GE IC670ALG320 FIELD CONTROL MODULE

»Product Info«

Product description: The Analog Output Module (IC670ALG320) offers four current/voltage analog outputs. Each 

channel delivers a standard range of 4–20mA and 0–10V, with ranges adjustable to 0–20mA and 0–12.5V via a 

jumper on the I/O Terminal Block. Its default scaling is 0 to 20,000, and this scaling can be reconfigured to align 

with the specific output in use or converted to engineering units.

Product origin: United States

Quantity: 100% New Original

»Operation«

Four D/A converters enable each output channel to deliver simultaneous current and voltage outputs. Current 

output ranges are 0–20 mA or 4–20 mA, while voltage ranges are 0–10 V or 0–12.5 V. All outputs are isolated 

from ground and logic, and share a common power supply; however, if a separate isolated loop supply is used, 

the outputs can be isolated as a group from the rest of the system.

Each circuit supports simultaneous voltage and current outputs from its respective D/A converter, with all 

circuits sharing a common loop supply and return path. The current driver is of the sourcing type. The low side of 

a load may be connected to the RET terminal, the negative side of a 24 V loop supply, or a more negative point—

with a maximum negative voltage of 36 V relative to the positive terminal of the module’s 24 V supply. Voltage 

output is referenced to the RET terminal, which is common across all circuits. The module includes a 10 Ω 

resistor to help minimize ground loop circulating currents.

To adjust an output’s operating range to 0–20 mA or 0–12.5 V, connect the JMP terminal to the corresponding 

RET terminal for that output— as illustrated above and on the untagged page of this datasheet. The module is 

equipped with MOV (Metal Oxide Varistor) transient voltage suppressors and RF bypass capacitors connected to 

the module chassis. This chassis connection point links to both the module case and the chassis ground 

terminal on the module base; grounding this point ensures optimal noise immunity. Upon initial power-up or loss 

of backplane power, the outputs default to their minimum values.

»CAUTION«

Ordinarily, no additional wiring to the RET bus is required. However, if a low-impedance ground is needed for all 

devices, the correct approach is to jumper any RET terminal to the power B terminal on the module and ground 

the Loop supply externally.

If the module is mounted on an I/O Terminal Block (equipped with Box Terminals or Barrier Terminals), an 

Auxiliary Terminal Block can be used to provide additional wiring terminals. For I/O Terminal Blocks with Wire-to-

Board Connectors, external connection points are typically preferred—though an Auxiliary Terminal Block is also 

usable.

All terminals of an Auxiliary Terminal Block are internally connected. The Auxiliary Terminal Block with Box 

Terminals has 13 terminals: each can accommodate one wire ranging from AWG #14 (average 2.1 mm² cross-

section) to AWG #22 (average 0.36 mm² cross-section), or two wires up to AWG #18 (average 0.86 mm² cross-

section). The Auxiliary Terminal Block with Barrier Terminals features nine terminals; each can hold one or two 

wires up to AWG #14 (average 2.1 mm² cross-section).

The Panel Ground Shield wire, running from the Auxiliary Terminal Block to the panel, should be AWG #14 and no 

longer than 4 inches (10 cm).

»Function«

The IC670ALG320 is an 8-channel analog input (AI) module belonging to GE Fanuc’s VersaMax industrial control product line, specifically designed for reliable acquisition and conditioning of process-critical analog signals in distributed control systems (DCS) or programmable logic controller (PLC) - based automation setups. Its core function is to receive, process, and convert standard industrial analog signals—including 4–20 mA DC current signals, 0–10 V DC voltage signals, and low-level  (mV) signals (often used with temperature sensors like thermocouples or RTDs)—into high-precision digital data, which is then transmitted to a VersaMax controller via the system’s backplane bus for real-time process monitoring, analysis, and control.

To ensure measurement accuracy and robustness in harsh industrial environments (e.g., oil & gas refineries, chemical plants, power generation facilities), the module integrates key signal conditioning features: electromagnetic interference (EMI) filtering to suppress noise from nearby industrial equipment, precision amplification to enhance weak input signals, and galvanic isolation between channels and the backplane—preventing ground loops, voltage transients, or electrical noise from corrupting data or damaging internal components. It also boasts a 16-bit analog-to-digital converter (ADC) for high-resolution measurements, ensuring minimal error in capturing critical process parameters like pressure, temperature, flow, or level.

Additionally, the IC670ALG320 includes built-in diagnostic capabilities, such as detection of open circuits (in sensor wiring), over-range/under-range signals, and module power faults—all of which trigger status alerts to the controller for proactive maintenance, reducing the risk of unplanned downtime. As a modular component, it supports easy installation into VersaMax I/O chassis, enabling scalable expansion of analog input capabilities to match evolving process needs. Overall, it serves as a critical link between field-level sensing devices and the control layer, ensuring accurate, reliable data flow to support efficient, safe industrial operations.