My full code as a backup and some useful reminders that are difficult to find online.

In order not to spam z-wave communication. Only send a command when the value has changed > 4 (0-255). A join block before this combines the current (msg.payload.huidig) and setpoint (msg.payload.aansturing). Here we send the first node output only when the difference between set and current is > 4.

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Full code below, this gets messy

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