WIRELESS DETECTION DEVICE

• US 20130099904A1
• Filed: 09/14/2012
• Published: 04/25/2013
• Est. Priority Date: 10/20/2011
• Status: Active Grant

• Current Assignee: Schneider Electric Industries SAS (Schneider Electric SE)
• Original Assignee: Schneider Electric Industries SAS (Schneider Electric SE)
• Inventors: RAISIGEL, Hynek, Leger, Eric
• Granted Patent: US 8,981,911 B2
• Time in Patent Office: Days
• US Class Current: 340/12.22
• CPC Class Codes: H05B 47/105 in response to determined parameters
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: H05B 47/19 via wireless transmission
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

The invention relates to a detection device (2) designed to detect the intensity of a signal emitted by a source (12), said source (12) being powered by pulse-width modulation at a first frequency (f₀). The device comprises a reactivation circuit (22) comprising means (220) for detecting a signal modulated at a second frequency (f₁), the second frequency (f₁) being different from the first frequency (f₀), and tripping means (222) for tripping a reactivation of the detection device (2) when the signal is modulated at the second frequency (f₁).

Claims

1. Detection device for detecting the intensity of a signal emitted by a source, said source being powered by pulse-width modulation at a first frequency (f₀), said device comprising:

a standalone energy generator supplying a charging current (Icharge),

electrical energy storage means powered by the charging current (Icharge) supplied by the standalone energy generator,

a sensor designed to generate measurement values,

wherein the device comprises;

a reactivation circuit for the detection device, said reactivation circuit comprising tripping means for tripping a reactivation of the detection device when the signal is modulated at a second frequency (f₁), different from the first frequency (f₀), said reactivation circuit being connected to the standalone energy generator and said tripping means receiving as input a voltage that is a function of the charging current (Icharge) generated by the standalone energy generator,

means for detecting the signal modulated at the second frequency (f₁), said detection means comprising a resonant circuit,

a circuit for eliminating false reactivations, said false reactivations being due to a single variation of the intensity of the signal and/or to a modification of the duty cycle of the pulse-width modulation.

2. Device according to claim 1, wherein the circuit for eliminating false reactivations of the detection device comprises a rectifier circuit designed to detect a maximum amplitude of the charging current (Icharge).

3. Device according to claim 2, wherein the tripping means comprise a comparator with two inputs each of which has an electrical potential applied to it.

4. Device according to claim 3, wherein the first input of the comparator is connected to the rectifier circuit to receive a voltage equal to the sum of the voltage measured at the terminals of the resonant circuit and of the voltage measured at the terminals of the rectifier circuit and in that the second input of the comparator is connected to a reference voltage representative of the voltage at the terminals of the energy storage means.

5. Device according to claim 1, wherein the standalone energy generator comprises a photovoltaic module.

6. Device according to claims 1, wherein the sensor is a brightness sensor.

7. Communication system comprising:

a coordinator provided with a source of a signal modulated at a first frequency (f₀) by pulse-width modulation,

detection devices connected to said coordinator via a communication network,

wherein;

each detection device conforms to that defined in one of the preceding claims and

the source comprises means for emitting the signal modulated at a second frequency (f₁) in order to reactivate the devices and synchronise them.