Dimming – Analogue Dimming – (DD4)

For Analogue Dimming, it is considered that there be two types, where both types are collectively referred to as being Analogue Dimming and these are given as 0-10 Volt Analogue Dimming and 1-10 Volt Analogue Dimming where both use separate AC power and control supply with one-way communication where the mains power to each of the luminaires in the circuit requires the installation of a 3 core mains supply (Live / Earth /  Neutral). The control function is by an additional signal pair cable which carries a low-speed signal, only used to control the dimming level and the usual method of control for this type of dimming system is typically by means of either a rotary dimmer or slider potentiometer.

It is not possible to assign individual control devices such as other dimmers or sensors to any one of the light fittings without installing additional wiring into the circuit.

The advantages of an analogue dimming system are that it is normally fairly easy to install, it is certainly simple to operate, and it can be used on a limited range and type of daylight sensors. It also has a fixed output which can be set using a resistor.

The disadvantages relate to its limitation in the suitability of application and the installation of lengthy control cables can cause a difference in the dimming levels within large open plan spaces, something which is caused by the volt drop within the control cable. A separate switch is required to operate the on/off control of the lighting, which may or may not be integrated into the dimmer being used.

Analogue Dimming – 0-10 Volt – (ANSI E1.3-2011)

The analogue system of 0-10Volt is detailed within ANSI E1.3 and the principal of the 0-10 Volt Dimming system was the first and simplest electronic lighting control system, where 0-10 Volt dimmers use a low voltage 0-10Volt DC signal connected to each LED power supply or Driver. At 0 Volts the device will dim the lighting connected to the dimmer to the minimum light level allowed by the dimming drivers, and at 10 Volts the device will have increase the lighting to operate at a level of 100% of output.

The operation of a 0-10 Volt analogue system will turn the lighting on at the minimum turn-on voltage, which is at 0.3 Volts and within the system, the control sources the current whereas the load sinks with the current.

Analogue Dimming – 1-10 Volt – (IEC 60929:2011)

The analogue system of 1-10 Volt is detailed within IEC 60929 and the principal of the 1-10 Volt Dimming system is where the Driver generates a 10 Volt signal which is then “pulled” down to a low level by a controller to the minimum level of 1.0 Volt, a level which is typically considered as being the minimum level which drivers can effectively operate at, and this will equates as being the minimum lighting level within the application. If at any time, the signal is broken, the lights would revert to operating full brightness due to the driver generating a 10 Volt signal.

The operation of a 1-10 Volt analogue system will control the lighting system down to 1 Volt and the minimum operating voltage is at around 0.7-0.8 Volts, where the light source will not be turned off completely unless switched through another independent action. It will provide illumination from the minimum up to 10 Volts for maximum light and where the load sources the current whereas the control sinks with the current.