Lighting Terms and Definitions-TJ2 Lighting

Triac Dimmer, LED 0-10v Dimming, PWM Dimming

Triac Dimmer

All phase-cutting dimmers work by switching the AC mains supply to the LED lamp on and off twice in every mains cycle. This has the effect of reducing the flow of electrical energy to the LED lamp or fixture, so reducing its light output.

There are two types of phase-cutting dimmers:

• Leading edge phase-cutting dimmers (also known as triac dimmers and rising edge dimmers). These work by switching the current off at the zero-crossing point (see diagram) and on again later in the same mains cycle. The amount of energy flowing to the LEDs depends on the duration of the “off” period. The longer the off period the dimmer the LEDs will appear to be.
• Trailing edge phase-cutting dimmers. These work by switching the current on at the zero crossing point (see diagram) and off later in the mains cycle. Usually, this is done with an electronic component called an isolated gate bipolar transistor (IGBT). The amount of energy flowing to the LEDs depends on the duration of the “off” period. The longer the off period the dimmer the LEDs will appear to be.

LED 0-10v Dimming

0-10V LED dimmer uses the DC voltage to control the output of the light fixture. This is one of the most straightforward and earliest lighting control systems. 0-10V dimming allows the smooth operation of light and dimming at the light levels of 10%, 1%, and 0.1%.

This system connects to your LED fixture, which allows you to choose the right light level based on your needs at the moment. For example, at 8V then the light fixture is at 80% output. If the signal is brought down to 0V, the light is at the minimum dim level, which could vary from 10% to 5% to 1%.

PWM Dimming

PWM dimming achieves the same effect by varying the duty cycle of a constant current in the string to effectively change the average current in the string.  The two key parameters in PWM dimming are the duty cycle and frequency:

The duty cycle is defined as the ratio of the amount of time the signal remains high to the total time of the cycle. It is expressed as a percentage and determines the illuminating level of a light source. A higher duty cycle results in a brighter light, while a lower duty cycle results in a lower illumination. For example, if the signal is constantly on, it is a 100% duty cycle.

The pulse width modulation (PWM) signal frequency is another crucial element. The PWM frequency determines how quickly a period—the amount of time it takes for the signal to turn on and off.

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Zigbee, Wi-Fi, And Bluetooth

Zigbee

Zigbee is a low-power, low-bandwidth needs, low-cost wireless communication protocol specifically designed for remote control and sensor applications, especially for small-scale projects. Hence, Zigbee is a low-power, low-data-rate, and close proximity (i.e., personal area) wireless ad hoc network. It operates on the IEEE 802.15.4 standard and forms the backbone of many smart lighting systems. Zigbee’s mesh networking capabilities allow devices to communicate with each other, forming a robust and reliable network even in large environments. This makes it ideal for smart lighting installations that require scalability and flexibility.

2.Wi-Fi

Wi-Fi, or Wireless Fidelity, is a ubiquitous wireless networking technology for large-scale projects. that enables high-speed internet access and local network connectivity. In the context of smart lighting systems, Wi-Fi connectivity provides seamless integration with existing home or office networks, allowing users to control their lights remotely via smartphone apps or voice assistants. Wi-Fi’s widespread adoption, high data rate and high bandwidth make it an attractive option for applications that demand real-time communication and high data throughput. But one of the disadvantage of wi-fi is the high cost and low efficiency which we couldn’t ignore.

3.Bluetooth

Bluetooth technology is widely recognized for its short-range wireless communication capabilities, typically used for connecting devices such as smartphones, tablets, and wearables. Bluetooth-enabled smart lighting systems offer a convenient and intuitive user experience, allowing users to control their lights directly from their smartphones without the need for additional hubs or gateways. Bluetooth’s low power consumption and compatibility with a wide range of consumer electronics make it an excellent choice for residential lighting applications.

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UVA, UVB, And UVC

UVA has the longest wavelengths among the three types, ranging from 315 to 400 nanometers. They constitute about 95% of the UV radiation that reaches the Earth’s surface. Unlike UVB and UVC, UVA rays can penetrate skin and even glass, making them a constant presence during daylight hours, regardless of weather conditions.

UVB has shorter wavelengths than UVA, ranging from 280 to 315 nanometers. They constitute about 5% of the UV radiation reaching the Earth’s surface. Unlike UVA, UVB is very biologically active but cannot penetrate beyond the superficial skin layers. It is responsible for delayed tanning and burning; in addition to these short-term effects, it enhances skin aging and significantly promotes the development of skin cancer. Most solar UVB is filtered by the atmosphere.

UVC have the shortest wavelengths, ranging from 100 to 280 nanometers. They are the most dangerous type of UV radiation but fortunately, they do not reach the Earth’s surface. The Earth’s atmosphere, particularly the ozone layer, absorbs UVC, preventing them from causing harm.

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IK Ratings

The IK ratings are an international standard used to measure the resistance of electrical enclosures to mechanical impacts. This standard is set by the International Electrotechnical Commission (IEC), specifically referenced in the standard IEC 62262. The IK rating ranges from IK00 to IK10, with higher numbers indicating greater resistance to mechanical impact.

IK Code	Protection	Description
IK00	There is no Protection.	–
IK01	Protected against 0.14 joules of impact	equivalent to the impact of a 0.25kg mass dropped from 56mm above
IK02	Protected against 0.2 joules of impact	equivalent to the impact of a 0.25kg mass dropped from 80mm above
IK03	Protected against 0.35 joules of impact	equivalent to the impact of a 0.2kg mass dropped from 140mm above
IK04	Protected against 0.5 joules of impact	equivalent to the impact of a 0.25kg mass dropped from 200mm above the impacted surface
IK05	Protected against 0.7 joules of impact	equivalent to the impact of a 0.25kg mass dropped from 280mm above the impacted surface
IK06	Protected against 1 joules of impact	equivalent to the impact of a 0.25kg mass dropped from 400mm above the impacted surface
IK07	Protected against 2 joules of impact	equivalent to the impact of a 0.5kg mass dropped from 400mm above the impacted surface
IK08	Protected against 5 joules of impact	equivalent to the impact of a 1.7kg mass dropped from 300mm above the impacted surface
IK09	Protected against 10 joules of impact	equivalent to the impact of a 5kg mass dropped from 200mm above the impacted surface
IK10	Protected against 20 joules of impact	equivalent to the impact of a 5kg mass dropped from 400mm above the impacted surface