Description
Key Technical Specifications
- Model Number: IS220PDIAH1B / 336A5026ADP4
- Manufacturer: GE General Electric
- Product Type: Mark VIe I/O Package (Discrete Input)
- Channel Count: 24 Discrete Inputs
- Nominal Input Voltage: 24.0 VDC
- Maximum Input Voltage: 28.6 VDC (Module), 32 VDC (Contacts)
- Operating Temperature: -30°C to +65°C
- Environmental Humidity: 20% to 80% (Non-condensing)
- Certifications: UL Approved (Hazardous and Non-Hazardous Locations)
- Compatible Terminal Boards: IS200STCIH1A/2A, IS200TBCIH2C/H4C, IS400STCIH1A/2A
- Weight: 0.26 kg
Product Introduction
Turbine control systems demand absolute reliability, and the IS220PDIAH1B delivers exactly that for Mark VIe installations. This discrete input module acts as the critical sensing interface, translating 24 separate field status signals into digital data the turbine controller can process. Whether you are monitoring valve positions, limit switches, or safety interlocks on a gas or steam turbine, this pack handles the electrical isolation and signal conditioning.
Bottom line — it is a specialized part, and finding it in good condition is getting harder. The GE IS220PDIAH1B is rated for a nominal 24 VDC input but can safely handle up to 28.6 VDC, with contact inputs rated to 32 VDC. It operates across a brutal -30°C to +65°C temperature range, making it suitable for both indoor control rooms and harsh outdoor turbine enclosures. Verify your terminal board part number before ordering, as this I/O pack requires specific mating boards like the IS200STCIH1A or IS200TBCIH2C to function correctly.
QA/QC Transparency SOP
- Intake & Origin Verification: We verify the IS220PDIAH1B and 336A5026ADP4 part numbers against GE’s Mark VIe hardware database. Boards are inspected under 10x magnification for rework, lifted pads, or damaged connectors.
- Live Functional Testing: The module is seated in a verified Mark VIe test chassis. We run a 4-hour burn-in, forcing all 24 discrete channels through on/off cycles to verify signal integrity and isolation.
- Electrical Parameter Tests: We perform a megger test on the isolation barrier between input channels and the backplane. Power supply rails are checked under load using a calibrated Fluke multimeter to ensure the 24 VDC input circuitry is stable.
- Firmware/Config Verification: We read the onboard configuration via the Mark VIe diagnostic interface. The exact firmware revision is logged and backed up before shipping.
- Final QC & Anti-Static Packaging: Only units passing all diagnostics are approved. The GE IS220PDIAH1B is sealed in an anti-static bag with foam corner protectors to prevent backplane pin damage during transit.
Field Engineer Gotchas
- Terminal Board Mismatch: The IS220PDIAH1B is an I/O pack, not a standalone module. It requires a specific terminal board. Solution: Always verify your terminal board part number (e.g., IS200STCIH1A, IS200TBCIH2C). I’ve seen guys order the I/O pack and realize on-site they have the wrong base board, causing a 2-week delay.
- Voltage Rating Confusion: The module has three different voltage specs. Solution: Module nominal is 24 VDC, max is 28.6 VDC, but contact inputs can handle 32 VDC. If your field wiring runs at 28 VDC, you are within spec, but if it spikes to 35 VDC, you will fry the input circuitry. Check your power supply regulation.
- Hazardous Location Compliance: This module is UL listed for hazardous locations, but only when used with the correct terminal boards and in the proper enclosure. Solution: Do not assume the I/O pack alone is intrinsically safe. Verify the entire assembly (pack + terminal board + enclosure) meets your Class/Zone requirements per the Mark VIe documentation.
- ESD Sensitivity: The Mark VIe I/O packs are highly sensitive to electrostatic discharge. Solution: Always ground yourself before handling the . I’ve seen modules fail silently after being handled without proper ESD protection, only to show intermittent faults weeks later.
GE IS220PDIAH1B 336A5026ADP4
Application Scenarios
- Gas Turbine Control: Monitoring 24 discrete status signals (valve positions, flame detectors, safety trips) on Frame 6/7/9 gas turbines using the Mark VIe Speedtronic system.
- Steam Turbine Protection: Providing critical input signals for emergency shutdown systems in steam turbine generators, leveraging the -30°C to +65°C operating range.
- Power Plant Auxiliary Systems: Interfacing with cooling water pumps, lube oil systems, and auxiliary transformers in fossil fuel plants.
- Real-World Failure Case: A combined cycle plant experienced a turbine trip due to a false safety signal. Diagnostics traced the fault to a failed discrete input channel on the . The module had been in service for 12 years and suffered from thermal degradation. Swapping in a tested replacement restored full input monitoring, preventing a $200k/hour outage.
FAQ
No. The is specifically designed for the Mark VIe platform. It will not work in legacy Mark V or Mark VI (non-e) racks. Verify your system generation before ordering.
Can I hot-swap this module?
The Mark VIe system supports hot-swapping in redundant configurations. Practically? I only do it if the turbine cannot be shut down. Hot-swapping on old backplanes with oxidized pins is a great way to cause a transient fault. Power down if you can.
It’s almost always a missing or incorrect terminal board. The I/O pack cannot function without its mating base. Check that you have the correct IS200 or IS400 series terminal board installed and properly seated.
What terminal boards work with this I/O pack?
Compatible boards include IS200STCIH1A, IS200STCIH2A, IS200STCIH8A, IS200TBCIH2C, IS200TBCIH4C, IS400STCIH1A, IS400STCIH2A, IS400STCIH8A, and IS400TBCIH2C. Verify your exact part number against the Mark VIe hardware manual.
Does this module support 125 VDC inputs?
No. The is rated for 24 VDC nominal, 28.6 VDC maximum. If you need 125 VDC discrete inputs, you need a different I/O pack (e.g., IS220PDIAH1C or similar high-voltage variant).
What is the response time for discrete inputs?
The Mark VIe discrete input scan time is typically 10-20ms, depending on system configuration. For safety-critical applications, verify your application-specific scan rate in the Mark VIe configuration tool.
Do you test these before shipping?
Every single one. We don’t sell “as-is” unless clearly marked. You get a test report showing all 24 channels pass/fail, firmware version, and insulation resistance. If it doesn’t boot on our Mark VIe test rack, it doesn’t go in your box.
