用以存放用户程序即存放通过编程器输入的用户程序。PLC的用户存储器通常以字（16位/字）为单位来表示存储容量。同时，由于前面所说的系统程序直接关系到PLC的性能，不能由用户直接存取。因而通常PLC产品资料中所指的存储器型式或存储方式及容量，是对用户程序存储器而言。
常用的用户存储方式及容量型式或存储方式有CM0SRAM，EPR0M和EEPR0M。信息储存常用盒式磁带和磁盘。
CM0SRAM存储器是一种中高密度、低功能、价格便宜的半导体存储器，可用锂电池作为备用电源。一旦交流电源停电，用锂电池来维持供电，可保存RAM内停电前的数据。锂电池寿命一般为1―5年左右。
如果CPU上装着EPROM储存器，把EPROM拔下，装在新的CPU上
(R2-1) 1 ECCI MWB146 CONTROLLER LENGTH / TOTAL / SPEED / SHEET
Emerson 1C31197G02 Valve Positioner Module
IBM 73P7575 FRU 73P7576 Blade Center Alarm Panel Cable,
(Q1-5) 1 CUTLER-HAMMER A50BN0 STARTER REVERSING 18AMP
Furuno IMEE2 Inmarsat-C Mobile Earth Station FELCOM15 Install Manual,
Barber Colman Auxiliary Equipment Module 80QA #7208
Pacific Scientific S21-HNNA-HGNS-02 Brushless Servo Motor, !
Honeywell/North S, Small Size, Half Mask, Air Purifying Facepiece, Un
Bausch & Lomb (B&L) Stereozoom 3, 1 to 2.5X Stereozoom Microscope + 2 Eyepieces
(N3-2) 1 SQUARE D H-221-D SAFETY SWITCH
(4163) Dwyer Smart Indicator Transmitter 13220
SQUARE D 9050A010E PNUEMATIC TIMER
MICROSWITCH DTF2-2RQ9-RH SWITCH
Barber Colman Sequence Hydraulic PC Board A #19679
3Com 3CGBIC91 1000BASE-SX 850nm, Short Wave, GBIC Transceiver
Asea Brown Boveri Circuit Board YB161102 BA/4 #51149
Sanyo Denki Servo Amplifier PZ0A150HSL6S3N #72849
Boeckeler VIA-170KL 6 Mode Video Image Marker Measurement System
Multilink MTC5589, 12.249 Gb/s, SMA (F), Clock & Data Recovery Module
Bimba QF-MRS-041-D, 3/4" Bore, 1" Stroke, Pneumatic Cylinder (!)
Allen Bradley AC Servo Motor 1326AS-B330H-21 #78118
Shibaura - Big Zero Sensor Control Board Type Tls (5033)
(N3-2) 1 SQUARE D H-221-D SAFETY SWITCH
Anaren 2 to 4 GHz, 0° + 3dB, 90° - 3dB, SMA (F) 2 Way, Hybrid Coupler
Nissei Power Supply F3PU20 #69885
Magnetek (Yaskawa) GPD333, 0.75 HP, 3 PH, 0 to 400 Hz, Variable AC Drive, Tested
Panasonic AC Servo Driver DV451S100 #5822
Wollensak Raptar 1/2", F/1.5, C Mount, Wide Angle Camera Lens + Lens Cover
Danfoss Hydraulic Motor OMS 80 #54214
(N2-1) 1 PARKER 1J OIL FACTOR
Parker Hannifin ZETA8, 200 nsec-min, 2 MHz Pulse, Compumotor, Stepper Drive
ANVER T PAD SLIDE ASSEMBLY
Mini-Circuits ZFSC-3-13, 1 to 200 Mhz, 50 Ohm, 1 W, SMA (F) Power Splitter
Matheson Gas Products 3322B, 3000 psig Max, 0.12", Pressure Regulator
Paralan SD10C/01 SE-HVD, SCSI Converter & Extender
SQUARE D QGL32150 CIRCUIT BREAKER
HP / Agilent 909D () DC to 26.5 GHz, 3.5mm (m) Coaxial Termination
Nippon Denso Servo Teach Pendant #10407
Vectron 80.000 MHz, Precision Crystal Oscillator
Intermec Janus D2020 Charging Station
HP E1413C High Speed, 64 Channel, Scanning A/D, VXI Converter
Sanken PC Board DK24193B
Festo Electric Actuated Counter Timer PZVT-999-SEC-B #71488
SIEMENS ED22B050 MOLDED CASE CIRCUIT BREAKER
Reliance Electric Electro - Craft Servo Motor 1326AB-B420H-21 #78113
HP 17255D DB25 Male to Female (7 pin) 4 ft. Printer Cable
Allen Bradley Servo Drive 1398-DDM-009X-DN #68547
