IC695ALG728 PACSystems RX3i HART Analog Module | GE Fanuc

Technical Specification Matrix

The IC695ALG728 is a high-performance, non-isolated 8-channel analog output module designed for the PACSystems RX3i platform. This advanced module, manufactured by Emerson Automation (formerly GE Intelligent Platforms), features integrated HART (Highway Addressable Remote Transducer) version 5.0 capabilities across its output channels, driven by two dedicated onboard HART modems.

Global PLC Spare HUB's Insight

The IC695ALG728 is a premier choice for plants requiring tight closed-loop control alongside deep asset management. In the process industries, configuring smart field devices directly from the control room is a massive operational cost-saver. Because this module features two integrated HART modems (routing four channels per modem), it passes digital configuration and diagnostic commands directly over the standard 4-20mA current loop without interrupting the analog control variables.

However, when integrating this module into your PACSystems rack, pay close attention to backplane power budgeting and update rates. When HART is enabled, the overall analog update rate drops from 8 milliseconds to 16 milliseconds across all eight channels due to the digital packet modulations. If your loop requires sub-10ms response times (such as rapid-acting turbine bypass valves), you may need to disable HART scanning on those critical channels to maintain the native 8ms update speed.

Target Applications & System Integration

The IC695ALG728 is highly suited for process loops utilizing smart field actuators:

• Control Valve Positioners: Modulating smart positioners (e.g., Fisher FIELDVUE) while querying internal diagnostics, stem travel feedback, and device calibration states.
• Variable Frequency Drives (VFDs): Delivering precise speed reference signals while monitoring motor parameters via HART.
• Dosing & Metering Pumps: Controlling chemical feed rates with exact current regulation down to 15.6 bits of resolution.
• Combustion Air Dampers: Providing bipolar voltage inputs (-10V to +10V) for fast-acting electronic actuators.

Advanced Diagnostic Capabilities

The IC695ALG728 features extensive on-board diagnostic mechanisms that are reported directly to the RX3i CPU fault tables:

• Open Loop Detection: Instantly flags a broken wire or open circuit when running in 4-20mA mode, preventing the controller from driving a dead channel.
• Output Voltage Protection: Features short-circuit protection and withstands external back-voltages up to -30V for 60 seconds and +30V for one hour in current mode.
• Alarm Limits and Clamping: Low and High alarms, plus under-range and over-range clamping limits, can be set per channel in Machine Edition to prevent out-of-bounds process variables.

Logistics, Global Shipping & Warranty Terms

• 12-Month Hardware Warranty: Global PLC Spare HUB covers this module with a full 12-month replacement warranty against component failure.
• Rapid Dispatch Process: All units undergo strict testing and are packed securely in anti-static ESD shielding prior to departure.
• Global Express Courier Support: We expedite all shipments using premier priority carriers: **FedEx**, **UPS**, and **DHL** to guarantee minimal system downtime.

Professional Technical FAQ & Purchasing Guide

Q1: Why is my IC695ALG728 analog module failing to power up when the RX3i rack power supply is fully active?

Unlike standard low-power I/O, the IC695ALG728 cannot run solely on backplane power. It requires an external user-provided power supply connected to the terminal block, rated for 19.2 to 30.0 VDC (24V nominal) capable of supplying at least 250 mA. Without this external 24V loop power, the analog circuitry remains inactive and a module fault will be generated in the CPU controller log.

Q2: How do the two integrated HART modems distribute channel communications, and how does this affect polling times?

The module routes channels 1 to 4 through the first HART modem, and channels 5 to 8 through the second modem. Because the channels share a modem in groups of four, digital communication is polled sequentially. If you have active HART devices on all eight channels, it will take approximately 2 seconds to refresh all digital parameters across the network. If speed is critical, limit HART configuration to fewer channels.

Q3: Can I configure channels on the same module with a mix of current outputs and voltage outputs?

Yes. Every channel on the IC695ALG728 is individually software-configurable. You can configure Channel 1 for 4-20mA current control, Channel 2 for -10 to +10V bipolar voltage control, and Channel 3 for 0-10V unipolar control without any jumpers. All configuration is done via PACSystems Machine Edition hardware configuration settings.

Q4: How does the lack of channel-to-channel isolation affect my field wiring design?

The IC695ALG728 features optical isolation between the field-side terminals and the PLC backplane (rated at 2550 VDC for 1 second), but the eight output channels are non-isolated from one another. They share a common ground. If your field actuators run on different ground reference points, you must use external analog signal isolators to prevent ground loop currents from distorting the analog outputs.

Q5: When buying this card for an existing GE Fanuc rack, are there compatibility differences between GE-labeled and Emerson-labeled cards?

No, they are fully form, fit, and functional equivalents. Emerson acquired the GE Intelligent Platforms division and rebranded the PACSystems RX3i line. The catalog number IC695ALG728 remains identical. When purchasing, check the hardware revision letter (suffix) and firmware version; later versions offer improved noise immunity and smoother integration with PACSystems Machine Edition version 9.5 or newer.

Tags