JP2008235043A - Illumination light control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correctly detect short-circuit of a light control signal line independently for every system without causing a cost increase, in an illumination light control system to dimly control a plurality of systems of luminaire groups by transmitting a light control signal from a light control device. <P>SOLUTION: The light control signal S is transmitted to each of the light control signal lines La, Lb, Lc, Ld, and a luminaire group connected to each of the light control signal lines La, Lb, Lc, Ld individually emits light in accordance with the on-duty of the light control signal S. If short-circuit st occurs in the light control signal line Lc at the time t1, a short-circuit detecting signal Ps is output, transmission of the light control signal S to each light control signal line is stopped system by system in order of the control signal line La, Lb, Lc, Ld, The light control device confirms whether or not generation of the short-circuit detecting signal Ps is stopped at the time t3, t4, t5 when transmission of the light control signal S to each of the light control signal lines La, Lb, Lc, Ld is stopped, and specifies the light control signal line Lc in which short-circuit has occurred based on the timing (t4) when the output of the short-circuit detecting signal Ps stops. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an illumination dimming control system that transmits a dimming signal from a dimming control device and performs dimming control on a plurality of lighting fixture groups in a concentrated manner.

  A lighting device is known in which a plurality of lighting fixtures are connected in parallel to a single dimming control device via a dimming signal line, and the lighting fixtures are dimmed and controlled by a dimming signal transmitted from the dimming control device. (For example, refer to Patent Document 1). In the lighting device described in Patent Literature 1, each lighting fixture includes a circuit that monitors the lighting state and short-circuits the dimming signal line when the lighting state becomes defective (such as non-lighting or half-wave discharge). The dimming control device includes a short-circuit detection circuit that detects that the dimming signal line is short-circuited, and a display device that notifies the occurrence of an abnormality when the short-circuit detection circuit detects a short circuit. Even when the lighting state of one of the lighting fixtures becomes defective, the occurrence of the failure can be reliably notified to the user.

  On the other hand, a plurality of lighting fixture groups are connected to each system via a plurality of dimming signal lines with respect to one dimming control device, and the dimming control device separately controls dimming for each lighting fixture group. A dimming control system that performs control is known.

  Hereinafter, the dimming control system will be described with reference to FIG. The dimming control system 100 includes a plurality of fluorescent lamp lighting fixtures 100Fa1 to 100Fa3 as a lighting fixture group, a fluorescent lamp lighting fixture group 100Fb having a plurality of fluorescent lamp lighting fixtures 100Fb1 to 100Fb3, and a plurality of fluorescent lighting fixtures 100Fb1 to 100Fb3. The incandescent lamp lighting fixture group 100R having the incandescent lamp lighting fixtures 100R1 to 100R3 and the LED lighting fixture group 100E having the plurality of LED lighting fixtures 100E1 to 100E3, each of the lighting fixture groups 100Fa, 100Fb, 100R, and 100E are 1 One dimming control device 102 is connected as a separate system via a plurality of dimming signal lines 100La, 100Lb, 100Lc, and 100Ld.

  The dimming control device 102 includes a control unit 123 to which driving power is supplied by the power supply unit 122, and a PWM signal (a predetermined on-duty PWM signal) that is controlled by the control unit 123 to the dimming signal lines 100La, 100Lb, 100Lc, and 100Ld. Dimming signal driving units 101a, 101b, 101c, and 101d that output dimming signals), and short-circuit detection units 102a, 102b, 102c, and 102d connected to the dimming signal lines 100La, 100Lb, 100Lc, and 100Ld, It has. The control unit 123 receives an input of a command signal from the infrared remote controller 103 via the infrared light receiving unit 127, and controls each dimming signal driving unit 101a, 101b, 101c, 101d based on the command signal to control each dimming. The signal drivers 101a, 101b, 101c, and 101d output a PWM signal having a predetermined on-duty. Each of the lighting fixture groups 100Fa, 100Fb, 100R, and 100E emits light with an optical output corresponding to the on-duty of the PWM signal (the dimming signal) input via the dimming signal lines 100La, 100Lb, 100Lc, and 100Ld.

For example, the dimming signal driving unit 101a outputs a PWM signal with an on-duty of 80% to the fluorescent lamp luminaire group 100Fa, and each of the fluorescent lamps 100Fa1 to 100Fa3 emits light with an optical output of 20%. The drive unit 101c outputs a PWM signal with an on-duty of 90% to the incandescent lamp luminaire group 100R, and each of the incandescent lamps 100R1 to 100R3 emits light with an optical output of 10%. When the lighting state detection device provided in each lighting fixture detects an abnormality such as non-lighting or half-wave discharge, the dimming signal lines 100La, 100Lb, 100Lc, 100Ld to which the lighting fixture that has detected the abnormality is connected. Are short-circuited, and the short-circuit detection units 102a, 102b, 102c, and 102d of the dimming signal line detect the short-circuit.
JP 2004-335109 A

  In the lighting device described in Patent Document 1, each of a plurality of lighting fixtures connected to one dimming control device via a dimming signal line has a lighting state detection circuit, and the lighting state detection circuit is When the lighting state failure is detected, the dimming signal line is short-circuited. Therefore, the dimming control device can recognize that one of the lighting fixtures connected to the dimming signal line is defective. There is no suggestion about the case where a plurality of lighting fixture groups are connected to one dimming control device.

  On the other hand, in the dimming control system 100 shown in FIG. 4 described above, the dimming signal lines 100La, 100Lb, 100Lc, and 100Ld of each system are provided with the short-circuit detection units 102a, 102b, 102c, and 102d. Although it has an advantage that it can detect a defective lighting state generated in each of the lighting fixture groups 100Fa, 100Fb, 100R, and 100E, it must include the same number of short-circuit detection units 102a, 102b, 102c, and 102d as the number of systems. There was a problem of incurring high costs.

  Therefore, the present invention causes a high cost in the lighting dimming control system that controls the lighting of a plurality of lighting fixture groups by transmitting a dimming signal from the dimming control device via the dimming signal line. An object of the present invention is to provide an illumination dimming control system capable of correctly detecting a short circuit of a dimming signal line connecting each lighting fixture group for each system with a simple configuration.

  In order to achieve the above object, the invention of claim 1 includes a plurality of lighting fixture groups, a dimming control device that transmits a dimming signal to the plurality of lighting fixture groups, and the plurality of lighting fixture groups. In a lighting dimming control system comprising a plurality of dimming signal lines for connecting the dimming control device as a separate system for each lighting fixture group, the dimming control device includes one of the dimming signal lines. Or a short circuit detection unit connected in common to all, and when the short circuit detection unit detects a short circuit of any of the dimming signal lines, to the dimming signal line connected to the short circuit detection unit The dimming signal transmission is stopped one by one in order, and the dimming signal line in which the short-circuit has occurred is specified based on the timing at which the short-circuit detecting unit stops detecting the short-circuit.

  According to a second aspect of the present invention, in the illumination dimming control system according to the first aspect, the dimming control device sequentially stops transmission of the dimming signal to the dimming signal line one by one, and the short circuit After identifying the dimming signal line in which the short circuit has occurred based on the timing at which the detection unit no longer detects the short circuit, other dimming signal lines excluding the identified dimming signal line (hereinafter referred to as unspecified dimming signal line) When the transmission of the dimming signal is resumed, when the short-circuit detection unit detects a short circuit again, the transmission of the dimming signal to the unspecified dimming signal line is stopped one by one in order, It is characterized in that the process of identifying another dimming signal line in which a short circuit has occurred is repeated based on the timing at which the short circuit detection unit stops detecting a short circuit.

  According to the first aspect of the present invention, when the short circuit detection unit detects a short circuit of any one of the dimming signal lines, transmission of the dimming signal to the dimming signal line connected to the short circuit detection unit is performed one system at a time. Since the dimming signal lines that are short-circuited are identified based on the timing at which the short-circuit detection unit stops detecting the short-circuit, the number of short-circuit detection units is less than the number of dimming signal lines (number of systems). And the abnormal state of the luminaires of each luminaire group can be correctly detected for each system.

  According to the invention of claim 2, after the dimming signal line in which a short circuit has occurred first is specified, to other dimming signal lines excluding the specified dimming signal line (hereinafter referred to as unspecified dimming signal line) If the short circuit is detected again when the transmission of the dimming signal is resumed, the dimming signal transmission to the unspecified dimming signal line is stopped one by one in order, and the short circuit detection unit detects the short circuit. Since the process to identify other dimming signal lines that have short-circuited is repeated based on the timing at which they do not occur, even if a short-circuit occurs almost simultaneously in another dimming signal line, a short-circuit occurs Thus, it is possible to correctly detect the dimming signal lines of a plurality of systems.

(First embodiment)
An illumination dimming control system according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the dimming control system 1 of the present embodiment includes a dimming control device 2 that transmits a dimming signal S to four systems of dimming signal lines La, Lb, Lc, and Ld, A remote controller 3 that is operated by a user to output an operation signal to the dimming control device 2, and fluorescent lamp luminaires Fa, Fb, incandescent lamps respectively connected to the dimming signal lines La, Lb, Lc, Ld The lighting fixture group R and the LED lighting fixture group E are provided.

  The fluorescent lamp lighting fixture group Fa includes three fluorescent lamp lighting fixtures Fa1, Fa2, and Fa3, and the fluorescent lamp lighting fixture group Fb includes three fluorescent lamp lighting fixtures Fb1, Fb2, and Fb3, and an incandescent lamp lighting fixture. The group R includes three incandescent lamp luminaires R1, R2, and R3, and the LED luminaire group E includes three LED luminaires E1, E2, and E3. The lighting fixtures Fa1 to Fa3, Fb1 to Fb3, R1 to R3, and E1 to E3 of each lighting fixture group Fa, Fb, R, and E are connected in parallel to the dimming signal lines La, Lb, Lc, and Ld. . The dimming signal S is a PWM (Pulse Width Modulation) signal.

  Lighting circuits (not shown) for the fluorescent lamp luminaires Fa1 to Fa3 and Fb1 to Fb3 convert the oscillation cycle of the power supply power according to the PWM signal (dimming signal) input via the dimming signal lines La and Lb. Then, the light is supplied to a fluorescent lamp that is a light source, and the fluorescent lamp emits light with a light output corresponding to the oscillation period. The lighting circuits (not shown) of the incandescent lamp luminaires R1 to R3 and the LED luminaires E1 to E3 have power supply power according to PWM signals (dimming signals) input via the dimming signal lines Lc and Ld. The output phase angle is converted and supplied to an incandescent lamp and an LED lamp, which are light sources, and the incandescent lamp and the LED lamp emit light with a light output corresponding to the phase angle. In the present embodiment, the fluorescent lamp luminaires Fa1 to Fa3, Fb1 to Fb3 and the incandescent lamp luminaires R1 to R3 have a light output that decreases substantially in proportion to an increase in the on-duty of the input PWM signal. In E1 to E3, the optical output increases exponentially as the on-duty of the input PWM signal increases.

  In addition, each of the lighting fixtures Fa1 to Fa3, Fb1 to Fb3, R1 to R3, and E1 to E3 each short-circuit the dimming signal lines La, Lb, Lc, and Ld when detecting an abnormality in the lighting state. Fa3s, Fb1s to Fb3s, R1s to R3s, E1s to E3s are provided. Each of the short-circuit portions Fa1s to Fa3s, Fb1s to Fb3s, R1s to R3s, and E1s to E3s includes, for example, an illuminance sensor (not shown) that detects the illuminance of each lighting fixture, and each when the illuminance sensor detects a decrease in illuminance. It includes a transistor (not shown) that shorts the dimming signal lines La, Lb, Lc, and Ld for a predetermined time.

  The dimming control device 2 includes a control unit 23 configured by a microprocessor to which a predetermined operating voltage is supplied from a commercial power source 21 via a power source unit 22 and each dimming signal controlled by a control signal from the control unit 23. Dimming signal driving units A, B, C, and D that output the on-duty dimming signal S (PWM signal) corresponding to the control signal to the lines La, Lb, Lc, and Ld, and on for each type of lighting fixture A storage unit 26 that stores an information table in which a light output value corresponding to a duty value is recorded, and an infrared receiving unit that receives infrared rays transmitted from the infrared remote controller 3 and outputs a command signal superimposed on the infrared rays to the control unit 23. Unit 27, an alarm device 29 for notifying the user of the abnormal state for each of the lighting fixture groups Fa, Fb, R, E detected by the control unit 23, and dimming signal lines La, Lb, L Comprises a single short circuit detector 25 connected in common to Ld, a. The alarm device 29 can be configured by a lamp such as an LED that outputs light of different colors for each system, a speaker that outputs sound, and the like. Further, the infrared light receiving unit 27 may receive a specific low-power radio or other radio wave.

  When the control unit 23 receives an appropriate command signal from the infrared remote controller 3 via the infrared light receiving unit 27 (for example, “lights the fluorescent lamp illumination device group Fa with a light output of 50%”), the control unit 23 The dimming signal driving unit searches the information table stored in the storage unit 26 for an on-duty value at which each of the fluorescent lamp lighting fixtures Fa1 to Fa3 in the lighting fixture group Fa becomes the designated light output (50%). A is controlled to output a dimming signal S (PWM signal) of the on-duty value, and each fluorescent lamp luminaire Fa1 to Fa3 of the luminaire group Fa emits light at a designated light output (50%). .

  Next, the operation of the dimming control device 2 will be described with reference to the timing chart of FIG. 2 when a short circuit occurs in the dimming signal line Lc connected to the incandescent lamp luminaire group R. Now, when the power of the dimming control device 2 is turned on, the dimming signal driving units A, B, C, and D respectively send the dimming signal S having predetermined on-duty values to the dimming signal lines La, Lb, and Lc. , Ld to each of the lighting fixture groups Fa, Fb, R, E, and the lighting fixtures of each of the lighting fixture groups Fa, Fb, R, E emit light with a predetermined light output. The on-duty value of the dimming signal S transmitted to the dimming signal line La shown in FIG. 2 is about 25%, and the on-duty value of the dimming signal S transmitted to the dimming signal line Lb is about 83%. Similarly, the on-duty value of the dimming signal S transmitted to the dimming signal line Lc is about 58%, and the on-duty value of the dimming signal S similarly transmitted to the dimming signal line Ld is about 25%.

  Then, when an abnormality occurs in any of the lighting fixtures R1 to R3 in the incandescent lamp lighting fixture group R at time t1, and the dimming signal line Lc is short-circuited, each dimming signal line La, Lb, Lc, Ld The short-circuit detecting unit 25 connected in common detects the short-circuit st and outputs a short-circuit detection signal Ps to the control unit 23. When the control unit 23 receives the short circuit detection signal Ps from the short circuit detection unit 25, the control unit 23 sends a control signal to the dimming signal driving units A, B, C, and D in order to stop transmission of the dimming signal S. Output. Specifically, the control unit 23 stops the transmission of the dimming signal S from the dimming signal driving unit A at time t2, and the dimming signal from the dimming signal driving unit B at time t3 after a predetermined time lag. Similarly, transmission of S is stopped, and similarly, transmission of the dimming signal S from the dimming signal driver C is stopped at time t4. Since the dimming signal line Lc is short-circuited, the output of the short-circuit detection signal Ps from the short-circuit detection unit 25 is stopped when the transmission of the dimming signal S from the dimming signal drive unit C is stopped (t4). .

  The control unit 23 detects a short circuit at times t2, t3, t4... When the dimming signal S is stopped while sequentially stopping the transmission of the dimming signal S to the dimming signal lines La, Lb, Lc, and Ld. The presence / absence of the short circuit detection signal Ps from the unit 25 is determined, and based on the timing (t4) when the output of the short circuit detection signal Ps stops, it is specified which dimming signal line La, Lb, Lc, Ld is short circuited As a result, it is determined which system of the lighting fixture groups Fa, Fb, R, and E is abnormal. The control unit 23 identifies the short-circuited dimming signal line (Lc in the example of FIG. 2), and then determines the dimming signal S for the other dimming signal lines La, Lb, and Ld excluding the identified dimming signal line Lc. Transmission is resumed (t5). For the dimming signal line Ld, the dimming signal line Lc that has been short-circuited at the stage where the dimming signal S for the dimming signal line Lc has been stopped has been identified. The transmission of the dimming signal S is continued.

  Thereafter, the control unit 23 outputs to the alarm device 25 that an abnormality has occurred in any of the lighting fixtures R1 to R3 in the incandescent lamp lighting fixture group R. The mode of the alarm by the alarm device 25 may be a mode in which an abnormal LED is lit among four different LEDs provided corresponding to each system, or an incandescent lamp luminaire group R from a speaker. It is also possible to output a message that specifically indicates that an abnormality has occurred in any of the lighting fixtures R1 to R3.

  As described above, in the illumination dimming control system 1 of the present embodiment, the transmission of the dimming signal S to the dimming signal lines La, Lb, Lc, and Ld is sequentially stopped one by one, and each dimming signal line is stopped. The dimming signal lines La, Lb, Lc, and Ld in which the short circuit st is generated are identified based on the timing at which the output of the short circuit detection signal Ps from the short circuit detection unit 25 commonly connected to La, Lb, Lc, and Ld stops. Therefore, it is possible to determine which abnormal state has occurred in each of the lighting fixture groups Fa, Fb, R, and E by simply providing one short-circuit detection unit 25.

  In the present embodiment, there are four dimming signal lines La, Lb, Lc, and Ld connected to one control unit 23, but the dimming signal lines La, Lb, Lc, and Ld are More than five systems may be used, and in that case, instead of connecting one short-circuit detection unit 25 so as to be common to all dimming signal lines, each group divided into a plurality of systems You may make it connect the short circuit detection part 25 common to these. For example, in the above example, one short-circuit detection unit 25 is commonly connected to the dimming signal lines La and Lb, and one short-circuit detection unit 25 is commonly used for the dimming signal lines Lc and Ld. It may be connected.

(Second Embodiment)
An illumination dimming control system according to a second embodiment of the present invention will be described with reference to FIG. The illumination dimming control system 1 of the second embodiment has the same hardware configuration as the illumination dimming control system 1 of the first embodiment, and a description of the hardware configuration is omitted. In the illumination dimming control system 1 according to the second embodiment, the control unit 23 specifies the dimming signal line short-circuited by the processing procedure as described above, and then the dimming signal lines other than the specified dimming signal line. When the transmission of the dimming signal S to the unspecified dimming signal line (hereinafter referred to as “unspecified dimming signal line”) is resumed, the same processing is repeated for the unspecified dimming signal line when the short circuit is detected again Different from the first embodiment. In the illumination dimming control system 1 of the second embodiment, due to the above differences, even when a short circuit occurs almost simultaneously in a plurality of systems of dimming signal lines, the dimming signal line in which the short circuit has occurred is correctly detected. can do.

  Next, the operation of the dimming control device 2 in the illumination dimming control system 1 according to the second embodiment will be described with respect to a case where a short circuit st occurs simultaneously in the two systems of the dimming signal line Lb and the dimming signal line Lc. This will be described with reference to the timing chart 3. Before the short circuit st occurs (before the time t1), the dimming signal driving units A, B, C, and D each have a dimming signal having a predetermined on-duty value, as in the timing chart shown in FIG. S is transmitted to each lighting fixture group Fa, Fb, R, E via each dimming signal line La, Lb, Lc, Ld, and the lighting fixtures of each lighting fixture group Fa, Fb, R, E are predetermined Light is emitted with light output. Then, at time t1, when an abnormality occurs in any one of the fluorescent lamp luminaire group Fb and the incandescent lamp luminaire group R and the dimming signal line Lb and the dimming signal line Lc are short-circuited simultaneously, The short-circuit detection unit 25 connected in common to the dimming signal lines La, Lb, Lc, and Ld detects the short-circuit st and outputs a short-circuit detection signal Ps to the control unit 23. When receiving the short circuit detection signal Ps from the short circuit detection unit 25, the control unit 23 sequentially stops the transmission of the dimming signal S to the dimming signal lines La, Lb, Lc, and Ld. In the example shown in FIG. 3, since the dimming signal lines Lb and Lc are short-circuited, the short-circuit detection unit is stopped (t4) when transmission of the dimming signal S to the dimming signal line Lc is stopped. The output of the short circuit detection signal Ps from 25 stops. At the time (t3) when the transmission of the dimming signal S to the dimming signal line Lb is stopped, the short circuit st of the dimming signal line Lc still exists, and therefore the short circuit detection signal Ps is continuously output.

  Then, as in the first embodiment, the control unit 23 causes any of the dimming signal lines La, Lb, Lc, and Ld to be short-circuited based on the timing at which the short-circuit detection signal Ps from the short-circuit detection unit 25 stops. And the transmission of the dimming signal S to the dimming signal line other than the specified dimming signal line is resumed. In the second embodiment, after the transmission of the dimming signal S is resumed, When the short circuit st is detected again, substantially the same processing is repeated for the unspecified dimming signal line, and another shorted dimming signal line is specified.

  More specifically, the control unit 23 resumes transmission of the dimming signal S to the dimming signal lines (unspecified dimming signal lines) La, Lb, and Ld at time t5, and the dimming in which a short circuit has occurred. Since the transmission of the dimming signal S to the signal line Lb is resumed, the short circuit detection unit 25 outputs the short circuit detection signal Ps again. The control unit 23 recognizes the occurrence of the short circuit detection signal Ps again, and sequentially stops transmission of the dimming signal S to the unspecified dimming signal lines La, Lb, and Ld. That is, the control unit 23 stops transmitting the dimming signal S to the dimming signal line La at time t6, and stops transmitting the dimming signal S to the dimming signal line Lb at time t7 after a predetermined time lag. To do. Since the dimming signal line Lb is short-circuited, the output of the short-circuit detection signal Ps from the short-circuit detection unit 25 is stopped at time t7.

  The control unit 23 confirms that the output of the short circuit detection signal Ps is stopped at the time t7, and specifies that the other short-circuited dimming signal line is the dimming signal line Lb. Then, at time t8, the control unit 23 resumes transmission of the dimming signal S for the dimming signal lines La and Ld other than the dimming signal lines Lb and Lc that have been identified as being short-circuited, and the fluorescent lamp luminaire The user is notified via the alarm device 29 that an abnormality has occurred in the group Fb and the incandescent lamp luminaire group R.

  As described above, in the illumination dimming control system 1 according to the second embodiment, after the dimming signal line in which a short circuit has occurred is first specified, the specified dimming signal line (Lc in the above example) is excluded. When the short circuit is detected again when the transmission of the dimming signal to the dimming signal line (La, Lb, Ld in the above example) is resumed, the dimming signal S of the unspecified dimming signal line is detected. Processing for sequentially stopping transmission one by one and identifying another dimming signal line (dimming signal line Lb in the above example) in which a short circuit has occurred based on the timing at which the short circuit detection unit 25 no longer detects the short circuit st Therefore, even when the short circuit st occurs in the dimming signal lines La, Lb, Lc, and Ld of different systems almost simultaneously, the dimming signal lines La, Lb, Lc, and Ld of the multiple systems in which the short circuit has occurred are repeated. Can be detected correctly.

1 is a block diagram showing the overall configuration of an illumination dimming control system according to a first embodiment of the present invention. The timing chart of the light control signal transmitted to each light control signal line in the same illumination light control system, and the short circuit detection signal output from a short circuit detection part. The timing chart of the dimming signal transmitted to each dimming signal line in the illumination dimming control system which concerns on the 2nd Embodiment of this invention, and the short circuit detection signal output from a short circuit detection part. The block diagram which shows the whole structure of the conventional light control system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Illumination dimming control system 2 Dimming control apparatus 25 Short circuit detection part Fa Fluorescent-lamp luminaire group (luminaire group)
Fb fluorescent lamp luminaire group (luminaire group)
R Incandescent lamp lighting equipment group (lighting equipment group)
E LED lighting equipment group (lighting equipment group)
La, Lb, Lc, Ld Dimming signal line S Dimming signal st Short circuit

Claims (2)

A plurality of lighting fixtures,
A dimming control device for transmitting a dimming signal to the plurality of lighting fixture groups;
In a lighting dimming control system comprising a plurality of dimming signal lines connecting the plurality of lighting fixture groups and the dimming control device as separate systems for each lighting fixture group,
The dimming control device includes:
A short-circuit detector connected in common to all or part of the dimming signal line;
When the short-circuit detection unit detects a short circuit of any one of the dimming signal lines, the transmission of the dimming signal to the dimming signal line connected to the short-circuit detection unit is sequentially stopped one by one to detect the short circuit An illumination dimming control system characterized by identifying a dimming signal line in which a short circuit has occurred based on a timing at which the unit no longer detects a short circuit. The dimming control device includes:
The transmission of the dimming signal to the dimming signal line is stopped one by one in order, and the dimming signal line in which the short circuit has occurred is identified based on the timing at which the short circuit detection unit stops detecting the short circuit, and then identified. When transmission of a dimming signal to another dimming signal line (hereinafter referred to as an unspecified dimming signal line) other than the dimming signal line is resumed, Processing to stop the transmission of the dimming signal to the specific dimming signal line one by one in order, and identify the other dimming signal line in which the short circuit has occurred based on the timing at which the short circuit detection unit no longer detects the short circuit The illumination dimming control system according to claim 1, wherein:

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