Allen-Bradley 1738-OE2CM12 ArmorPoint I/O Analog Output Module

The Allen-Bradley 1738-OE2CM12, also cataloged as the 1738-OE2CM12 Analog Output Module, serves as the primary 2-channel current output module utilized to execute 0-20 mA and 4-20 mA analog signal generation across ArmorPoint distributed I/O systems. Configured for single-ended current loop actuation, the Allen-Bradley 1738-OE2CM12 provides direct electrical output synthesis through 16-bit conversion resolution over M12-connected field interfaces.

Suffix Breakdown & Model Matrix

The model 1738-OE2CM12 is structured as:

• 1738: ArmorPoint I/O platform identifier

• OE2: 2-channel analog output configuration

• CM12: M12 connectorized sealed module variant
  No additional functional segmentation or option code hierarchy is defined.

Hardware Specifications

Backplane Communication and Analog Loop Generation Behavior

Within the ArmorPoint architecture, the 1738-OE2CM12 performs analog output synthesis through PointBus synchronized backplane data transfer. Digital setpoints are converted into loop current outputs using 16-bit resolution DAC processing per channel. Output refresh timing is aligned with deterministic I/O update cycles, while channel load is governed by shared module power and backplane current allocation (75 mA class system constraint).

Frequently Asked Questions (FAQ)

Q: Does the module support live replacement under load conditions?
A: Yes. RIUP is supported; however, both analog outputs are forced to a zero-current state during module removal and reinitialization of the backplane communication cycle.

Q: Are the two output channels electrically isolated from each other?
A: No. Both channels share a common reference architecture and are not individually isolated.

Q: What happens if output demand exceeds the 20 mA loop range?
A: The output saturates at the configured upper limit (20 mA or scaled range), with no over-range current generation beyond rated DAC limits.

Field Installation Guidelines

M12 connectors must be fully engaged and locked to maintain IP69K sealing integrity under vibration and washdown conditions. Output loop wiring shall maintain controlled impedance routing and separation from high-frequency switching conductors to prevent noise coupling into 4-20 mA loops. Shield termination must be performed at a single-point ground reference to avoid loop current distortion. During installation or module replacement, ensure output loops are placed in a controlled state to prevent unintended process actuation during backplane resynchronization.