Instruction manual

Maintenance and Test Procedures
Access Control Design Guide 43
LEDs on the AC24/4 Alarms Controller
LED1 (OK) – When the controller is functioning correctly, this should flash at two-second intervals (one
second on and one second off).
LED2 (DATA Tx) – Illuminated when transmitting data to a database unit.
LED3 (DATA Rx) – Illuminated when receiving data from a database unit.
LED4 (POWER) – Lit steadily while power is applied.
LEDs on the DBU
LED1/3 (COMA/B RX) – Flashes when there is a database unit connected to the COM A/B port. Otherwise,
the LED is permanently illuminated.
LED2/4 (COMA/B TX) – Flashes when there is a database unit connected to the COM A/B port. Otherwise,
the LED is not illuminated.
LED5 (COM C RX) – Flashes when the on-board RS232 port (TB4) is receiving data. Otherwise, the LED
is not illuminated.
LED6 (COM C TX) – Flashes when the on-board RS232 port (TB4) is transmitting data. Otherwise, the
LED is not illuminated.
LED7/9 (COM D/E RX) – Illuminated when receiving data from the plug-in COM D/E port (NIC1/NIC2).
LED8/10 (COM D/E TX) – Illuminated when transmitting data to the plug-in COM D/E port (NIC1/NIC2).
LED11 (DC RX) – Illuminated when receiving data from an external door or alarms controller.
LED12 (DC TX) – Illuminated when transmitting data to an external door or alarms controller.
LED13/14/17 (COM D/COM E/COM C) – Indicates the Port Usage configuration setting for COM ports C,
D and E (as described in the DBU Installation Instructions). 1 flash = Normal Comms (indicates primary
port when two NIC4s fitted); 2 flashes = Bidirectional Comms; 3 flashes = Fall-Back Comms; 4 flashes =
Serial Device; 5 flashes = port off (another port has been set to the same setting); 6 flashes = Secondary
port when two NIC4s fitted.
LED 15 (COM B) – Flashes to indicate COM B (HOST COMMS B) port usage. 2 flashes = port in use; 5
flashes = port not used (RS232, NIC1 or NIC2 port set to Bidirectional Comms port usage).
LED 16 (COM A) – Flashes to indicate COM A (HOST COMMS A) port usage. 1 flash = port in use; 5
flashes = port not used (RS232, NIC1 or NIC2 port set to Normal Comms port usage).
LED18 (DC COMMS) – Illuminated when an external door or alarms controller is connected.
LED19 (OK) – When the DBU is functioning correctly, this should flash once per second.
LED20 (12V) – Illuminated when the 12Vdc supply is connected.
LED21 (5V) – Illuminated when the on-board 5Vdc supply is operating.
LED22 (3V) – Illuminated when the on-board 3Vdc supply is operating.