Development of a single phase prepaid Electrical Energy Meter using 89S8252 microcontroller architecture
The Electricity Company implements the `Prepaid Electrical Energy Meter (PEM)' scheme among the electricity consumers to meet the objectives of: (i) collecting advance money and (ii) motivating the customers to make conservative use of electricity. The 2nd objective can be effectively achieved with an indoor type PEM fitted with 7-segment bright display unit. The meter designer aims, using appropriate hardware modules and software routines, to guide the PEM for cycling through the following steps: (i) deduct cost of every 0.01kwhr energy consumed, (ii) display balance, (iii) check balance, (iv) disconnect load at zero balance, (v) issue alarm signal to engage correct prepaid card, (vi) read the prepaid card, (vii) zeroing the prepaid card, (viii) update balance, (ix) save balance in nonvolatile EEPROM at power failure, and (x) retrieve balance from EEPROM at power resumption. This paper has described, based on extensive experiments on real hardware using AT89S8252-ADE7755-AT90S2313 chip set, the implementation methodology of a PEM with bright display unit. A prototype meter has been built, tested and found to work as per standard specifications.
Prepaid energy meters network via power system communication
This paper presents a new idea of designing a prepaid energy meters that has the ability of being connected to a unified centre (Energy Company). The process of connecting the meters to a unified centre can facilitate the security, control and maintenance purposes. The mentioned network is economical because it is established using the existing power lines instead of constructing a new wired or wireless network. The data are transmitted over this network using Power Line Communication (PLC) technology. A special device is used to inject the data to the network and captures them from the network; this device is the power line communication modem. A simple design of the network is done using two computers and two modems (PLM) plus a program code. By using a modem the program can take the measured data from the meter then send them to the computer server and vice versa. The designed network makes the energy company able to access any prepaid energy meter in the unified area and control the measurements of this meter; and as a result, stealing of electricity can be prevented. Also company can communicate with the consumer by sending text messages such as a serial number for recharging the energy or alarm the consumer before the whole amount of electricity is totally consumed. Moreover, this network offers the ability of controlling the supply of energy such as switch “On” or “Off” of the electricity supply.
Studies on the composition, quality and processing of triticale. Part II. Mineral composition of grain and flour.
Mineral composition of grain and flour in 14 promising triticale strains from India are reported. The mean values for whole grain, i.e. Ca (0.47 mg/g), P (2.70 mg/g), K 4.60 mg/g, Na (352 micrograms/g), Zn (41.6 micrograms/g), Cu (7.0 micrograms/g), Fe (73.4 micrograms/g) and Mn (33.6 micrograms/g) were obtained as compared to those of flour, i.e. Ca (0.27 mg/g), P (0.97 mg/g), K (1.64 mg/g), Na (231 micrograms/g), Zn (26 micrograms/g), Cu (4.0 micrograms/g) and Mn (10.5 micrograms/g), respectively. These values were found to be considerably higher than those of wheat. Highly significant positive correlations of ash with sodium and zinc in whole grain were observed. In the case of triticale flour, highly significant positive correlations of ash with manganese, phosphorus and potassium were obtained.