HITACHI AGM Series Modules AGM-OD 33016138-3 Analog Output Module

Technical Dossier

Product Details And Specifications

HITACHI AGM Series Technical Notes

The HITACHI AGM Series represents a core component family within Hitachi's HIZAC EH-series distributed control and programmable logic controller architecture. Deployed extensively across global heavy industry — including petrochemical complexes, nuclear power auxiliary systems, steel rolling mills, and offshore refinery platforms — the AGM series provides the analog signal conditioning backbone for process-critical control loops. Its modular backplane architecture allows integration into both standalone PLC racks and multi-drop DCS configurations, making it one of the most widely installed Hitachi I/O families in Asia-Pacific and Middle Eastern industrial facilities built between the 1990s and 2010s.

The Evolution of AGM Series Architecture

The AGM series was introduced as part of Hitachi's second-generation HIZAC EH modular control platform, succeeding the earlier H-series fixed I/O controllers. Early AGM modules operated on a parallel backplane bus with 5V TTL logic levels and required dedicated rack power supplies rated at 5VDC/3A. Mid-generation revisions introduced optically isolated analog front-ends, improving common-mode rejection ratios (CMRR) to >80dB and enabling direct connection to 4–20mA transmitter loops without external signal conditioners.

AGM Series Full Catalog & Functionalities (SKU List)

Analog Output Modules

• AGM-OD 33016138-3: 4-channel 4–20mA analog output, 12-bit resolution, EH-150/300 rack compatible
• AGM-OD 33016138-4: 4-channel analog output, revised isolation, drop-in replacement for -3 suffix
• AGM-OD 33016140-1: 8-channel 4–20mA analog output module, high-density rack format
• AGM-OD 33016140-2: 8-channel analog output, extended temperature range (-10°C to +60°C)

Analog Input Modules

• AGM-ID 33016130-3: 4-channel 4–20mA analog input, 12-bit ADC, optically isolated
• AGM-ID 33016130-4: 4-channel analog input, revised front-end filter, compatible with thermocouple adapters
• AGM-ID 33016132-1: 8-channel analog input, multiplexed ADC architecture, EH-300 rack
• AGM-ID 33016132-2: 8-channel analog input, enhanced EMI shielding variant
• AGM-ID 33016134-1: 4-channel high-speed analog input, 14-bit resolution, for fast-loop PID

Digital Input Modules

• AGM-DI 33016100-3: 16-point 24VDC digital input, sink type, standard rack mount
• AGM-DI 33016100-4: 16-point 24VDC digital input, source type, revised optical isolation
• AGM-DI 33016102-1: 32-point 24VDC digital input, high-density, EH-300 only

Digital Output Modules

• AGM-DO 33016110-3: 16-point 24VDC transistor output, 0.5A per point, sink type
• AGM-DO 33016110-4: 16-point 24VDC transistor output, source type, revised driver IC
• AGM-DO 33016112-1: 32-point 24VDC transistor output, high-density format

Communication & CPU Modules

• AGM-CPU 33016200-2: Central processing unit for EH-150 rack, 256KB program memory
• AGM-NET 33016210-1: H-Link network adapter, peer-to-peer rack communication
• AGM-PSU 33016300-1: 24VDC rack power supply module, 5A rated output

Quality Control for the AGM Series Range

AGM series modules present specific test challenges due to their parallel backplane bus architecture and mixed analog/digital signal paths on a single PCB. DriveKNMS applies the following test protocol to all AGM units prior to shipment:

• Backplane Interface Verification: Each module is seated in a reference EH-150 or EH-300 rack and subjected to full bus communication handshake testing using a Hitachi EH-CPU reference controller.
• Analog Channel Calibration: All analog output channels are verified against a calibrated 4–20mA loop tester. Output linearity is confirmed across 0%, 25%, 50%, 75%, and 100% of span. Deviation tolerance: ±0.1% of full scale.
• Isolation Resistance Test: Channel-to-channel and channel-to-backplane isolation is measured at 500VDC. Minimum acceptable: 10MΩ.
• Thermal Soak: Units are operated at 50°C ambient for 2 hours to screen for latent component failures.
• Visual & Component Inspection: PCB is inspected under 10× magnification for corrosion, cold solder joints, and capacitor bulge.