Omron CJ1W-MAD42 Analog I O Module: Analog Input and Output Unit for CJ Series PLC

Product Overview

The Omron CJ1W-MAD42 is a Special I/O Unit designed for the SYSMAC CJ series programmable logic controllers, providing four analog input channels and two analog output channels within a single compact module. This analog I O module allows CJ series PLCs to interface with analog field devices such as pressure transmitters, temperature sensors, flow meters, and actuator positioners. The unit is equipped with an 18-point detachable terminal block using M3 screws, simplifying field wiring and maintenance. The CJ1W-MAD42 occupies a single slot in the CJ series rack and is compatible with all CJ series CPU units, making it a versatile solution for adding analog measurement and control capabilities to existing automation systems.

Key Features of Omron CJ1W-MAD42

The analog input section of the CJ1W-MAD42 supports four channels with selectable voltage and current input signal ranges. Voltage input ranges include 1 to 5 V, 0 to 5 V, 0 to 10 V, and -10 to 10 V, while current input is supported with a 4 to 20 mA range. The maximum rated input is ±15 V for voltage and ±30 mA for current, providing a safety margin against accidental overrange conditions. Input impedance is 1 MΩ minimum for voltage inputs and 250 Ω rated for current inputs, ensuring minimal loading on field transmitters. The A/D conversion period is selectable at 1.0 millisecond or 500 microseconds per point, allowing engineers to balance conversion speed against processing load based on application requirements.

The analog output section provides two channels configurable for voltage or current output, supporting the same signal ranges as the input section. The D/A conversion period is specified at 1.0 ms per point, ensuring timely updates of output signals for actuator control applications. The module includes an input disconnection detection feature that flags open-circuit conditions on 4 to 20 mA input channels, preventing erroneous measurements from being used by the PLC program. Scaling functionality is supported when operating with a 1 ms conversion period and 4000 resolution, allowing users to map the raw 0 to 4000 or 0 to 8000 digital values to engineering units within the ±32,000 range.

Technical Specifications

• Manufacturer: Omron Corporation

• Part Number: CJ1W-MAD42

• Unit Type: CJ-series Special I/O Unit

• Analog Inputs: 4 channels

• Analog Outputs: 2 channels

• Input Signal Ranges: 1 to 5 V, 0 to 5 V, 0 to 10 V, -10 to 10 V, 4 to 20 mA

• Output Signal Ranges: Same as input ranges

• Input Impedance: 1 MΩ min (voltage), 250 Ω (current)

• Resolution: 4000 or 8000 selectable

• A/D Conversion Period: 1.0 ms / 500 μs per point selectable

• Accuracy at 25°C: ±0.2% of full scale

• Accuracy 0 to 55°C: ±0.4% of full scale

• Isolation: Photocoupler isolation between I/O and controller signals

• Current Consumption: 580 mA max at 5 V DC

• Dimensions: 31 × 90 × 65 mm (W × H × D)

• Weight: 150 g max

• Terminal Block: 18-point removable, M3 screws

Functional Description

The CJ1W-MAD42 continuously converts analog input signals to 16-bit binary data that is stored in the Special I/O Unit area of the CPU units memory. The CPU can access these values at each scan cycle to use in control calculations, alarm monitoring, or data logging applications. For outputs, the CPU writes desired analog output values to the Special I/O Unit area, and the module converts these digital values to corresponding voltage or current signals. The mean value processing function can be enabled to store the average of the last n conversion values in the buffer, with n selectable from 2, 4, 8, 16, 32, or 64, providing noise reduction for applications with fluctuating signals. Peak value holding captures the maximum conversion value while a control bit is energized, useful for monitoring peak pressures, forces, or flows during process cycles.

Applications

The Omron CJ1W-MAD42 analog I O module is deployed in industrial automation applications requiring measurement and control of continuous process variables. Typical applications include temperature monitoring in heat treat furnaces, pressure control in hydraulic systems, level measurement in tank farms, flow rate control in chemical processing, and position feedback in servo systems. The module is also used in test and measurement systems where analog signals from sensors must be captured and analyzed by the PLC control program. For system integrators retrofitting older equipment, the CJ1W-MAD42 provides a cost-effective solution for adding analog capability to CJ series PLC systems without requiring additional racks or power supplies.