Intelligent dimming lighting system

Based on a variety of lighting dimming methods on the market, the common dimming lighting system in KNX system can be roughly divided into the following categories:

1) Forward/back cutting dimming control;

2) 0-10V(1-10V) dimming control;

3) DALI digital dimming control system

4) DMAX 512 dimming control system

Since the dimming principles of each dimming system are not the same, they are widely used in the market and have their own dimming characteristics, the following items should be made clear during project construction and wiring:

(1) The wiring method of specific area shall strictly correspond to the project design scheme to design the regional dimming scheme. For the dimming scheme adopted in the project, wiring construction training shall be conducted with the site construction personnel in the early stage;

(2) It is clear that the lamp type of the lamp supplier should conform to the dimming scheme designed, and the dimming driver can be compatible with the dimming actuator in the system.

(3) Check the actual number of lighting loops at the site of the construction project, which should be different from the switching lighting loop, and make corresponding labels for the loop to facilitate line checking, installation and debugging in the future;

(4) Confirm the number and power of dimming lamps connected to each circuit to make preparations for the selection of dimming actuators and the balanced distribution of three-phase electricity in the later stage;

(5) Electrical protection equipment shall be installed at the front end of the switch actuator in the dimming system, and the installation process can facilitate daily or fault maintenance in the future.

1) Trailing Edge Dimmer/ Leading Edge dimmer dimming control

Before cutting the dimming control (leading edge cutting phase modulation light) for use on market at present most dimming control mode, also known as silicon controlled dimmer, Trailing Edge Dimmer the dimming (along the cut after phase modulation light) or MOS tube light given the dimming of the MOS tube cost price is high, with a small, market need special indicate when involved in such demand that move light, you need to specify the KNX manufacturer of MOS tube dimming actuators, But the wiring construction is the same as the forward cut dimming, do not do a separate description.

The principle of forward-cut dimming control is to change the input voltage in the circuit through the SCR signal. The switch in the silicon controlled appliance can adjust the internal resistance value, thus changing the conduction Angle of the silicon controlled, when the conduction Angle of the silicon controlled changes, the sine wave of the input voltage will deviate, the effective value of the voltage will become larger or smaller, and the brightness of the lamp will change accordingly.

According to the above dimming principle, SCR dimming wiring needs additional attention for:

1. Zero-fire wire in the dimming loop must be arranged separately. It is strictly prohibited to zero or co-fire with other loops.

2. It is best for a single LED lamp to use a separate 0-10V driver. Compatibility and matching between the driver and 0-10V should be done before debugging. If there are multiple lamps in a circuit wiring mode, the multiple drivers separately arranged in parallel for the overall dimming.

3. Clarify the type and rated power of lamps to match the corresponding general dimming actuator, and relevant suppliers to match the SCR driver.

The pros and cons of front cut dimming

Advantages: mature and stable technology, low dimming cost, strong compatibility, compatible with the original line, no need to re-wiring, simple installation.

Weakness: due to the principle of which destroyed the sine wave waveform, non sinusoidal waveform increase harmonic coefficient, and the disturbance signal at the same time, may produce certain current noise when using, dimming performance is bad, often leads to the dimming range, and can lead to minimum load is more than a single or a few LED light power rating. Because of the properties of the SCR half control switch, only the function of opening the current, but can not completely turn off the current, even if adjusted to the lowest there is still weak current flow, and LED micro current luminescence characteristics, so that there is a large number of SCR dimming after the LED still has weak light phenomenon.

Pay attention to the occurrence of the above problems when engineering installation and debugging, the line can increase resistance components, SCR driver with well-known brands in the market to match.