Method, liquid supply unit, and measurement device for a level indicator

The subject matter of the invention is a method for a printing machine with a printing device (5), in particular an inkjet printer, for applying liquid (22) onto a print material, with monitoring of the quantity of liquid in a liquid supply unit (1) by measuring the liquid level (23) with a sequential controller, wherein the measurement of the liquid level (23) is performed by a device (11), which detects the presence of liquid at the output of the printing device (5). Another subject matter of the invention is a liquid supply unit (1) for a printing machine with a printing device (5), in particular, an inkjet printer, for applying liquid (22) on a print material, with monitoring of the quantity of liquid in a liquid supply unit (1) by measuring the liquid level (23) with a sequential controller, wherein the measurement device (11) is suitable for measuring a fill level (23) and for controlling a liquid device (3). Furthermore, a measurement device (11), in particular, for a liquid supply unit (1), is the subject matter of the invention, in which at least one part of the measurement device (11) is made from circuit-board material.