Omron ZEN Operation Manual page 27

Outline
Future System Expandability
Power Failure Countermeasures
Easy Saving and Copying of Programs
Refer to page 38.
I/O capacity can be expanded to up to 24 inputs and 20 outputs by
connecting 3 Expansion I/O Units.
Refer to page 9 and 37.
Expansion I/O Units (up to 3)
CPU Unit
I 6 I 7 I 8 I 9 I a I b
20C1AR-A-V2
Q4 Q5 Q6 Q7
12 inputs/8 outputs + (4 inputs/4 outputs) × 3
EEPROM backs up the program and system settings data when no
power is supplied to the ZEN.
Use a Battery Unit (optional) to back up work bits, holding timers,
counters, and date/time data.
Refer to page 110.
Battery
Unit
Use an optional Memory Cassette to easily save and copy programs.
Refer to page 111.
Ladder program
data/settings.
Memory Cassette
Section 1-1
3