on ST11F52XE /

The Design of Wireless Data Collector based on WIA-PA Ligang Li 1,2,a, Zhongfeng Wang 1,2,b, Jianlong Huang 1,2,c

Advanced Materials Research Online: 04-06-5 ISSN: 66-8985, Vols. 97-97, pp 79-794 doi:0.408/www.scientific.net/amr.97-97.79 04 Trans Tech Publications, Switzerland The Design of Wireless Data Collector