JPH0310278B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement of a road survey system that collects timed data stored in a plurality of terminal devices.

[Technical background of the invention]

A road survey system is widely known as a system for investigating the amount of electricity, gas, water, etc. used within a predetermined period of time. This collects time-limited data (for example, power usage) for each terminal device for a large number of terminal devices (also called road survey devices).
Conventionally, these terminal devices have a power conversion circuit that converts the load power into a number of pulses proportional to the usage amount, a counting circuit that counts the output pulses of this power conversion circuit, and a It consists of a memory that stores the counted value of , an output control circuit that outputs the contents of this memory to the outside, and a clock circuit that ticks the time.

Time-limited data from these terminal devices is collected by data collection personnel who visit each terminal device at regular intervals (for example, once every two months) by connecting a portable cassette recorder that is separate from the terminal device. do. The collected data is processed by a computer and used for an electric power load survey.

By the way, each of the above-mentioned terminal devices has a built-in clock circuit, but these clock circuits are often affected by temperature, electric power, etc. and the time becomes incorrect. There is a problem that cannot be grasped accurately. Therefore, when collecting data, the collecting staff supplies current time data from the cassette recorder to the terminal device and adjusts the time.

[Problems with background technology]

However, the system configured as described above has various drawbacks as follows.

(1) Data from each terminal device must be collected while carrying several cassette recorders, making the data collection work complicated and extremely tiring.

(2) Since the standard time is once stored in each cassette recorder and then the time signal for time adjustment is supplied to each terminal device, it is necessary to always carry a standard clock for time adjustment. Ta.

(3) Since the time of each terminal device is adjusted in the order of standard clock → cassette recorder → terminal device, if the clock accuracy of each device is not high, errors will occur when the time is adjusted.

(4) Since data collection is done by collection staff, as the number of terminals increases, labor costs increase and it is not efficient.

(5) Since data is collected every fixed period of time, once the clock time goes out of order, the data from the date of data collection to the date of the next data collection becomes invalid.

[Purpose of the invention]

The present invention has been made with attention to the above points, and it is possible to easily adjust the arbitrary clock of each terminal device to an arbitrary time, and furthermore, it is possible to select each terminal device without going through any manual steps. An object of the present invention is to provide a road survey system that can automatically collect data.

[Summary of the invention]

The present invention includes a central device equipped with a standard clock, which selects a desired terminal device by sending out a standard time signal and a polling signal, and also adjusts the time of the clock circuit of the terminal device. The terminal device uses the time signal before time adjustment as a return signal and sends the time limit data with time adjustment to the central device, and the central device detects the difference between the time signal from the terminal device and the standard time signal. This is a road survey system that understands the situation and takes necessary leases when necessary.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. 1 is a schematic diagram of the entire system, FIG. 2 is a block diagram of a terminal device, and FIGS. 3 and 4 are diagrams of transmission procedures and transmission formats. This system consists of a central device 10 and a plurality of terminal devices 20A, 20B... These terminal devices 20A, 20B... are connected using a communication line 30 such as a telephone line or a low-voltage electric wire derived from the central device 10. has been done. The central device 10 includes a device body 11 that includes a computer, etc., and a standard clock 12 that clocks and outputs standard time.
and a modulation/demodulation circuit 13 (hereinafter referred to as a modem) that modulates and demodulates a transmission signal, and is configured to send out a polling signal with a terminal calling address, a control code, a standard time signal, etc.

Each terminal device 20A, 20B, . . . is configured as shown in FIG. In Figure 2, 21 is the load voltage
This circuit 21 is a power conversion circuit that obtains power by multiplying V _L and consumption current I _L , and this circuit 21 is configured to, for example,
A multiplication element that multiplies V _L and current consumption I _L , a power-to-frequency conversion circuit that converts the multiplied power into the number of pulses, and converts the output of this conversion circuit into the number of pulses corresponding to the amount of power used. It consists of a frequency dividing circuit. 22 is a counter that counts the output pulses of the power conversion circuit 21, and this count value is calculated by the clock circuit 2.
3 to the subsequent memory 2 at fixed time intervals based on signals input from the control circuit 24 at fixed time intervals.
5. This clock circuit 23 always sends a current time signal and a time limit signal to a control circuit 24. Further, the control circuit 24 receives a polling signal from the central device 10 and performs necessary control on each component, ie, the counter 22, the memory 25, the signal conversion circuit 26, and the like. This data conversion circuit 26 is
Parallel data from the memory 25 is converted into serial data and transmitted to the communication line 30 via a modem path (hereinafter referred to as modem) 27, and serial data input from the central unit 10 via the modem 27 is converted into serial data. It has a function of converting it into data and inputting it to the control circuit 24. Reference numeral 28 denotes a terminal address setting section, which has a unique address for each terminal device 20A, 20B, . The address setting means of the terminal address setting section 28 is a slide switch or a jumper wire.

Next, the operation of the system configured as above will be explained. Each terminal device 2 in the central device 10
When collecting timed data stored in 0A, 20B, etc., the following procedure is used.
First, the device main body 11 outputs a polling signal S1 and a standard time signal A from the standard clock 12 based on a sequence program of a computer or the like or an operator's operation, and modulates it with the modem 13.
It is transmitted to the communication line 30 in the order shown in the upper row of FIG.
Actually, the data format from the central unit 10 is a standard time signal including a transmission start code STX, a terminal calling address TAD, a control code CCD, and, for example, year, month, day, hour, minute, and second, as shown in FIG. A and a transmission completion code ETX.

When each terminal device 20A, 20B... receives a signal in the above data format,
After demodulating with the modem 27, the signal conversion circuit 2
6 converts the serial signal into a parallel signal and supplies the converted signal to the control circuit 24. Here, the control circuit 24 compares the terminal calling address and its own terminal address successively sent from the terminal address setting unit 28, and if they match, it sets its own terminal address TAD and the clock circuit as shown in the lower part of FIG. The current time signal B of 23 is used as a return signal, and the signal conversion circuit 2
6 performs predetermined signal conversion, and furthermore, modem 27
The signal is modulated and transmitted to the central device 10.

Further, the terminal device selected by the central device 10, for example 20A, sends out the current time signal B of the clock circuit 23 as described above, and then sends the current time signal B to the control circuit 23.
4, the time is corrected by writing the standard time signal A sent from the central unit 10 into the clock circuit 23.

On the other hand, upon receiving the return signal from the terminal device 20A, the central device 10 confirms that the terminal device 20A has been selected based on the terminal address TAD, and
The time signal B of the terminal device 20A is compared with the standard time signal of the standard clock 12, and if there is a time difference of more than a predetermined value, a warning signal is issued to notify the operator. Here, a maintenance person goes to the installation location of the terminal device 20A and repairs or replaces the clock circuit 23.

Further, when the central device 10 completes receiving the return signal, the central device 10 sends the terminal device 20A to the terminal calling address TAD as shown in the upper part of FIG. 3.
and a polling signal S2 consisting of a control code CCD.

Here, the terminal device 20A is the central device 10.
When the polling signal S2 is received, it is input to the control circuit 24, and under the control of the control circuit 24, the time limit data (see the lower part of FIG. 3) in the memory 25 is read out and transmitted to the central unit 10. Thereafter, the terminal device 20A writes the count value of the counter 22 for each time period into the memory 25 based on the standard time signal A sent from the central device 10. Through the above procedure, each terminal device 20A, 20B
Completed time adjustment and collection of timed data.

Therefore, according to the above configuration, the central device 10 sends out a polling signal via the communication line 30, selects one of the plurality of terminal devices 20A, 20B, etc., and collects timed data. This configuration eliminates the need for collection personnel as in the past, making collection work more efficient and making effective use of personnel. Also, at the same time as the polling signal for terminal selection, a standard time signal is sent to the clock circuit 2 in the terminal device.
3, the time is corrected directly, so there is no problem of time correction deviation as in the conventional case, and the time can be corrected accurately. In addition, if timed data is collected from the central device 10 every one to two weeks, even if there is a loss of data during that time due to a failure of a terminal device, the failure can be repaired quickly, and the reliability of the data can be improved. The recovery rate will improve. In addition, the terminal devices 20A, 20
Even if the time of the clock circuit 23 of B is incorrect due to the influence of temperature, voltage, etc., the incorrect time is collected by the central device 10 when data is collected, so the time error of the clock circuit 23 can be immediately grasped, and when necessary measures can be taken. Further, it is also possible to only adjust the time from the central device 10 to the terminal devices 20A, 20B, . . . every short period (for example, several days), so that the time error can be extremely reduced.

In the system of the present invention, the central device 10' and the terminal device 20' may be connected using a telephone line 30', as shown in FIG. 5, for example. In the figure, 31 is an exchange. That is, as the central device 10',
In addition to the components 11 to 13 shown in FIG. 1, a central network control device 14 and a telephone 15 are provided on the output side of the modem 13. The terminal device 20' is
Original terminal device body 31 (device 20A in FIG. 1...
), a terminal-side network control device 32, a telephone 33, etc. In this system, when a subscriber is called by a subscriber number, the exchange 31 calls the subscriber and connects the central unit 10' and the terminal device 20' which is the subscriber. After the line is connected, the operation is exactly the same as in FIG.

In addition, in the present invention, upon receiving the standard time signal and polling signal from the central device 10, the terminal side may correct the time of the clock circuit 23 after transmitting time limit data. Furthermore, although two polling signals are used, it is also possible to control all of the terminals with one polling signal.

〔Effect of the invention〕

As described in detail above, according to the present invention, time-limited data can be collected by easily selecting a terminal device at any time from the central device, and when data is collected, a standard time signal is sent at the same time as a polling signal to the terminal device. Since the time of the clock circuit is corrected, time management can be performed accurately. In addition, since the return signal from the terminal device includes the time of the terminal side clock circuit, the central device side can grasp the time difference of the terminal.
We can provide a road survey system that allows clock circuits to be repaired or replaced when necessary.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing one embodiment of the road survey system according to the present invention, FIG. 2 is a block diagram of each terminal device in FIG. 1, and FIGS. 3 and 4 are transmission procedures and transmission formats. FIG. 5 is a schematic configuration diagram showing another example of the system of the present invention. 10, 10'...Central device, 11...Device main body,
12... Standard clock, 13... Modem, 20', 2
0A, 20B...terminal device, 22...counter,
23... Clock circuit, 24... Control circuit, 25...
Memory, 26... Signal conversion circuit, 27... Modem, 28... Terminal address setting unit.

Claims (1)

[Scope of Claims] 1. In a road survey system in which a central device sequentially selects desired terminal devices via a communication line and collects timed data, the central device comprises: a standard clock that keeps track of standard time; central signal sending means for reading the standard time from the standard clock for each terminal device at a required time and sending out a standard time signal and a polling signal for terminal selection; each terminal device: a timed data acquisition means that generates a timed signal from a clock section and stores a counted value of the number of pulses proportional to the measured value as timed data; a terminal address setting section that sets its own terminal address in advance;
The polling signal sent from the central device is compared with the own terminal address of the terminal address setting section, and when they match, it is determined that the call is from the own terminal, and the current time signal of the clock section and the time limit data are a terminal-side signal calling means for sending a signal to the central device; and a time correction device for correcting the time by writing a standard time signal from the central device to the clock section after sending the time limit data from the terminal-side signal sending means. A road survey system comprising: means. 2. The road survey system according to claim 1, wherein the polling signal has a terminal calling address and a control code.