Product Core Brief

• Model: IS220YDIAS1A
• Brand: GE (General Electric)
• Series: Mark VIe Speedtronic — Discrete Contact Input I/O Module
• Core Function: Discrete contact input module for GE Mark VIe gas and steam turbine control systems, processing dry contact and wetted contact signals.
• Product Type: Discrete Contact Input I/O Module
• Key Specs: 28VDC onboard power supply | 32VDC max contact input rating | -35°C to +65°C operating range | UL & CE listed | Compatible with IS200/IS400 terminal boards
• Condition: New Original / New Surplus

Product Introduction

The GE IS220YDIAS1A is a discrete contact input I/O module from GE’s Mark VIe Speedtronic turbine control series. Designed for both gas and steam turbine industrial control applications, it processes discrete contact signals — including dry contacts and wetted contacts — and routes them to the Mark VIe controller for real-time monitoring and control logic execution.

This module features an onboard 28VDC power supply and supports a maximum voltage rating of 32VDC for both contact inputs and contact wetting outputs. It is designed to plug into and operate with specific terminal boards including the IS200STSIC1A, IS200STSIC2A, IS400STSIC1A, IS400STSIC2A, and IS400TBSC2. The module is both UL listed and CE marked, and is rated for use in both hazardous and non-hazardous locations per the GEH-6725 manual specifications.

Key Technical Specifications

Quality Control Process

Every IS220YDIAS1A module goes through a four-stage bench check before shipping. First, a visual inspection under magnification checks for cold solder joints, cracked traces, and connector pin damage — common failure points on turbine-deck I/O modules. Second, we power up the module on a verified Mark VIe test rack and confirm the onboard 28VDC supply reads within spec using a Fluke 87V. Third, we inject known discrete contact signals at the terminal board interface and verify the module correctly registers each input state on the IONet bus. Fourth, we verify the contact wetting output voltage stays within the 32VDC max rating under load. Finally, the module is sealed in anti-static foam with desiccant — no exceptions.

Replacement Pitfall Guide

❗ Terminal board compatibility mismatch. The IS220YDIAS1A is designed to work with specific STSIC and TBSC terminal boards. Dropping this module onto an incompatible terminal board will result in no communication or incorrect signal mapping. Always verify the terminal board part number before installation.

❗ Hazardous location rating confusion. This module is rated for hazardous locations, but the specific rating class and division must be confirmed against your site’s area classification per GEH-6725. Installing a module with an insufficient hazardous location rating in a classified area is a code violation.

❗ Contact wetting voltage exceeding 32VDC. The wetting output is rated for 32VDC max. If your field wiring applies a higher voltage to the wetting circuit, you risk damaging the module’s output drivers. Verify your external wetting supply voltage before connecting.

❗ Mark VIe vs. Mark V confusion. The IS220YDIAS1A is a Mark VIe module. It is not backward-compatible with Mark V racks — different backplane connectors, different firmware, different I/O mapping. Verify your system series before ordering.

Keep these in mind and you’ll cut 90% of rework time.

Compatibility Matrix & Benchmarks

Benchmarks:

• Onboard power supply: 28VDC nominal, 32VDC max contact input/wetting output
• Operating temperature: -35°C to +65°C, UL & CE listed for hazardous locations

Need me to pull up the compatible IS200STSIC / IS400STSIC terminal board part numbers and their wiring diagrams? The terminal board pairing is critical for correct contact input mapping.