Low-current inputs:
Typically, these beacons are supplied with power inputs. A model with power-inputs, is supplied by the input that is used to address the color and blink pattern. Therefore, the control output of the PLC must be able to provide its full operating current.
A model with low-current-inputs, is permanently supplied by pin 1 (BR). The remaining 3V-tolerant inputs are used to select the one of three color and blink patterns. This allows to drive these beacons by self-designed electronics with 3.3 or 5 V outputs.