OMRON C-series/CVM1/CV series analog I/O units

Core positioning

Applicable PLCs: C500/C1000H/C2000H, CVM1, CV500/CV1000/CV2000

Coverage Module: Analog Input (AD)+Analog Output (DA) Full Series

Core applications: Sensor signal acquisition, analog control, temperature/pressure/flow closed-loop

Communication method: IR/CIO area direct mapping+READ/WRIT dedicated instructions

Resolution: Mainstream 12 bit (1/4095), some economy models 10 bit (1/1023)

Module overview (9 series)

1) Analog input unit AD

3G2A5-AD001~005: 2 points, 12 bits, fixed range (1~5V/0~10V/± 10V, etc.)

3G2A5-AD006~007: 4 points, 10 positions, low cost

C500-AD101: 8-point, 12 bit, independent range for each point, mean/peak/break detection

C500-AD501: 16 o’clock, 12 bit, differential input, scaling/filtering/alarm/EEPROM

2) Analog output unit DA

3G2A5-DA001~005: 2 points, 12 bits, fixed range

C500-DA101: 4-point, 12 bit, voltage/current optional

C500-DA103: 4-point, ± 10V bipolar

C500-DA501: 8-point, 12 bit, independent range for each point, ramp/limiter/EEPROM

Core Technical Parameters (General)

Resolution: Mainly 12 bits (4095), AD006/007 is 10 bits (1023)

Input range: 0~5V/0~10V/± 5V/± 10V/0~20mA/4~20mA

Output range: 0~10V/± 10V/0~20mA/4~20mA

Conversion time: 2.5~25ms/point

Isolation: Input – CPU photoelectric isolation; No isolation between channels

Power supply: 5VDC backplane, some models require external 24V

Installation: PLC backplane, cannot be installed on SYSMAC BUS slave station (except for some models)

Most important: working mode (2/4 word mode)

1) Two word mode (high-speed)

Batch read and write using READ/WRIT instructions

Fast speed, occupying less IR area

Only supports: CPU rack, expansion rack, SYSMAC BUS/2 slave station

2) Four character mode (compatible)

Use MOV command to access point by point

The strongest compatibility

Support: All racks (including SYSMAC BUS slave)

Rule: AD101/DA101/DA501 must switch modes with a switch

Core functions (exclusive to advanced models)

AD101/AD501/DA501 support

Free range setting: independent voltage/current at each point

Scaling engineering quantity conversion: directly output engineering units

Mean filtering: Suppressing noise

Peak holding: Capture maximum value

Wire breakage detection: 4-20mA wire breakage alarm

Upper and lower limit alarm: Over range output flag

EEPROM storage parameters: power down save

Wiring and DIP settings (most commonly used)

1) General wiring rules

Voltage input:+connected to signal+, – connected to signal ground

Current input: V – and I must be short circuited-

Shielded wire: single ended grounded, away from power lines

Unused channel: positive and negative short circuits, anti-interference error message

2) DIP switch function

Set range: 0~10V/± 10V/4~20mA

Switch between two character/four character mode

Set power down output to hold/reset to zero

IR/CIO bit allocation (core)

Each module occupies 2/4 IR words

Bit0~11: AD conversion data/DA output data

Bit15: Bipolar symbol bit (1=negative)

Status bits: busy signal, completion flag, alarm, disconnection

Programming instructions (must be mastered)

Read (88): Read AD data/Write DA parameters

WRIT (87): Writing DA output/configuring AD

MOV: Simple Four Word Mode Transfer

BCD, BIN: Data format conversion

Example: AD value → BCD quantity → display/control

Typical application process

Power off → Set DIP range and mode

Wiring (voltage/current)

Power on → Confirm that the RUN light is on

Read AD raw values with READ

Perform filtering/calibration/engineering quantity conversion

Write DA output control valve/frequency converter using WRIT

Troubleshooting (most common)

No input: Range DIP set incorrectly, current not short circuited, wire disconnected

Reading drift: poor grounding, unused channels not short circuited

Output not moving: Two word/four word mode mismatch, instruction not executed

Alarm light on: Over range, external power supply missing, parameter error