The 1747-L531 SLC Processor contains 8K words total (4K words for data or prog.; 4K words for data only) user memory, max. The number of I/O for 1747L531 is 4096 in + 4096 out absolute maximum. Local analog I/O, max, for the processor is 480. It has a program scan time of 1ms (typ), and I/O scan time of 0.225ms (typ). Number of I/O module slots in the local I/O chassis (max) is 30; number of local I/O chassis (max) is 3. Backup memory is flash, battery-backed RAM is standard. Processor contains a backplane current load of 500mA at 5V DC or 175mA at 24V DC.