Omron C1000H-CPU01-V1 Programmable Logic Controller CPU

The Omron C1000H-CPU01-V1 is a CPU module belonging to the C1000H series of programmable logic controllers. These PLCs were widely used in industrial automation from the 1980s through the early 2000s. The C1000H is a modular rack‑based system supporting a variety of I/O, analog, and specialty modules. The CPU01-V1 model is the central processor that executes the user’s ladder logic program and communicates with I/O modules via the backplane bus. Although considered legacy, the C1000H remains in service in many facilities, and this CPU is a critical spare part for maintaining those systems.

Technical Specifications

• Model: C1000H-CPU01-V1

• Program Memory: 32K words (RAM with battery backup)

• Data Memory: 2048 words (DM area), 4096 words (EM area on some revisions)

• I/O Points: Maximum 2048 (with expansion racks)

• Scan Time: 0.4 µs per basic instruction (typical)

• Built‑in I/O: None (requires separate I/O modules)

• Programming Port: RS-232C (6‑pin mini‑DIN) and peripheral port

• Battery: 3V lithium (3G2A9-BAT08) for program and data retention

• Power Supply: 5V DC from backplane (2A max)

• Operating Temperature: 0–55°C

• Dimensions: 250mm x 100mm x 130mm

• Weight: 1.2 kg

Functional Architecture

The C1000H CPU scans inputs, executes user program, updates outputs in a cyclical fashion. It supports ladder diagram programming with basic (LD, OUT, AND, OR, TIM, CNT) and advanced (MOV, CMP, ADD, SUB, etc.) instructions. The CPU also features an interrupt function, high‑speed counters (with dedicated input modules), and a real‑time clock (with optional module).

Memory Organization

The user program memory (32K steps) is CMOS RAM with battery backup. The data memory includes: CIO (I/O) area (2048 bits), work area (2048 bits), holding area (1024 bits), timer/counter area (512 each), data memory (DM) area (2048 words), and extended data memory (EM) area (4096 words on V1 variant). The CPU also has a built‑in ROM that holds the system software (operating system).

Communication and Programming

The CPU has two ports: a 6‑pin RS-232C port (TTL level) for connection to a host computer or HMI, and a peripheral port (Omron proprietary) for programming via the C500‑LK009‑V1 programming console or a PC with a CQM1‑CIF02 cable. Programming software used originally was SYSMAC Support Software (SSS) running on MS‑DOS, or later CX‑Programmer (limited compatibility).

Expansion Capability

The CPU mounts in the main rack (C1000H-BCxxx) and can control up to 3 expansion racks (using I/O connecting cables). Each rack can hold up to 8 I/O modules. Maximum I/O points: 2048 digital points. Analog modules (C1000H-AD001, DA001), temperature modules, and high‑speed counter modules are also supported.

Diagnostics and LED Indicators

Front panel LEDs: POWER (green), RUN (green), ERR (red), ALARM (yellow). An optional battery error LED indicates low battery. The CPU stores error codes that can be read via the programming device. Common errors include program checksum error, I/O bus error, or system watchdog timer expiration.

Battery Replacement and Data Backup

The CPU uses a CR2032 or Omron 3G2A9-BAT08 battery. To replace without losing program, the CPU must be powered on. The battery life is approximately 5 years. The program can be backed up to a PROM or EPROM chip (optional memory cassette). Without a battery, the program is lost after 10 minutes of power off.

Environmental and Compliance

Operating temperature: 0–55°C; humidity 35–85% non‑condensing. The CPU is UL 508 and CSA certified. It is not RoHS compliant (older lead‑based solder).

Typical Applications

The C1000H PLC was used in packaging lines, assembly machines, material handling, and process control in industries like automotive, plastics, and food processing. The CPU01-V1 is often sought as a replacement part for legacy systems still in operation.

Installation and Compatibility

The CPU inserts into the main rack’s leftmost slot. It is compatible with all C1000H I/O modules and most C500 I/O modules (with adapter). When replacing a failed CPU, the user program must be reloaded from backup or reprogrammed. Some newer C200H series modules are not compatible.

Conclusion

The Omron C1000H-CPU01-V1 CPU module remains a vital component for maintaining legacy automation systems, offering proven reliability and a straightforward ladder logic architecture.