Q: What does LED stand for?

LED stands for Light Emitting Diode.
An LED light source comprises of a semiconductor fitted into an electrical circuit that provides light.

Q: What is colour temperature?

Colour temperature refers to the colour of the light source measured in degrees Kelvin (K). It is a measure of how much red, yellow, pure white and blue is in the light.
Warmer White: 3500K and less
Cooler White: 5000K and more
Normal Mid day Sunlight: 5600K

Q: What is the difference between constant voltage and constant current LED’s?

Constant Voltage LEDs use a resistor to control power through the LEDs. These systems require precise voltage throughout the circuit in order to provide even light across the system. These are less consistent due to voltage drops or inconsistent forward voltage through the system. Over or under driving LEDs can cause damage to the driver (power pack).

Constant current LEDs are regulated and have an on-board current driver to keep the current constant across the LEDs regardless of the voltage change (within range). These are more reliable and provide more consistent brightness across the system. It is possible to have much longer chains of constant current LEDs whilst still maintaining even brightness across the chain.

The longer the string of LEDs and the larger the load, the greater the voltage drop is likely to be.

Q: What is an IP rating?

The acronym “IP” stands for Ingress Protection and is a measure of the protection an item has against the ingress of dust or liquids. The first number refers to the protection level against dust, and the second number against liquids.

For example IP65, means the item is Dust Tight – No ingress of dust, and protected against water jets from any angle.

IP68 means Dust Tight and protected against submersion in water.

Q: What is the relation between Lumens and Watts?

Lumens (luminous flux) indicates the amount of light that is given off by a particular light source. Watts indicates the amount of energy which is consumed. It is important to measure an LED’s efficacy (Lm/w) to determine how much light is emitted per watt of energy consumed. LEDs with higher efficacy will require fewer drivers (power supplies) for the same level of brightness.

Q: What is CRI?

CRI stands for Colour Rendering Index and is the measure of how colours look under a light source compared with natural sunlight. The index measures from 0 to 100. The higher the number, the closer the colours would appear as if they were viewed under natural sunlight.