Installation Guide

change-over switch, switching the digital input between plus and minus (ground GND) of the vehicle electri-
cal system voltage (+9 ... 30 V).
If no change-over switch is available, an electric load for example, indicator light or resistor, between the
digital input and ground (GND) or between the digital input and the vehicle voltage (+9 ... 30 V) can offer
defined levels.
When using inductive loads, a free-wheeling diode must be used in parallel with the load.
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