JPS60195463A - Disconnection detecting system - Google Patents

Abstract

PURPOSE:To detect stably a disconnection under various conditions by providing a current-voltage converting means for generating a voltage by a current of an extent that a device to be started is not started, a reference voltage generating means and a voltage comparing means. CONSTITUTION:In a starting device side of a signal line 2 for connecting a start signal sending-out part 1 and a start signal detecting relay 4, a current-voltage converting part 6 for sending out a current I2 by which a device to be started in not started, and generating a voltage VP by the current I2, and a reference voltage generating part 7 for outputting a reference voltage VS are conncted to a voltage comparing part 8. In such a state, the comparing part 8 indicates the voltage VS<VP, but when the signal line 2 is abnormal, the current I2does not flow and the voltage VP is varied, and the comparing part 8 is constituted so as to generate an output as an abnormal state, namely, a disconnected state. In such a way, a factor for causing malfunction or non-operation is eliminated, and an electric condition for stable operation can be set.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a disconnection detection method in a communication line.

(Prior art) Conventionally, the method with a disconnection detection function in this field is M.
The circuit configuration is as shown in Figure J.

To briefly explain Fig. 1, starting signal detection relay 4
A disconnection detection current 1 (.11K) which does not operate is constantly supplied, and the disconnection detection relay 5 is always operated under normal conditions, that is, when the signal line (relay line) 2 is connected. In the event of an abnormality, that is, when the signal line (relay line) 2 becomes disconnected due to an artificial or natural phenomenon, the disconnection detection current 11 (CIIK) will not flow and the disconnection detection relay 5 will become inoperable. This allows the occurrence of a disconnection to be detected. In addition, J is a start signal sending part which puts the start signal detection relay 4 into a start waiting operation, 3 is a signal line resistance, and E is a power supply.

The disadvantage of this method is that the disconnection detection current '+ (C1fK) changes due to the resistance value of the signal line resistor 3, fluctuations in power supply voltage, ground potential difference, etc., resulting in malfunction or disconnection detection of the starting signal detection relay 4. The problem is that the relay 5 has an unstable factor that causes it to become inoperable.

Therefore, in order to specifically apply this type of detection circuit, it is difficult to set the electrical conditions for stable operation of the two relays, and there are restrictions on the application conditions and the selection of special relays. There was a need to do something like that.

(Object of the invention).

An object of the present invention is to solve these conventional drawbacks, and to enable stable detection of disconnection even under various signal line conditions.

(Structure of the Invention) For two purposes, the present invention is designed to reduce the disconnection detection check current to a minute current, and provide means for converting this current into a voltage and comparing it with a reference voltage.

(Example) Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a configuration diagram showing one embodiment of the disconnection detection circuit of the present invention, in which a signal line (relay line) 2 is connected to a starting signal transmitter 1 and a starting signal detection relay 4 via a signal line resistor 3. The two outputs of the current-voltage converter 6, which sends a current that does not cause the activated device to start to the starter, and generate the voltage VP from this current, and the reference voltage creator 7, which outputs the reference voltage Vs, are transferred to the voltage comparator. 8.

In such a configuration, the start signal detection relay 4 constantly flows a small current that does not operate, that is, the disconnection detection current 12 (.HK), to detect the normal state, that is, the state in which the signal 3 wire (relay wire) 2 is connected. In this case, this minute current is changed into a voltage by the current-voltage converter 6 to generate an output of VP.

On the other hand, the reference voltage generator 7 generates an output of the reference voltage Vs from a reference current (I8) set in advance.

Next, these two output voltages VP and VS are measured by a voltage comparison section 8.
The comparison is made with t (F
Let's do J.

Therefore, in the event of an abnormality, that is, when the signal line (relay line) 2 becomes disconnected due to an artificial or natural phenomenon, the disconnection detection current 12 (CIIK) stops flowing, and the output voltage of the current-voltage converter 6 V11 changes.

Next, since the voltage comparator 8 constantly compares the reference voltage vs and the output voltage vP of the current-voltage converter 6, it compares and detects the change in VP when the wire is disconnected, and uses the result to detect the abnormal state, that is, the disconnection. generates output as .

Next, the relationship between the voltages Vs and VP during normal and abnormal times, that is, when the wire is disconnected, is shown below.

Normal: Vs < Vp When disconnected: Vs)Vp, Vp=E Note that this embodiment describes an example of a one-line start signal system using electric oil sending out, or applies to a one-line starting signal system using earth air sending out. A similar idea can be applied to the case.

In this way, the disconnection detection current I 2 (CHK) changes depending on the magnitude of the signal line resistance, power supply voltage fluctuation, ground potential difference, etc.
The voltage Vp changes accordingly, but the value of the voltage Vs is V
The power supply voltage E common to S and Vp is slightly thicker (V
Since it is sufficient to set s>E), the relationship between Vs (Vp) can be maintained even when VP changes significantly, and stable disconnection detection becomes possible.

(Effects of the Invention) As explained above, the present invention makes the current for disconnection detection even smaller than the conventional method, and provides means for converting this small current into a voltage and comparing it with a reference voltage, which eliminates the drawbacks of the conventional method. This solves the problem and provides more stable functionality. In addition, in carrying out the present invention (5), it is possible to construct it with simple electronic component elements without using a conventional special relay, and with recent advances in electronic component technology, it is possible to make it even smaller. It has the advantage of being possible and has great economic effects.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a conventional wire breakage detection method, and FIG. 2 is a circuit diagram showing an embodiment of the wire breakage detection method of the present invention. 1. Start signal sending unit, 2. Signal line (relay #), 3.
. . . Resistor, 4. Starting signal detection relay, 5. Disconnection detection relay, 6. Current-voltage conversion section, 7. Reference voltage creation section, 8. Voltage comparison section. Patent applicant Oki Electric Industry Co., Ltd. (6)

Claims (1)

[Claims] Current-voltage converting means for sending a current that does not start a device to be activated to the starting device side in a one-line starting signal system communication line using a battery or ground air, and generating a voltage from the current, and a disconnection of the communication line. By providing a reference voltage generation means for determining the state and a voltage comparison means for comparing the reference voltage and the voltage generated by the current-voltage conversion means,
Disconnection detection method 0 characterized by detecting a disconnection state of the communication line