The smoke alarm is composed of an infrared light-emitting tube, a series feedback photosensitive circuit composed of a phototransistor, a semiconductor tube switching circuit and an integrated alarm circuit, as shown in FIG. When the monitored environment is clean and free of smoke, the infrared light emitting diode VD1 emits light with a pre-adjusted initial current. After the infrared light is received by the phototransistor VT1, the internal resistance is reduced, so that the current in the series circuit of VD1 and VT1 is increased, the luminous intensity of the infrared light emitting diode VD2 is correspondingly increased, and the internal resistance of the phototransistor is further reduced. This cycle forms a strong positive feedback process until the current in the series photo-sensing circuit reaches a maximum value. The voltage drop generated on R1 turns VT2 on through VD2, VT3 turns off, and the alarm circuit does not work.
When the smoke in the monitored environment increases sharply, the light transmittance in the air deteriorates. At this time, the luminous flux received by the phototransistor VT1 decreases, the internal resistance increases, and the current in the series photosensitive circuit also decreases. The luminous intensity of the diode VD1 also decreases. This cycle forms a process of negative feedback, so that the current in the series photosensitive circuit is reduced to the initial current value, the voltage on R1 is also reduced to 1.2V, so that VT2 is cut off, VT3 is turned on, the alarm circuit works, and an alarm is issued. signal. C1 is set to prevent the interference of short-term smoke.
Figure: Smoke alarm circuit
IP67 Aluminium Case Led Driver
IP67 Aluminum Case Led Driver
A comprehensive range of IP Rated/Waterproof AC/DC long life span led driver suitable for use in a range of Lighting applications, including Street lighting, Architectural Lighting, Task Lighting, Medical Lighting, Transportation Lighting, Entertainment Lighting, Moving Signs, Safety & Security Lighting and Outdoor Area Lighting Applications. LED Lighting power supplies & LED Drivers in constant voltage or constant current models IP67 rated. waterproof led driver,48V led driver.
Advantage: High Power Led Driver, safety and stability, high pressure test protection, short circuit protection, anti-lightning strong, safe level Certification, UL TUV FCC, etc. certification.
Parameter:
Input ovltage:100-277V
Output voltage(different range):24-38V/30-42V/36-54V/45-76V/72-143V
Current:100-5000mA
Power factor:>0.95
THD:<15%
Dimming: 0-10V/PWM/RX
Housing: Aluminum
What's the benefits of Fahold Linear Lights driver?
- Standard Linear Lighting
- Cost-effective light-line solution for industry,commercial and other applications
- Good quality of light with 5years warranty, EMC, EMI, safety SELV design
- Easy to order and install,requiring less time,reducing packaging waste and complexity
- Flexible solution
Question 1:Are you a factory or a trading company?
Answer: We are a factory.
Question 2: Payment term?
Answer: 30% TT deposit + 70% TT before shipment,50% TT deposit + 50% LC balance, Flexible payment
can be negotiated.
Question 3: What's the main business of Fahold?
Answer: Fahold focused on LED controllers and dimmers from 2010. We have 28 engineers who dedicated themselves to researching and developing LED controlling and dimming system.
Question 4: What Fahold will do if we have problems after receiving your products?
Answer: Our products have been strictly inspected before shipping. Once you receive the products you are not satisfied, please feel free to contact us in time, we will do our best to solve any of your problems with our good after-sale service.
Waterproof Led Driver,Long Life Span Led Driver,48V Led Driver,led constant current driver,driver for led light
ShenZhen Fahold Electronic Limited , https://www.fahold.net