Series 90-30 PLC Mode|311/313 5 or 10 slots Intelligent Back Plane Cost Effective Small Footprint CPU All slots Available for I/o Fastest in its class Intelligent Back Plane Style System CPU311 CPU313-5 Slots CPU321. CPU323-10 Slots Series9030-022894Series 90-30 - 02/28/94 p4 Series 90TM -30 PLC • 5 or 10 slots • Intelligent Back Plane • Cost Effective • Small Footprint • All slots Available for I/O • Fastest in its class Model 311/313 System CPU Intelligent Back Plane Style - CPU311, CPU313 - 5 Slots - CPU321, CPU323 - 10 Slots