IE44656B1 - Electrical meter apparatus - Google Patents

Abstract

In this maximum-demand meter which consists of a kilowatt-hour meter and a maximum-demand mechanism, the maximum-demand mechanism is formed by a microcomputer with integrated memories. Information of the energy consumption by the kilowatt-hour meter is provided to the maximum-demand mechanism in the form of pulses. The microcomputer is controlled by external coding plugs and is customer-oriented in accordance with the requirements of the users. When the supply voltage drops below a certain value, a mains failure signal is also triggered which causes all data to be saved to be transferred into a non-volatile memory.

Description

'This invention relates to electrical meter apparatus, and is particularly concerned with an electrical maximumdemund energy meter apparatus.

An obstacle to the use of maximum-demand meters by small 5 consumers of electrical energy is the relatively high cost of conventional mechanical instruments, which involve a relatively large amount of labour in manufacture and adjustment For reducing this cost nnd thus providing an economical maximum-demand meter, electronic components are suitable, although long-time reliability and economical manufacture of an electronic maximum-demand meter tends to require a small number of components.

In electronic maximum-demand meters, a requirement exists that, on failure cf the main supply, the numerical value of ιό the highest maximum demand which has until then been reached during a measuring period iusually a month) mu3t remain stored, additionally, particular states of the control logic system must be stored in order to ensure that, upon restoration of the mains supply, the maximum-demand register will resumr 2θ from where it was interrupted. Thi3 is particularly important if the maximum-demand register has been interrupted by mains failure during a monthly transfer of a monthly maximum into η cumulative counter, in order to prevent the transfer of incorrect values, -cr the transfer of a number having, for -2example, a maximum for four digits (such aa 9999) from an electronic monthly store into a mechanical accumulative counter, periods of a few minutes may be involved in the case of stepping speeds of, for example, 10 to 20 Hz.

Therefore, it is Quite possible that any mains failure may interrupt a transfer operation.

Accoraing to the present invention, there is provided an electrical aaximum-uenand energy meter apparatus which comprises a digital microcomputer for receiving an input signal io represent tive of an energy demand and providing aa output signal representative of the maximum energy demand over a preceding predetermined measuring period, the microcomputer comprising a non-volatile score.

The provision of the micrccvmputer le^ds to the possibility of the apparatu? having a rel-civcly smali number of component parts. The provision of the non-volatile store enables essential data to bo stored during a power failure, as will be explained further in the following description, in ..hich various embodiments of the invention are described, by way of example.

Although non-volatile stores nay consist of any suitable logic circuitry for storing data for a given time in the absence of a power supply, electronic non-volatile stores available at the present state of the art of integrated circuit technology 25 tend to have the property that they may be written into only a limited number of times (for example 10° times). ->uch stores .- 44857 The process of this invention produces a safe and economical method and is readily adaptable to large scale batch or continuous production of perhexiline in yields greater than 90%. Moreover, when prepared in accordance with the preferred embodiments of the present invention, perhexiline may be obtained In high purity and in yields as high as 99.9%.

The catalyst which is used ln the process of 10 this invention is preferably prepared by azeotropically distilling a mixture containing a finelydivided, porous Raney nickel catalyst in cyclohexane, pentane, hexane, heptane, dioxane or tetrahydrofuran.

The mixture most preferably comprises cyclohexane.

An especially preferred process for the preparation oi 2-(2,2-dicyclohexylethyl)piperidine according to this invention comprises azeotropically distilling a mixture containing a finely-divided, porous Raney nickel catalyst in cyclohexane, thereby removing 2q substantially all traces of water from the catalyst, hydrogenating 2-(2,2-diphenylethenyl)pyridine in cyclohexane, using the catalyst thus obtained, at a hydrogen pressure of from 68 to 72 atmospheres and a temperature of from 200 to 210°C, until hydrogen uptake ceases, filtering off the catalyst to yield a clear filtrate, evaporating off the liquid from the filtrate, dissolving the residue thus obtained in a crystallisation solvent chosen from acetone, methyl ethyl ketone and alkanols having from one to 4 carbon atoms, adding a solution of maleic acid dissolved in said solvent, thereby precipitating 2-(2,2-dicyclohexylethyl); piperidine as its maleate, and recovering the pricipitate.

The starting material 2-(2,2-diphenylethsr.yl) pyridine is readily prepared by the condensation of a35 picoline and benzophenone in the presence of lithium amide to form a,a-diphenyl-2-pyridineethanol. Dehydration using phosphoric acid (85%), hydrobromic acid (48%) or hydrochloric acid may then follow, in order to prepare )4838 be provided separately from the rest of the microcomputer.

The maximum-demand energy meter apparatus is arranged to receive an in.ut signal to the microcomputer representative of on energy demand, which signal may coxorise, for example, rotor-disc pulse3 from an associated kilowatt-hour meter, which will typically be incorporated in the apparatus, 'i'he microcomputer may also be arranged to receive a reference frequency signal (for example, mains frequency) from which the measuring period for the maximum energy demand is calculated. For circulating the measuring period, the apparatus may comprise a time-base circuit which counts, for example, mains frequency pulses, .which then torn a measure of the duration of the measuring period, ond are applied to a comparison circuit, i’he microcomputer may air.o be arranged to receive information signals represents of , for example, tariff change-over orders, turn-on and turnoff orders, monthly reset orders, and power failure signals.

The microcomputer may be arranged to procecs energy consumption data on the basis of a plurality of maximum-demand tariffs, and tariff change-over orders and turn-on and turnoff orders may be combined in one information signal, to optimise use of the inputs to the microcomputer. monthly reset order may be fed to the microcomputer, or the microcomputer nay provide its own reset order after calculation of the measuring period, as indicated above. In carrying out an automatic resetting operation, the microcomputer may operate in the process of this invention is utilized as a finelydivided, porous material. The catalyst is initially prepared as a 50:50 alloy of nickel and aluminium utilizing a graphite crucible at a temperature of 1000°C.

The molten alloy is cooled, crushed to approximately 1/4 pieces in a jaw crusher and physically reduced to a finely-divided granular state in a ball mill equipped with 1/2 steel balls (200 mesh U.S. Sieve Series). A solution of 7-10% sodium hydroxide is added to partially leach the aluminium from the surface of these granules. The resulting catalyst contains approximately 90% nickel and 9% aluminium and has a total particle size distribution of approximately 25% in the zero to 20 micron range, 70% in the zero to 40 micron range, and 99% in the zero to 100 micron range. Alternatively, the actual preparation of these catalysts can be avoided if desired Inasmuch as they are readily available from commercial sources (Davison Chemical Division, W.R.

Grace and Company).

As previously indicated, it has been found necessary to remove all of the water from the Raney nickel catalyst in order ro achieve complete reduction of the 2-(2,2-diphenylethenyl)pyridine. Ordinarily, Raney nickel catalysts are prepared or supplied commercially as aqueous slurries. Raney nickel is highly polar and traces of water adhere tightly to it. Generally, the prepared catalyst is washed three or four times with approximately five or six volumes of anhydrous methanol per washing. The catalyst is then left standing overnight under an additional two volumes of anhydrous methanol. Allowing the multi-washed catalyst to stand overnight under the final anhydrous methanol wash improves its water removal, but does not achieve total water removal.

In order for the successful operation of the catalyst it has been found highly preferable to remove the final traces of water by azeotropic distillation. Solvents such as benzene, toluene, cyclohexane, pentane and heptane can be employed. Cyclohexane is the dehydration solvent of choice, inasmuch as it is also the 4 6 a 6 the whole program ic entered into the store ir. a testing station by a suitable data carrier (for example a punched tape), all the customer's wishes being simultaneously programmed. Secondly, the microcomputer may have a mask programmable program store together with an externul store which permits variation of at least parts of che microcomputer program, which permits customer-oriented programming of the microcomputer.

The external store may comprise, for example, a dioae or ..ire-bridge read-only store, 9nd may poszioly be in the form K, cf fixed program encoding plugs. Thirdly, where the program rest of the store of the microcomputer is separate from che^microcomputer, che whole program store muy be exchanged m dependence upon a customer's requirements.

Depending upon the number of maximum-demand tariffs, the microcomputer may provide a numaer of output signals representative of the monthly maximum energy demands, and also of the momentary energy demand. Keans may be provided for providing che output signal(s; in analog form, rather than in digital fora, und the output signal(s) may be used for driving visual display means. Additional control signals for resettable counters, cumulative counters and ether indicators may be deliverer in the case of multiple maximum-demand tariffs. rarticuiarly when the microcomputer is provided on a single chip, it may have a relatively small numoer of input pins, the use of which is prefe:usly optimised ey preceding multiplexing devices. Thus, the input of external orders to -7Another critical feature of this invention is the temperature at which the process of this invention is conducted. At temperatures of less than 160°c., no appreciable reduction to 2-(2,2-dicyclohexylethyl) piperidine occurs. Too high a temperature, on the other hand, results in a thermal degradation of the reaction mixture. Thus, the process of this invention is conducted within a temperature range of from 160 to 25O°C., and preferably at a temperature of about 200°C to 210°C. The particular choice of temperature selected is a function of both the hydrogen pressure and the reduction period. Thus, generally the higher the hydrogen pressure, the lower the required temperature for the reduction process, within the above limits.

In general, the process of this invention is conducted in a solvent as a batch-operated heterogeneous reduction. A slurry of the finely-divided, porous, anhydrous Raney nickel catalyst in a suitable solvent is added to an appropriate reactor or autoclave previously purged with nitrogen or sone other inert gas. Suitable solvents include those which are inert and in which 2-(2,2-diphenylethenyl) pyridine is at least slightly soluble. The 2-(2,2-diphenylethenyl) pyridine is dissolved or suspended in one of the aforementioned reduction solvents and added to the reaction vessel. After purging with nitrogen gas, hydrogen gas is introduced into the system to the desired pressure and the reactor is stirred and heated to its operating temperature. Hydrogenation is continued for approximately 3 to 5 hours or until further hydrogen uptake ceases. The reaction mixture is cooled and the catalyst removed by filtration, being careful to keep the catalyst continually wet and not exposed to air. The desired product can be recovered from the filtrate in accordance with well known procedures, as for example by extraction or via solvent removal techniques. <14 6 5 6 ·» 21» omitted for very economical naccimum-demand Deters; on return of tti power after a power failure, the microcomputer may start .-gain from a predetermined program point and ail the be stores Siiy/net to zero.

The microcomputer may readily be arranged to receive control pulses which are fed through the supply system from a central control, -and to process the control pulses to produce appropriate switching ordet'3 for the microcomputer, it is merely necessary for the control pulses to be filtered out of the supply system and to be presented to the microcorn puter in the form of satisfactory digital signals. Thus, decoding or the Control puls-s, which would otherwise be necessary, cor. te emitted. fhr meter sppar tus ts;· typically include display means for visually displaying c it pm. data from the microcomputer.

It is possible to employ -. single display which may be switched over to display cifferent data, and the display mean, may include an electrical digital display, an electrical analog display, or a mechanical display. i*'or a digital display, light-emitting uitdes , liquid crystals, ana the like may be employed, i’er .an electrical analog display, conventional pointer instruments may be used, and in appropriate such cases, it may be economical fcr the current for r.nese instruments to be derived directly from the computer without any digital-to-snalog converter, such th-.t the instruments, are driv-.-n directly with a pulse-codv-modulate.. signal, cf any desired frequency, from the microcomputer. - 4 4 057 at the catalyst surface. The product which is continuously formed is collected and removed from the bottom of the catalyst bed. In addition to providing for continuous operation, such a system has the advantage of eliminating the necessity of separating the catalyst from the reaction product at the completion of the reaction. Multiple feed passes and recyclizations can be easily installed to increase the efficiency of the reduction.

Simplicity and reduced production costs make,this method highly desirable for large-scale commercial operation.

The following Examples illustrate the invention while the following Preparations illustrate how suitable starting materials may be made.

Preparation I^a,a.-Dlphenyl-2-Pyridine-ethanol Benzophenone, 32.4 kq (177.8 mole) a -picoline, 33.1 kg (355.5 moles), and lithium amide 4.54 kg (197.4 moles) are charged into a 30 gallon reactor arranged for reflux operation. The mixture is stirred, rapidly heated to 125°C. and maintained at this temperature. The rate of ammonia evolution gradually increases and after about 3 to 4 hours of reaction time only occasional heating is required to maintain the desired temperature and a rapid evolution of ammonia After about 5 hours, a vigorous surge of ammonia evolution is noted. Following the ammonia surge, external heating is continued and the reaction maintained at 125°C. for an additional 6 to 8 hours. The reaction mixture is cooled to 7O-8O°C. and rapidly added to approximately 230 liters of water at 25°C. Stirring is continued for approximately 30 minutes and the solid removed by filtration. The filter cake is thoroughly washed with water and dried at 6O-7O°C yielding 42-6 kg of a,a-diphenyl-2-pyridineethanol having a m.p. of 147-51°C. 63 6 κ· variation of at least parts of the microcomputer program.

. An apparatus according to ;\ηγ preceding claim, wherein the microcomputer is arranged to receive power-failure signal in the event oi a power failure, upon receipt of which signal the microcomputer is operative to transfer volatile data in the ::.icrocompucer into tne r.cn-volatile store; befo:»the collapse· of the . up. ly voltage, the micror.om- .ter tc.../ operative to restart upon Tester;·.tion of power cy .'si-.ttp wut data from the non-volatile store for further tree-3-.irr. 11. An apparatus a. ording to il.dn '0, who em tn.-.· micruco .....te. is arr ngeu to restart always at ·' nr .ale terc.ir.ec program point. 12. An apparatus ae-ordr.r to claim cr 1‘, including meins for detecting power failure mu supplying sai a power- f.. ilur·sign.-l. 13. Au apparatus according to any preoeai:·;· cl.;c ., wherein the non-vol.*tile store is .arranged to store curio:;: r-arientu„ programming of the microcomputer . 14. Ar. apparatus according co any or.e of claims 1 to 5, or to any one of claims 7 to 12 as appendant thereto, wherein the mi-rocomputer inducer, .in external reau-only store for custoueroriented pjogranming of the microcomputer.

· An apparatus according to any preceding ciaim, wherein the microcoa. uter is arranged co receive a reference fre-.ruency signal and calculate therefrom said measurin' period.

Claims (1)

1. 6. An Mppumiuy uccording to any preceding, claim, wherein tho microcomputer is arranged to carry out an automati c resetting operation and to calculate from said reference frequency signal tho duration of a resetting period. 1?. An apparatus according to any preceding claim, wherein the microcomputer is arranged to receive control pulses and to process the control pulses to produce switching orders for the microcomputer. 10. An apparatus according to any preceding claim, wherein the microcomputer is arranged to process energy consumption data on the basis of a plurality of muxiauo-de.and tariffs. 19· An apparatus 'according to any preceding claim, including display means for visually displaying output data from the microcomputer. £C. i.n apparatus according to claim 19, wherein said display means includes an electricul uigi-.al display. 21. ;»n apparatus according to claim 19 or 20, wherein said display means includes an electrical analog display. 22. An apparatus according to claim 21, wherein said analog display is arranged to be driven directly with a pulse-codemodulated signal from the microcomputer. 23. An apparatus according to claim 19, wherein suid display means includes a mechanical display. 24. An apparatus in accordance with claim 1 and substantially as hereinbefore described.