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    Signal & Communication

    I measure a DALI voltage but communication is unreliable, how do I fix it?

    By Lichtvision Engineering · Published

    Short answer

    A correct voltage doesn't guarantee reliable communication. The most common causes are too many devices on one line (the limit is 64), excessive current draw from incorrect wiring, or a bus power supply that is too weak. Disconnect branches one at a time and watch whether communication improves. ProbitSite's signal-quality measurement points to the exact segment or device causing the problem.

    The three usual causes

    Most reliability problems on a powered bus come down to one of three things: more than 64 devices on a single line, excess current draw from incorrect wiring, or an undersized or weak bus power supply.

    How to isolate it

    Disconnect branches of the installation systematically and check whether communication improves after each step. The branch that restores reliability contains the fault.

    How ProbitSite pinpoints it

    ProbitSite's signal-quality measurement shows exactly which segment or device is dragging the line down, so you don't have to guess which branch to chase.

    unreliable communicationsignal qualitytoo many devices64 devicespower supplywiring

    Diagnose DALI issues like this in seconds

    ProbitSite is the DALI-2 certified handheld multimeter built for exactly this kind of on-site fault finding.

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