描述
由于系统程序及工作数据与用户无直接联系，所以在PLC产品样本或使用手册中所列存储器的形式及容量是指用户程序存储器。当PLC提供的用户存储器容量不够用，许多PLC还提供有存储器扩展功能。存储器主要有两种：一种是可读/写操作的随机存储器RAM，另一种是只读存储器或可擦除可编程的只读存储器ROM、PROM、EPROM和EEPROM。
RELIANCE ELECTRIC 0-57421-2B NSFP 0574212B
RELIANCE ELECTRIC MOD BUS INTERFACE 0-57414-1L *NEW*
Reliance Electric Thyristor Rectifier Stack: 86466-59S
Reliance Electric ES281CMB 275W Power Lorain Products
**NIB** Reliance Electric Regulator Card 413338-1YA
Expedited shipping available
RELIANCE MODEL B/MO-55326 DRIVE BOARD 22-475-0827R NEW
**FS** Reliance Electric Analog Input 61C542A
Expedited shipping available
**NIB** Reliance Electric O-55325-55 0-55325-55
Expedited shipping available
Reliance Electric HR2000 BLA-16 AC Servo Drive w/cables
RELIANCE 0-51893-4 FCCE FIELD EXCITER**RFB BY RELIANCE*
