Chapter 6 Applied Instructions 6-149 Interrupt number Description Priority order I33 Communication interrupt (COM2) 34 I34 24 V low voltage interrupt Whether the external 24 V voltage is normal can be checked by the terminals VS+ and VS- on AH500PS05-5A. If the external 24 V voltage is abnormal, users can execute the corresponding program by means of the interrupt subroutine I34. 35 I35~I39 Reserved 36~40 I40~I251 External interrupt 41~252 I252 Timed interrupt 0 Default value: 100 ms (1~1000 ms) 253 I253 Timed interrupt 1 Default value: 40 ms (1~1000 ms) 254 I254 Timed interrupt 2 Default value: 20 ms (1~1000 ms) 255 I255 Timed interrupt 3 Default value: 10 ms(1~1000 ms) 256