Page 6 AXIS 231D+/232D+ Installation GuideConnection Module Pinout• Digital Input (1-4) - connect to GND to activate or leave floating (unconnected) to deactivate• Transistor Output (1-4) - Max. load 100mA, max. voltage 24V DC. An open-collector NPN transistorwith the emitter connected to pin 2 (GND). If used with an external relay, a diode must be connectedin parallel with the load for protection against any voltage transients.LED indicatorsFunction Description Function Descriptionn/a not used GND groundn/a not used GND groundn/a not used Transistor Output 4 See belown/a not used Digital Input 4 See belown/a not used Transistor Output 3 See belown/a not used Digital Input 3 See belown/a not used Transistor Output 2 See belowPS GND ground Transistor Output 1 See below24 VAC 24 VAC Digital Input 2 See below24 VAC 24 VAC Digital Input 1 See belowLED Color DescriptionNetwork Green Steady for connection to 100 Mbit/s network. Flashes for network activity.Amber Steady for connection to 10 Mbit/s network. Flashes for network activity.Unlit No connection.Power Green Normal operation.Amber Flashes green/amber during firmware upgrade.