Key facts
- Brand
- Omron
- Model
- CPU21
- Category
- Industrial Supply
- Documents
- 2
- Languages
- EN
- Last added
- 2012-05-07
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Omron CJ1M-CPU21/22/23 CPU Units Operation Manual
This manual introduces the CJ‑series built‑in I/O CPU units, outlines safety symbols such as Danger, Warning and Caution, and explains the concept of unit versions used to manage functionality across CS/CJ series CPUs. It also lists the unit version labeling system and how versions are indicated on nameplates.
The document describes how to confirm a unit’s version using CX‑Programmer (v4.0 or later) via the PLC Information dialog or the Unit Manufacturing Information screen. It includes technical data such as PLC type, program memory size, data memory, and timer/counter capacity, helping users configure and maintain the CJ1M CPU units effectively.
Omron CPU21 specifications
| PLC type | CJM CPUZ3 |
|---|---|
| Unit version | 20 |
| Program memory | 21504 Steps |
| Usable program steps | 20686 Steps |
| Data memory | 32768 Words |
| Timer/counters | 8 KWwords |
All Omron CPU21 documents by type
Day-to-day operation, settings and troubleshooting. Start here if the product is already set up.
Questions answered in these manuals
How can the unit version of a CJ1M CPU be confirmed?
Use CX‑Programmer version 4.0 and view the PLC Information or Unit Manufacturing Information dialog to see the unit version number.
What does a Pre‑Ver. 0.0 CPU unit indicate?
It indicates a CPU unit for which no unit version is given on the nameplate.
