DALI manual - Tridonic
DALI manual - Tridonic
DALI manual - Tridonic
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Designing a <strong>DALI</strong> application<br />
Maximum of 16 <strong>DALI</strong> scenes per <strong>DALI</strong> circuit<br />
The current on the <strong>DALI</strong> circuit must not exceed the maximum current of the power supply (<strong>DALI</strong> PS/PS1 =<br />
200mA or <strong>DALI</strong> PS2 = 240mA).<br />
The maximum cable length depends on the maximum permitted voltage drop along the <strong>DALI</strong> cable; this is<br />
defined as 2 V max. This corresponds to a maximum cable length of 300 m for a line cross-section of 1.5 mm²;<br />
contact resistance must also be taken into account. A voltage drop of 2V must not be exceeded.<br />
The recommended minimum cable cross-section is 1.5 mm²<br />
Current draw of the <strong>DALI</strong> circuit<br />
Each device in the <strong>DALI</strong> circuit consumes current via the <strong>DALI</strong> circuit. The total current draw on the <strong>DALI</strong> circuit must<br />
not exceed the maximum current of the <strong>DALI</strong> power supply.<br />
To determine the current draw of a <strong>DALI</strong> circuit both the current draw of the <strong>DALI</strong> devices and the current draw of the<br />
<strong>DALI</strong> controllers must be taken into consideration. The current draw of a <strong>DALI</strong> device is defined in the <strong>DALI</strong> standard<br />
as 2 mA. The current draw of the individual <strong>DALI</strong> controllers (ComfortDIM devices) is shown in the relevant data<br />
sheets.<br />
It is important that the current draw of the <strong>DALI</strong> circuit does not exceed the maximum current of the power supply. In<br />
the case of <strong>DALI</strong>-PS and <strong>DALI</strong>-PS1 this is 200 mA.<br />
Example: <strong>DALI</strong> circuit with 24 dimmable ballasts (PCA EXCEL), 3 <strong>DALI</strong>-GC and 3 <strong>DALI</strong>-SC<br />
Current draw of the individual <strong>DALI</strong> components (from the data sheet):<br />
Dimmable ballasts (PCA EXCEL) = 2 mA<br />
Group controllers (<strong>DALI</strong>-GC) = 6 mA<br />
Scene controllers (<strong>DALI</strong>-SC) = 6 mA<br />
Total current = Σ Current draw of <strong>DALI</strong> devices + Σ Current draw of <strong>DALI</strong> controllers<br />
Total current = 24 x ballasts + 3 x <strong>DALI</strong> GC + 3 x <strong>DALI</strong> SC<br />
Total current = 24 x 2 mA + 3 x 6 mA + 3 x 6 mA = 84 mA<br />
Maximum cable length<br />
The maximum cable length depends on the maximum permitted voltage drop along the <strong>DALI</strong> cable; this is defined as 2<br />
V max. Typically, this requirement is safely met for a cable length of 300 m and a cable cross-section of 1.5 mm².<br />
Additional voltage drops at terminal points must be taken into consideration. For cross-sections smaller than 1.5 mm²<br />
the maximum cable length is reduced accordingly.<br />
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